Solid Model Memories.net

This will be a longer post over a period time.
Drawings and wood Orta Saint - Hubert G - 1
The Orta Saint - Hubert G - 1 is a small monoplane from the 1930's. The plan, with the story, came from my son-in-law  It is a Belgian design and was flown as a sport plane. This particular model interested me as it turns out, my son-in-law's grandfather ( and thus my grandsons great-grandfather!) owned and flew it during the 1930's and had some noteworthy adventures with it.

This address will bring up lots of photos of the aircraft type and variations.

https://www.google.com/search?q=orta+saint+hubert+g1&client=safari&rls=en&source=lnms&tbm=isch&sa=X&ved=2ahUKEwjX9dyY_KH4AhUkGTQIHRKKB1MQ_AUoA3oECAEQBQ&biw=823&bih=1033&dpr=1

The airplane is a parasol wing, three seat, open cockpit style with a five cylinder radial engine. Given the period the airplane came from, it looks remarkably modern in design. The engine case is nicely streamlined with a cowl. The fuselage and empennage (tail section) are of a modern shape. The landing gear, however, is designed with large vertical struts attached to the wings and axels, that usually result in a weak point.
When comparing the 3-view plan with several pictures of the actual aircraft, it was apparent that the plans are an earlier model. The plane has a clipped rudder and fin and is missing a headrest for the aft cockpit. Using the pictures as a guide I drew in the appropriate curve for the fin and rudder top along with a head rest. Also cockpit openings were added to the top view.

There is no centre line on the fuselage top view, so I marked one out on the plan using the centre of the propeller shaft and training edge of the rudder.

Preparing the plans picture: 3 view master jpeg

I used my computer with the program INKSCAPE, which is an open sourced (free} download from https://inkscape.org , to scale and draw in the missing components. There is a bit of a learning curve on the software. Another method to scale you plan using the computer is to print the jpeg of the plan and set the reduction in print size to fit the scale you want.

Speaking of scale, there is a great app I use called "Model Scaler". You enter the dimension of the prototype (real world size), enter the scale desired 1:48 for this model and the model dimension is given as a calculation Use whatever measuring system or even mix them to get the results you want to work with. Of course you can always calculate the size manually.

I use 1:48 for small aircraft such as this as I find it is a bit easier for me to get the details I want yet does not require much material. I primarily use the wing span as the main measurement to set the scale size. It seems that dimensions given can vary for the fuselage and height due to ambiguous reference points, but the wing span measurements generally are accurate tip-to-tip.

This aircraft span is 9.98 meters. 9.98/48 = .208 m = 8.189 inches. If the plan is shrunk to provide a wing span of one of those dimensions ( metric or imperial, pick one but remain consistent) the remainder of the components will set to the proper scale as well. In some drawings the fuselage length is different from the side compared to the top. Take an actual measurement from the drawing side view and compare the same points on the top view. They should be the same, but small variances can be tolerated.
I also draw a one inch square on the drawing before it is printed. this will ensure that what I had drawn on the computer, prints out to the right size on the paper.

Once you ware satisfied with the drawing, you will need to print several copies. During the construction, you will need to cut out the desired view to use in cutting out the wood blanks.

Wood block selection

WARNING: UNDERSTAND ALL SAFETY PRECAUTIONS, USE SAFE TECHNIQUES AND PROCEDURES FOR THE PARTICULAR TOOLS IN USE AND ENSURE THEY ARE APPROPRIATE FOR THE TASK.

The model will require at least two blocks of wood; Fuselage and wing. The tail components can be cut from scraps of thin would as desired.

I tend to use three types of wood for my models. Spruce, bass wood and maple.
The spruce is from construction 2x4 where I look for the straightest and finest grain in the wood. You only need small lengths so even if there are large knots in the board, it may be possible to find the choice wood in the clear sections. The entire model can be made with spruce, which carves and sands nicely

Bass wood is a bit more exotic out here on the West coast of Canada and it is shipped from the eastern part of the country. It is more expensive, but generally the wood is of high quality, dry, straight and clear of knots. It works very well with all tools and can be used for the entire model if desired.

Maple is a very hard wood that is not too expensive here and the pieces available are usually of nice quality. Its strength and hardness make it difficult to work with hand tools. Powered machine tools work well. It can be used to make small parts that need to hold detail or are thin and need the strength. I use maple for tail surfaces as they are usually quite thin, small propeller blades, struts etc. It can be sanded to razor thin if needed and still be strong enough.

Of course, most any wood can be used, mahogany, balsa, yellow cedar  even plywood for some parts. Usually what ever is available in your area can be used.

Block preparation

(IMG_9779.JPG)
All of the blocks I found for this model were cut off from previous projects. Hand saw, band saw, scroll saw or table saw can be used to make the rough blocks

Construction 2x4 are actually 1-1/2 x 3-1/2 inches in section.  The fuselage needs a minimum height of 1" and a width of just over 5/8" and 5" long. Cut a piece 10" long from the section of 2x4 free of knots and cracks. To make things simple, cut (rip) the length down the middle so you have two pieces 1-1/2 x 1-1/2 square  x 10 inches long. Top and bottom should be parallel to each other and square to the sides which are parallel.

Looking at the end of the square block, note the direction of the wood end grain. Up and down (I) called vertical grain, diagonal across (/) is quarter sawn  or flat sawn left to right (-). Vertical grain is preferred as it gives pretty much the same grain pattern on the sides as the top/bottom. If you have vertical grain, orient the block so the end grain runs up and down.

My fuselage block is 1-1/4 x1-1/4 x9 inches. Setting over the fuselage outlines, it covers them completely indicating that the model will fit.(IMG_9771.JPG)

The wing block is basswood as I had a small piece that was the right size, 3/4 x 3-3/4 x 8-1/2 long. there are a couple small knots that are located on the face, but will be cut away. The working blank will be 5/16 x 2 x 8-1/2 and so must be cut from the block. i marked a line the length of the block 2" from the edge to exclude the two little knots.
(IMG_9788.JPG)

I then marked a line 5/16" from the top of the wing block which will also be the top of the finished wing. Saw the thin piece from the block keeping the thickness at least 5/16 for the whole cut. Grain direction for this block is probably going to be flat grain, but this is fine.

The maple scraps are 1/4 thick and cover the stabilizer and rudder so they will be used as is .

Marking and applying paper templates to the fuselage blocks

I generally cut the fuselage blank first, then the wing and then the tail surfaces. In this model, it is easier to cut out the wing and tail first as they make good practice using the tools.

It is important for the fuselage block to be square and parallel as this will make cutting out the profiles easier and more accurate.
Coping saw, band saw, scroll saw can all be used here.

(IMG_9768.JPG)
Mark the centre line along the top surface.  I used a small marking gauge or use a pencil (HB) and a straight edge to make sure the line is straight and parallel to the sides. Slightly off centre either way is not too critical at this point.
Now mark a line on the side parallel to the top. You will notice a line running fore and aft along the fuselage of their model. This is a feature on the aircraft that can be used as a longitudinal reference to align the pattern on the block. Position it not too high or too low. On some drawings there is a theoretical line depicted that is used as a reference for the aircraft and should be used for aligning the pattern. It may be significantly above or below the centre of the block.

Now take a paper drawing and cut out the top view of the fuselage. Contain the outline  centred within a rectangular box the width and length of the block. Set the pattern on top of the block aligning the centre lines. It should sit neatly on the top of the block. This is a dry run and if it all fits well it can then be secured to the block.

The pattern can be secured with a thin layer of wood glue, rubber cement, double sided tape, spray photo mounting adhesive or what have you along those lines.
Apply the glue and be sure the centre lines line up then press the template on top of the fuselage.

Let the glue dry for a few minutes. If the template overhangs the sides of the block, trim them away using a sharp knife. Leaving the edges overhanging the block will cause problems when working on the sides.

(IMG_9782.JPG)
Look at the top of the pattern and note where the leading edge of the wing crosses the fuselage centreline . The leading edge also appears to coincide with the aft edge of the cowl as viewed on the side view. This will be a reference point. Take a sharp awl or similar tool to make a counterpoint mark at the intersection of the leading edge and centre line.

IMG_9783.JPG
Now on the side of the wood block, mark a line straight down to indicate where this point is on the side. It should intersect the side reference line and this will locate the side template  fore and aft at the cowl line

Do the same procedure to mark references using the leading edge of the horizontal stabilizer at the intersection with the centreline and mark a line down to provide a reference point at the tail.

Now cut the template from the plan side view and use the reference line to align the template level. Use the cowl line and stabilizer lines to locate the template fore and aft. If all is good, glue and trim the template as before.

Drilling alignment pin holes on fuselage block

(IMG_9791.JPG) (IMG_9794.JPG)

For this operation a drill press is the best tool. It can be done with hand drills or a Dremel but precision on holding the drill square and vertical s important.

Using a 1/16" twist drill, drill a vertical hole on the top view at the centreline / wing leading edge intersection and also at the stabilizer/ centreline intersection through the block. Roll the block over and drill the holes at the cowl / reference line intersection and the stabilizer leading edge /reference line intersection.

These holes will now allow you to find and redraw the centre line and reference lines as needed when carving. They will also be used to align the wing and tail surfaces during assembly, hold the model when needed and locate features on the model for adding details.

Rough cut the top view of the fuselage (plan view)

You may notice the headrest fairing is above the top of the block. No worry as this will be made from a separate piece.

(IMG_9797.JPG) (IMG_9798.JPG)(IMG_9799.JPG)
I used a band saw to cut the fuselage block to rough shape. Make sure your bandsaw blade is square to the table before starting

Cut the side view of the fuselage out making sure the blade is on the waste side of the lines. Try to plan your cuts to make as few off-cuts as possible as this will help when setting up for the top cut. Sand the fuselage profile to the line of the paper pattern. A belt or stationary disk sander is an asset, but sanding sticks will work. Make sure to keep the sanded surfaces square to the sides.

(IMG_9806.JPG) (IMG_9807.JPG)
Now reassemble the fuselage block using the off-cuts. Once you are sure of the placement of the off-cuts on the block, remove the aft top section and place a couple of small blobs of hot glue on the top of the fuselage. Put the off-cut into position and use a 1/16" pin through the drilled alignment holes to pin the piece on. Before the glue hardens, (seconds!) check that the saw kerf is about the width of the blade to keep the blocks square and that the cut-off is flush to sides of the block.

Attach all the remaining blocks using hot glue and pinning them as able. The fuselage block should now be square again with the paper pattern on the top and (mostly) intact.

Excellent tutorial Frazer. I await further posts.

Lou

Rough cut the top view of the fuselage

(IMG_9813.JPG) (IMG_9814.JPG)
Remove the pins to keep metal away from the saw blade. Cut to the waste side of the lines as before and sand to the lines .

(IMG_9816.JPG)(IMG_9817.JPG)
Carefully pry the waste from the fuselage block using a flexible putty knife. Avoid a sharp blade when doing this. The hot glue should release fairly easily.

At this point you have the fuselage ready for carving the final shape.

Fuselage guide marks

(IMG_0105.JPG) (IMG_0106.JPG)
Using an HB pencil, connect the alignment holes using a thin, flexible straight edge. Make the mark lightly so as not to create a grooved line in the wood.  Also mark out major features such as the cockpit openings, cowl lines etc. You can free hand the lines on the nose as required. Note that the propeller shaft on this aircraft (and most others) does not always coincide with the intersection of the centre lines. On this aircraft the propeller shaft is slightly above the intersection and was marked with a pencil dot and later with an awl point.

Fuselage cross section template
(IMG_0107.JPG)IMG_0112.JPG)
This model has a simple cross section that is only shown on the front view. I made a paper template by cutting out the front fuselage section on the plan and then cutting it in half. The rest of the fuselage shaping was done using reference photos from the web.

Quote from: lastvautour on June 12, 2022, 10:10:14 PM
Excellent tutorial Frazer. I await further posts.

Lou

Thanks Lou. Building the model is the easy part ;).

I will keep posting as I complete the tutorial segments.

Fraser

Excellent work Fraser. The personal history is very nice touch.

Will follow till completion.

Cheers

Gordon

Thanks Gordon. I will see the project though to the end too. Just not too fast is all.
Fraser

 Fraser ,

Checked out the internet. A very nice looking aeroplane.

Cheers.

Gordon

Reducing the wing blank thickness
The wing can be thinned using a hand plane, bandsaw or handsaw as available to just under 1/4 ". To plane it to thickness, the wing is double side taped to a work surface and planed down to its thickness.

I used a table saw and I attached the wing blank to a sturdy and straight stick with double side tape. I set the saw fence to 7/32" from the blade and I made a few passes raising the saw blade until it was through the full thickness. (IMG_0195.JPG)

You may see that the wing profile has been cut out already. On consideration it is better to thickness the wing while it is still in a squared flat block as it makes handling much easier.

Applying the paper templates to the wing and tail blocks with reference holes

(IMG_9789.JPG) (IMG_9790.JPG) (IMG_9803.JPG)

Now apply a thin layer of glue as before to the top of the wing block and apply the plan of the wing. I defined the block top as the smooth side since future work thinning the block will be from the bottom side.

Mark and drill the four reference holes as shown . Two define the centreline and two more are reference points located at the outer end of the ailerons.

For the tail surfaces, note the grain direction on the maple scrap used. It is best to have the grain running parallel to the span of the horizontal stabilizer and to the height of the vertical fin. This is far stronger and actually mimics the direction the spars run on the real aircraft.

Rough cut wing and tail surfaces

(IMG_9796.JPG) (IMG_9795.JPG) (IMG_9811.JPG)

Using a bandsaw, scroll saw or coping saw the wing blank is sawn out. Here I am using a scroll saw as the wood is thin and easy to cut.
Cut to the outside of the line as shown. Sometimes it can get a bit confusing if there are other lines in the vicinity that can pull you off course. Pausing and standing back to check your progress can help you refocus on the line to cut. Notice the bright light close to the blade and the sharp shadow it is casting. It will help you to keep track of the blade as it cuts as well. Also the air blower helps keep the area clear.

Cut out the tail surfaces using the same technique . A small cut at either end of the centreline on the horizontal stabilizer ensures that the centre is not lost during further shaping and thinning. (IMG_9818.JPG)

Sanding the wing and tail to the line.

A stationary belt sander is a great tool to trim and shape parts. It can work as fine as splitting a pencil line or can remove the waste wood around a large bock very quickly. Here, the horizontal stabilizer has been sanded to the line using a belt sander. (IMG_9818.JPG)

Remove the paper patterns from the wing blocks. Use a heat gun (hair drier) to soften the glue under the paper and scrap it off with a putty knife.(IMG_9821.JPG)

Coming along nicely Fraser.

Lou

Thanks Lou. Like tying your shoe laces, it's actually easy to do but difficult to describe the process.
Fraser

Wing guide marks

Some of the marks can be measured from the plan while others are made using a general rule-of-thimb method to define the airfoil.

First a centreline is drawn on the wing connecting the alignment holes with a line on both top and bottom.  It is also marked on the verticals of the leading and trailing edges.(IMG_9921.JPG) (IMG_9923.JPG)

A measurement from the wing plan center line to the point that the wing starts to sweep forward and back is taken with a compass. Transfer the tick marks to the leading edge and trailing edge of the wing as was measured from the centre line. Connect the ticks with lines fore and aft (wing chord) and vertically along the thickness of the leading and trailing edges.

Mark a line at the wing tip alignment holes parallel to the centre line of the wing on both top and bottom. I used a sliding T bevel gauge for this. (IMG_9924.JPG)(IMG_9925.JPG)

Wing lower surface layout for taper

The Orta has an interesting wing. It is a straight wing with no dihedral typically made by raising the left and right wing tips up a certain amount. Dihedral is a stability design found on nearly all aircraft. However, it looks like the way the Orta's wing was designed, the lower surface tapers from the root to the tip while the upper surface remains straight, creating a type of dihedral.

This tapering is easy to do. Double side tape the wing, bottom side up, onto a suitable length of wood to act as a holder while planing. Looking at the plan, the wing tapers in thickness from the root chord lines drawn in the step above.

Mark point on the front  face  of the wing leading edge tip chord-line half way between the top and bottom surfaces.  Now on the front face of the wing leading edge, draw a line connecting the bottom root chord to the tip chord line the halfway mark. You should have a taper drawn on the from leading edge from root to tip. Repeat on the other wing leading edge and on both wings trailing edges. (IMG_0205.JPG) Shown partial planed. Sorry I forgot to add the arrows for a few pictures, but you are basically drawing a slope from the wing root to the tip to define the lower surface .

You should now see a wedge of material that needs to be removed from the lower wing surface.

Wing lower surface -  planing the taper.

Using a soft (HB) pencil, lightly mark chord wise lines (lines running fore and aft)on the wing spaced about 1/2" apart between the tip and the root chord line. Straightness of the lines nor the spacing of them is not critical. Draw them free-hand and don't press down on the pencil. These lines will be used to control where you are removing material with the plane and allows you to control the taper.(IMG_0199.JPG)

Work the handplane on the wing moving from the root line to tip direction. Initially hold the back of the handplane (heel) up so you are just shaving the surface of the wing about 1/2 inch back from the tip.

Take a look and you should see that one or two of the lines have disappeared. This is the start of the taper. If the lines are partially gone and only the forward or aft portion of the line remains, you are removing the material chord wise unevenly (tilted across the wing). Take a few more passes with the plane and adjust your stroke to favour the portion of the  marks that are still remaining. This should even it out. Still keep the heel up to work only on the end of the wing or now.

Remark the missing chord wise lines again in the area where you have removed them. Now raise the heel a small amount and plane again. You should see that you have again removed the new lines and probably some of the other lines you marked originally . Continue remarking and planing the wing with progressively longer strokes. Now check the sloped line you drew on the leading and trailing edges. The line should be parallel with the planed surface. Use this as a gauge to determine whether you need to adjust the angle of the cut you are making to bring the planed surface match the lines slope. Mark, plane, check repeat.(IMG_0203.JPG)(IMG_0204.JPG)

You will eventually reach the root chord line but don't shave it off. If you shave it off, remark the line accurately and try to avoid removing material from the centre part of the wing beyond that line. (IMG_0205.JPG)
The picture of the plane sitting on the wing seams to look totally tapered beyond the root cord line, but it is an illusion from the photo. (IMG_0206.JPG) Repeat on opposite wing.

When done, remove the wing from the board. Here is the final wing taper showing how the dihedral was formed. (IMG_0207.JPG)
Wing upper surface airfoil layout

Wing upper surface airfoil layout and guide marks

A generic curve for the top of an airfoil can be achieved using guidelines drawn on top.
All of the marking made now will be only on the top surface of the wing. The bottom wing surface remains flat.

A bit of measuring and arithmetic is used to lay out the guidlines. The airfoil is roughly in thirds: leading edge to wing top surface and trailing edge to wing top surface.  Measure the chord of the wing at the root and divide by three. (1.5" / 3 = 0.5" = 1/2"). Do the same at the cord at the tip where the last rib would be, that is at the alignment hole in the wing tip. (1.25"/3 =0.375" = 3/8")  Ignore the rounded tip as it will form its shape as the wing is shaped.

Mark the 1/3 divisions on the root chord (1/2" spacing) and tip chord (3/8" spacing). Draw a pencil line connecting the forward root chord and tip chord marks along the length of the leading edge. Now mark another line span wise along the leading edge halfway between the leading edge and first 1/3 line. The leading edge is a steeper curve from the nose to the first mark and flattens to the 1/3 line where the wing is relatively flat, and this will help mark the shape the leading edge curve. Do the same on the other wing. It is a one piece wing, but there is still a left and right wing. Make sure to mark the wing into thirds on the centre section ( the straight section between the two wing halfs)

Now do the same with a 1/3 line for the aft part of the wing to define where the trailing edge meet the upper part of the airfoil.(IMG_9927.JPG)

PAUSED for now
I will have to pause work and recording of the Orta build due to an unforeseen circumstance. Shortly after I started a vacation, our neighbour discovered that the dish washer had flooded the kitchen. Now that I am back, the repair of the damage is underway but it will make it difficult to provide construction updates. 

I will resume the construction  when the kitchen is in a usable state. Sorry about the delay in updates.

Fraser

So where did I leave off.... Its been a bit of a break for summer vacation and kitchen repairs, but I digress...

Wing airfoil shaping with block plane

Now that the guidelines for the airfoil have been marked out, it is time to shape the wing. Again I am going to use a nice sharp block plane to take even and thin shavings. I find it best to work a few strokes on the left wing and then take the same number and position of strokes from the right wing. This will help keep the material removed symmetrical.

I usually start at the leading edge. I've shaded the area where I will start with. Use an HB pencil or soft charcoal stick as it gives a nice dark mark that is easy to renew. Shaping will initially start with the upper forward edge of the leading edge and work the length of the wing with the grain. In fact all work for this part is moving the block plane with the grain. Take a few stroke with the block plane held at a constant shallow angle to the chord of the wing. Now take the same number of strokes on the opposite wing leading edge. Change the angle slightly flatter to remove the angled corner to produce a faceted shape of the leading edge . Now do the same on the opposite wing.  Use the charcoal to mark the facets to give a clear visual to help in making the cuts.

The idea is to gradually work the leading edge to get a multifaceted curve back to the first "third" mark on the wings aft of the leading edge centre mark. By making only small facets at this point, it is easier to achieve good symmetry of the wings and to get a gradual curve from the centre of the leading edge to the top of the wing. 

When you have a nicely facetted upper surface leading edge, flip the wing over and give the lower leading edge a few strokes to facet the lower leading edge.
When planing the wing, do not remove any material from the very front edge or trailing edge of the wings as this will change the plan shape of the wing.

Now work on the aft third of the upper surface. This part of the wing, although slightly curved on an actual wing, can be planed to a flat wedge from the aft third at the top surface to the trailing edge. Use the charcoal frequently to make slash marks on the planed area as you remove material to give you an indication of the progress of the material removed. Plane until the wedge slope forms a surface from the aft third mark to a consistent trailing edge thickness of about 1/32" from the bottom of the wing. If it gets too thin, it gets very fragile, especially in softer woods.

Now the wing is ready for further shaping with sandpaper.

Wing airfoil shaping
more pictures

Wing airfoil shaping with sanding stick

Make a sanding stick from a piece of wood 10" long and 3/4" square. Use double sided tape or glue to attache a 3/4" wide strip of 80 grit sandpaper (course) to the length of the stick.

Look at the wing from end on and you will see that you need to blend all the facets into a fair curve on the upper surface. Use the sanding stick as if it is a violin bow across the chord of the wing. You do not need to apply a great force on the sanding stick. Work the wing surfaces equally left and right gradually blending the wing surface into a smooth curve. Don't work on getting one spot to the right shape, rather work the whole wing along the span to get a nice smooth shape. Notice in the  picture that the wing that is partially sanded has a dirty and clean surface. The very top surface of the wing is barely touched and marks will remain there until final sanding. Work on blending the center section cut out and it does not come to a sharp trailing edge, but is a rather blunt curve.

When you are satisfied with the overall smoothness and shape of the wing you can sand it to 220 grit. I use a 2" square of sand paper double taped to a square of "craft foam" sheet. This is an inexpensive foam sheet that is fairly dense yet flexible that you can get from a dollar store. It makes for a great model sanding pad.

Work the sandpaper pad down the length of the span with the grain until you have a smooth wing, top and bottom. At this point there is no need to go finer in grit as sealing and primer will adhere better.

The wing is looking good Fraser.


Lou

A terrific tutorial Fraser.

Well Done.

Cheers

Gordon

Thanks guys. I am getting back into the swing of building, recording and writing about the build. More to come.
Fraser

Shaping the horizontal stab and vertical fin

The stabilizer and elevator are generally a non airfoil shape on small aircraft like the Horta. The fixed portion of the stab is usually flat with a rounded leading edge while the elevator tapers to a fine trailing edge from the hinge line.

Mark the middle of the trailing edge of the elevator. Now mark the line on the top and bottom of the stabilizer to define the hinge line of the elevator. Mark guide slashes no the upper and lower faces of the elevator.

Using the 80 grit stick, taper the elevator top and bottom from the hinge line to the centre of the trailing edge. The tail surfaces are only about 1/16 thick so it does not take a lot of effort. Also since maple was used for the parts here, it can be sanded to a thin taper. Be careful, as it can get really thin and sharp!

Lightly sand a half round along the leading edge

To ensure the hinge line can be found later, I lightly notched the tips with a razor blade. Give the parts a final sanding with 220 grit.

Use the same method to taper the rudder on the vertical fin.

Fuselage shaping

Shaping the fuselage is done with pretty much the same tools. I don't use the block plane as the fuselage is small and more sculptural in form.

Print out a plan so that a template of the fuselage cross section can be cut out of either card stock or paper then glued onto cardboard. This airplane pretty much only needs the one template at the section between the two cockpits. The nose is circular and the aft fuselage is pretty much rectangular.

Use the centre and longitudinal small drill holes to mark reference  lines on both sides and top and bottom of the rough cutout. Don't press hard enough to groove the wood, a light touch with the HB pencil is good.

It is not too critical where to start carving the shape, but I like to start at the forward fuselage. My eye tends to fill in the detail from nose to tail better.

Make faceting cuts with a knife to start the radius of the fuselage at the engine cowl area and nose. Use the template to see that you are removing material in the right places. Now continue to remove material with the flat 80 write sanding stick. Again, move the stick like a violin bow across the grain of the wood to gradually remove material.

Work all areas of the model now to ensure symmetry and fair lines. If detail areas need work, then a knife can be used to work that area though. Re-mark the centre lines as required if they fade.

Do not remove the material at the centre and side guidelines as the profile shape of the fuselage was set when you roughcut the block and sanded to the edges earlier on. Removing the lines with a blade or heavy sanding now will change the shape of the model substantially. If this happens, it can be fixed as will be seen later.

Checking for fair

Fair lines are a term used to see that the shape your are creating is smoothly curved and looks smooth to the eye. Take a long flexible stick and bend, by hand, a long curve like a bow into it. If you sight along the length of the stick it should be a nice curve without noticeable bumps or dips. That is a fair curve.

It is used in boatbuilding (such as a kayak or dingy) by looking along the length of the boat and sighting the curve as you move along the hull. If the curve of the part you are looking along makes a sudden bump or dip that is not part of the plan, it is out of fair. Removing or adding (filling) material is done to get the line back to fair.

This is also how the shaping of models works. The side of an airplane may start as a fair curve at the nose, flatten at the doors passenger area, then curve back to the tail. Or there could just be a straight line that smoothly transitions into another straight line. In other words, the fair line is defined by the shape fro the plan. If the line is not fair and it should be compared to the plan it can be fixed.

As can be seen in (IMG_0128.JPG), I under cut one side of the fuselage and it is too flat. I'll add a piece of wood to get the line back fair again. Also in (IMG_0127.JPG) there is a divot that will need filling to make up for the errant cut I made.

Adding material to re-establish the shape

For the large flat area where I cut too much material at the very start, I will glue a thin strip on using carpenters glue. Once the glue dries I carved and sanded the repair down to a fair curve to match the other side. Checking the model to the plan now shows that it is the right shape and symmetrical.

Don't forget to redrill the side ref hole that is now covered by the repair. Drill from the opposite side using a small pin drill.

Mark out the cockpits

Refer to the drawing to get the cockpit locations and shapes. I free handed the cockpits and shaded them with pencil for further shaping to come. The plan does not show the cockpits too well from the top, so the opening shapes extrapolated from the side views.

Aft cockpit headrest
All of the pictures I could find of the aircraft that I am modeling show that it had a headrest for the aft cockpit. The plans did not show it so I added one to the model.

I drew the part into a 1/4" thick block and cut the top plan view shape out. With the part double taped to a popsicle stick I rough carved it the sanded it to shape 
I'll glue it in place after I have carved out the cockpits.

I just realized that i had not put a photo of the aircraft I'm building here.

So here is the actual pilot and aircraft and another with the pilot (in the new colours) discussing something with a (probably) mechanic.

Excellent tutorial Fraser . Easy to follow.

Between Lou and yourself the Tutorials should enable anyone to take up the challenge and turn out a model to be proud of.

Well Done both of you.

Cheers

Gordon

Thanks Gordon. Even if this model never gets built by another modeller, the techniques are transferable to almost any model.
Fraser

Cockpit carving

Caution: You will be using sharp tools with small parts. Ensure that the work is held securely in a small vise with padding to prevent damage to the outside of the model. Sharp tools will cut easily. If you are exerting yourself to perform the cuts, re-evaluate the sharpness of the tools. Never cut towards your body or use your body to support the work. Small cuts using the thumb and fingers to control the blade and amount of travel is important. Don't use stabbing actions with a folding knife.  Always look where the blade will go if you slip or the part splits during the cut.


Now is a good time to carve out the two cockpits. It is tempting to use a large drill to hog out the material, but this would probably end up in grief if the bit catches and destroys the model so far. The walls get too thin and there is no real good way to support the fuselage for heavy drilling at this stage.

A good carving knife and a small corner gouge are what I used. The knife is a folding pocket knife by Flexcut called the Whittlin Jack. The two different blades, detail and roughing, are polished and sharp right out of the box. It is my go to carving knife. The "V" gouge is also by Flexcut and is a palm style with interchangeable handles. They are not inexpensive tools, but will last a long time and keep a keen edge.

A good Swiss army knife with two smaller blades will work quite well.

Use the tip of knife to score vertically  around the cockpit outline to a depth of about 1/8".

Now cut inside that scored line about /16" inch inside of the cut starting across the grain at either end of the cockpit. On this cut, angle the blade over about 45 degrees so the tip will intersect the bottom of the previously made score cut. Don't try to do the entire perimeter around the first score line. Work the tip of the knife for a short distance across the grain to remove a small sliver of a wedge from the inside of the cockpit. Basically you are doing a chipping cut.

Make the same cut at the opposite end of the cockpit. Now cut using the same method on the sides of the cockpit. Try to avoid prying the pieces out with the tip of the knife, but try and get a chip to come away cleanly.  Leave the side walls a bit thicker as it will be easier to remove more than fix the side wall if it breaks out.

Keep working around the perimeter to get the waste removed from inside the cockpit until it gets awkward to use the knife only. Now switch to the small 'v" gouge to start removing the material from the centre. I keep pushing it into the waste wood to break it up and remove the pieces with either the knife or gouge as required. Again, don't try to remove larges amounts of wood at a time or go too deep with the tool.

Use a stick with a mark about half the depth of the fuselage at the cockpit to estimate the depth of the cockpit.

When you are deep enough, use the tools to clean up the cockpit to the shape you drew at the start. Course sandpaper on a dowel can be used. You can also use a dremel tool with a small sanding drum to finish it out. On thing to be careful with a dremel is the tendency to grab the adjacent wall when moving it. This results in the sanding drum  rapidly running around the inside of the hole you are trying to finish.

Next we'll look at the addition of a paper liner in one of the cockpits to refine the shape a bit better

Paper filler in aft cockpit (optional)

I was not quite happy with the shape of the seat area of the aft cockpit so I decided to give it a paper liner secured with automotive glazing putty.

Actually you can see the paper in place on the previous photo 0165. You will also notice in the pictures that I have added filler on the fuselage. So the pictures are a bit out of sequence but....well look at filling the fuselage in a bit.

I cut a small piece of regular copy paper to form a rounded seat back for the aft cockpit.

I curled it and kept trimming it to fit where I wanted it. To keep it's shape, I used wood hardener on the paper. This essentially saturated the paper and it became like a composite material. Other stuff could be used as well. Clear nail polish or thick cyanoacrylic glue will work as will carpenters glue. The idea is to create a form that will be held inplace with the auto glazing putty.

Once the coating has hardened and the paper is now relatively stiff, it is held in place with the auto glazing putty. Plastic wood will work as well.

With the paper form removed, apply a small thickness (approximately 1/8" max) of putty to the to the back of the paper and set it into the cockpit back. Press the paper in place until you are satisfied with the position. Ideally there should be some squeeze out. Allow it to set and and the sand top of the paper flush with the cockpit. If there is a lot of paper or filler exposed, remove the bulk with a knife first. When sanding the paper top edge, full the sanding stick towards the wood walls to prevent tearing the paper away.
If needed, add more filler for any gaps or hollows remaining, sanding as necessary.

Filler can be used inside the cockpits to smooth out the carving marks if required. A sanding stick on a dowel will help clean up the cockpit and make them smooth.

Filling defects with automotive glazing putty (or plastic wood filler)

I use automotive glazing putty to fill and fair my models. It fills small to large areas and sands beautifully. It dries pretty fast so many thin coats can be applied and it adheres well to wood, paint and sealers.

A few drawbacks. It scores ( scribing a line) well, but differently than the bare wood. It can chip during the scoring process especially across grain. Also it has a strong smell. Its solvent is acetone and the filler is likely styrene based. It therefore flammable. Since only small amounts are used in modeling, I find it is ok to use in my shop. If you are in a smaller room, ensure you have ventilation.

However it comes in a nice large toothpaste tube with a screw cap. I have used the same tube for a few years, so it keeps well if capped.

Tools.
I have a set of tools used for shaping clay pottery. They are quite cheap ($25 CDN on Amazon, Yasumai 12 Pcs Carving Knife Tool kit Pottery).  They are stainless steel and will last forever. I also use spatulas made from plastic gift cards, dairy product containers or wood craft sticks.

To fill holes like the alignment holes made earlier it works very well. I use the square end spatula to press a small amount into the holes. It only takes a match sized blob to work into the hole, Smooth it off with the spatula leaving it slightly high at the hole. This will allow for shrinkage. Keep in mind the hole should be filled to least 1/8" into the depth. On a through hole like on the wings or other thin sections, it should fill all the way through and pop out on the opposite side.

When the filler dries after about 10 minute, lightly sand the excess filler off until the bare wood is left around the filled hole. As you sand you will notice the filler goes from dark red to pink (or lighter red). When the filler material around the hole has been removed to just "coloring" the surrounding wood grain, you will probably see that the actual filled hole is still dark red. This is good because it means the filler is below the surrounding wood and has not been touched by the sanding.

Apply another thin coat of filler at the hole and again leave it slightly high. After it is dry, sand it lightly again and it should now have filled the hole completely. It will remain the same light red as the  "colouring" of the surrounding wood gain. Carry on to fill all the holes in a similar manor.

Filling shallow dips or contours is done the same way, just use a wider spatula and apply thin coats sanding between each layer. Each layer is checked until the area over the defect is the same color as the area around it and is feathered (smoothed) to the correct contour.

Long gaps such as during the repair done to correct a mis-cut fuselage side earlier are filled and sanded the same way.

Keep filling and lightly sanding the whole model until you are satisfied that is smooth and fair. Go to at least 220-400 grit as a final sanding. The model will be primed and additional filling may be required later.

Also you may notice the sand paper clogs with filler during sanding. To clean the sand paper use a gum eraser on the sand paper and it will remove the clogged filler.

more filling picture

Applying exterior fuselage stiffeners

Stiffeners run longitudinally along both side of the fuselage. The original Orta looks to have been built from wooden frames skinned with plywood.

To represent the stiffener, I constructed one from heavy white card stock (110lb). The strips are 1/16" wide and cut 1" longer than the length of the fuselage. I used a paper cutter, but a knife and straight edge will work. Cut a few extra for the inevitable losses to the floor or other minor disasters.

The strips run from the cowl line aft to the end of the tail and will be trimmed to size once the glue dries,

I used the still visible alignment holes (now filled) to use as a guide to install the strips. Wet the strip using carpenter glue by applying a blob of glue to your finger then pulling the strip through the glue. Make sure enough glue is applied to the side of the strip that will be bonded to the model.

Lay the strip on the models side and apply a but of tension to the strip to straighten it out. Do not pull too hard though, the paper may pull apart otherwise (good thing there are extras right?) When you are satisfied of the location, rub the strip down into the side to ensure a good bond.

After a few minutes look where the front of the strip starts at the cowl line. Use a single edge razor blade to press lightly at the cowl line across the strip, just hard enough to hold the strip without damaging the wood fuselage. Lift the excess part of the still damp strip up and it should tear cleanly at the razor.

Of course this works better if the glue is not set completely. If it has set, you will have to carefully cut the strip across at the cowl line and remove the excess piece with a razor.

I left the tail ends long until the glue fully dried. This allowed me to simply cut the fully bonded strip flush with the fuselage end.

Apply the opposite strip as the first one.

Once the glue has dried, lightly sand the strip and make sure there is no glue squeezed out  along the length.

Note that this also a technique used to simulate wing rib tapes on wings, although I will use a different method later.

Marking and drilling engine cylinder locations on the nose

The Orta has had several engine configurations: 5 cylinder radial, 7 cylinder radial and 4 cylinder inline. This particular one is a 5 cylinder engine.  The discussion on making the cylinders for this model will come later.

Side note: why do radial engines always have an odd number of cylinders, 3, 5, 7, 9? (Single row engines)

Template

Make a template to lay out the five cylinder locations.

Since the engine is five cylinders, a pentagon can be used to equally space the cylinders.
Either using a drawing program, cad, geometry layout with compass or tracing around a pentagon shaped toy draw a pentagon to fit a two inch circle (approximate). Find the geometric  centre and mark it. Use heavy card stock for the template.

Measure the diameter of the location aft of the nose to set the centreline of the cylinders. An easy way to do this is use a circle template (art store) and fit the nose into various circles until the template fits at the circumference where the cylinders will be located.  Due to carving variances, the desired size of the circle for the cylinders may vary.

Locate this circle centred in the pentagon and draw the circle to the template. Make sure the lines to the center are dark enough to see and cut out the inner circle. Cut the template outer size to about two inches in diameter.

You now have a template that can be used to mark out the locations on the model.

Marking cylinder locations

With the template positioned on the nose, trace the circumference around the nose.
Mark the location of the top cylinder on the centreline of the fuselage on the circumference line with a sharp awl. This is #1.

Making sure the #1 is always aligned with the template, mark the remaining four cylinders on the circumference line.

Single row radial engines are built with the top cylinder opposite from the oil sump. So the #1 is at the top and the remaining cylinders are numbered clockwise as viewed from the back.

Drilling the holes

Use a 1/16" twist drill to make the pilot holes. Start with the #1 cylinder as it is easiest to hold the model squarely for this position.  The model is wrapped with paper towel and mounted in a small vise. The smaller pilot will  start easier than the larger bit as it will not catch on the spherical nose very easily. Drill in vertically about 1/8" deep.  Remove the small bit and redrill the hole with the 1/8" bit.

Now rotate the model to get each cylinder location aligned vertical as in the #1 hole and repeat with the smaller bit before sizing to the 1/8" hole.

To hold the fuselage in the vice, wrap it with a small piece of paper towel, not cloth. Cloth may catch on the spinning drill bit and cause a hazard whereas the paper will tear out. NEVER USE CLOTH NEAR ROTATING TOOLS.

Side note answer: Radial engines always have an odd number to allow for the four-cycle firing order to work. All the odd numbers fire in sequence first then the even numbers fire in sequence. This pattern repeats and gives a radial that nice stuttering sound.  For a seven cylinder engine. 1,3,5,7,2,4,6,1,3,5,7,2,4,6

Never thought of using heavy paper for stiffeners. Great Idea Fraser.

Lou

Thanks Lou. It gives a nice sharp definition and the thickness is about the right scale.

Fraser

I usually use masking tape but have to double it up. Heavy bond paper can be beveled if you are careful. Again, thanks for the tip.

Lou

Creating flight control surface lines with a scribe
From a previous post on building the Mosquito Fish hook scribe description
For scribing the lines I watched a YouTube video "Creating scribed detail". The author uses dental tools but I tried another tool. I used a 4/0 fishhook modified and fitted into a x-acto style blade holder. I pinched the barb down with pliers, straightened it slightly then cut it off from the shank. The hook tip is actually triangular in cross section. If you work the tip against a fine sharpening stone you will end up with a triangular facet.  I used 0.003" brass cut to strips as a straight edge that was attached to the model with painters double-sided tape. A light touch works best.
Locate the lines that will define the ailerons, rudder and elevators. Keep in mind that flight control surface lines appear on the opposite side (top/bottom left/right). Starting on the wing, the reference holes were placed at the intersection of the aileron intersection of its leading edge and end rib.

Wing aileron upper and lower surfaces
Use a straight edge to lightly pencil in the lines on the top surface. The leading edge of the aileron on this airplane runs parallel to the wing trailing edge. Mark both the outboard and inboard ends of the aileron. This is a bit trickier because the aileron ends are parallel to the airflow, not square to the trailing edge of the wing.
The only wing surface that is square to the airflow is the leading edge of the center section of the wing. All the future references for the wing will be from the center section leading edge.

An easy way to transfer the ends of the aileron is to use the plan of the wing and cut out the aileron. Now you can use the reference hole at the outboard end to locate the aileron template you just cut out. Mark the aileron ends in pencil. Repeat on the opposite aileron.
Now work on the wing lower surface and mark the ends and leading edge of the ailerons as before. Looking edge on from the rear of the wing, the upper and lower pencil Lins of the aileron ends should be in line. If not, correct it before going further.
Now with the pencil lines as a guide, line up the straight edge on an aileron end line on the top outboard end. Hold the scribe like a pencil and drag it lightly form the leading edge marked out for the aileron back towards the trailing edge of the wing. You are scribing cross grain which is a bit more difficult than following the grain. Use a light touch to go over the line a few times to avoid tearing the grain out. When you have a nice distinct scribed line repeat this on all of the remaining aileron ends, top and bottom.
Now reposition for the aileron hinge line with the straight edge. The straight edge should be parallel to the trailing edge and contacting the forward end of the two lines defining the aileron ends. Scribe this line making sure not to run past the aileron ends to give a nice crisp corner. If you go a bit far, no worry...that is what filler is for.
Repeat scribing the remaining aileron lines.

Rudder and elevator hinge lines
Mark out with a pencil, the scribe lines of the rudder. Note that the rudder has a small portion that runs forward to the leading edge from the hinge line. This is the rudder horn aerodynamic balance panel. Make sure the scribe lines meet there and do not go past to the top of the rudder. Scribe the lines in on both sides.
The elevator does not have balance horns so the hinge line goes tip to tip square to the center line. The central notch that defines the elevator halves is the measure of  the width of the elevator.
I realize this is a long description of what is really a simple process but I unfortunately only provided one photo. :(

Marking pin locations for aligning and mounting the tail surfaces

I like to use .020 inch brass wire pins to mount my wings and stabilizers. This provides a strong and accurate location of the vertical fin and stabilizer pin holes.

Here is a brief description on fabricating the locating pins as used on previous models They are 0.020" brass by 1/2" long. There is a small blob of solder at one end that has been turned using a Dremel tool against sand paper to create a small point. The solder cone acts as a shoulder to prevent the pin disappearing into the hole and the point makes a mark for the corresponding hole.
Vertical fin pin hole alignment method
To locate the pin holes I marked them out on the centreline of the vertical fin where it sits on the stabilizer. After marking the hole centers with a sharp awl I used a 0.025 (#72) drill bit mounted in a Dremel tool to drill two holes about 1/4 " deep into the fin. The pins were a bit too long so I shortened them for this particular job to about 1/4" overall length.
I inserted the pins into the holes and placed the fin in position on the centreline of the stabilizer with the pin tips just touching. When it was in the correct location a little downward pressure on the fin left two small centre points for the matching hole on the stabilizer. Now the .025' (#72) holes for the pins are drilled through the stabilizer.
Now put the transfer points through the stabilizer, with the pints on the bottom surface and align it so the centreline of the stabilizer is on the centreline of the fuselage. After ensuring the part is correctly aligned and not skewed of centre, press it down to leave the centre marks on the fuselage. Drill the .025 inch (#72) holes about 3/8 inch deep into the fuselage.

Cut two 1/2" pins from the .020 brass rod and insert them into the vertical fin. Place the fin on the stabilizer and place the whole assembly onto the fuselage. It should be nice and square. If not, you can adjust the holes a bit with the drill to give a bit of wiggle room for alignment.
Take the pieces apart after the dry fit is good. Use a pencil to mark the top of the vertical fin. A small "X" on the centreline will suffice. Keep the pins where you can find them for later assembly

Sealing and Priming the model

Since we have the major components cut for the model, it can now be sealed and primed.

First I brush a couple of coats of nitrocellulose dope to the bare wood to act as a sealer /filler, sanding to 220 - 320 grit between coats. A great source for this type of dope is...clear lacquer nail polish from the dollar store! It is the same stuff as nitrocellulose dope and it even comes with a brush! Plus the small quantities are perfect for small projects like this.

Prior to applying a finish to the surfaces to be glued, cover them with small pieces of masking tape. The masked areas are visible on the pictures of the fin and stab. Don't worry if there area is a bit big, as a second coat of primer after assembly of the tail will fix that.

Since the parts already have an assortment of holes, it is easy to insert toothpicks into them to hold the parts for painting.

Apply the first coat along the grain and the second coat across the grain. Wait about 20 minutes between coats.

After drying and sanding smooth, now apply the primer. I use a spray automotive primer /filler that is sandable. Ant brand will do, just make sure it is a sandable, filler primer. I t comes in various colours. I generally use grey, but I also use the off white as well depending on the top coat colour. The primer should be well shaken and when applied will go on as a wet looking coat. Don't apply too heavy to prevent runs, but a a short spray along the full length of the object about 8" away works well. The product I use looks somewhat rough when wet but dries quickly to a nice even flat finish.

Look for any imperfections in the models surface and apply thin body filler as before over the areas and sand them back.

You may notice that the bare wing has had the rib stitching details added before priming and the fin and stab have had the stitching added later. Either order is fine and will work in the next step in adding the rib stitching with glue.

Wing rib simulated stitching-tape using glue
Ref article 1/48 Fiesler Storch August  23 2019 replay
Photo from web
The following information is from a post from my 1/48 Fiesler StorchcReply #1 on: August 23, 2019, build. It describes the process for building and using the wing stitching jig with a ruling pen and thinned glue.

I made a small fixture that essentially allows me to follow a straight and perpendicular line across the wing surfaces. General construction of the fixture is two 1"x 0.5"x 10" rails screwed to a board and spaced apart the width (chord) of the wing plus about .5" extra width. I double side taped a copy of the wing plan to reference the rib spacing on top of one of the rails. I placed the wing in reference to the drawing on some spacer blocks to get the top surface to just below the tops off the rails. Double sided tape is used to secure the spacers and wing together on the base. Small pieces only required. Tape of areas that do not have rib stitching ie: smooth panels.

I mixed a small quantity of water proof wood glue  (Elmers glue, PVA that was on hand). The waterproof glue seams to be a bit better at remaining as a raised line. About 2ml of glue thinned with 0.5 ml of water (few drops); enough that it drips off a toothpick. Now using a small square that spans over the wing and sits on top of the rails, line it up with a small offset from the drawing to allow for the pen width. Dip a ruling pen into the glue and touch off the excess. Now draw the pen along the edge of the square to mark the rib. A ruling pen can be adjusted to get the line width you want. I set it about 1/32" wide. Continue along making rib lines, refilling the tip as needed. Since the square is sitting above the wing surface, there is no risk of smearing the wet glue and you can go over a rib again if needed. When done, peel off the tape and continue to finish the model.....

smearing the wet glue and you can go over a rib again if needed. When done, peel off the tape and continue to finish the model.....
Building the fixture took about an hour, but it can be used to make future models.

Tools needed:
Ruling pen
Small square
Simple fixture as described above

Materials:
Double sided tape
PVA type glue thinned with water
Regular masking tape

For this model, I used a photograph to count the ribs and divided the number rib spaces into the model measurement to get the spacing for the model. This is also how the spacing for the stab and fin was calculated. For the wing  from the plan, there are 10 spaces between center of the wing to just outboard of the aileron end. The measurement is 3.785" / 10 = 3/8" spaces.
For the stab the spacing is 1/4 " and the fin is 3/16".

Tape the area along the leading edge about 1/4" wide to provide a clean line to define the forward end of the rib stitching. Raise or lower the wing to provide a clearance of about 1/32" from the square to be used and the top of the wing surface ( I used a popsicle stick under the square here). Align the center of the wing to the first line of the markings with the center leading edge against the jig to ensure the correct alignment of the wing.

Mark the ribs as described above. Repeat for opposite wing half and lower surfaces. Position the fin and stabilizer in a similar manor and apply the glued lines.

Assembling the tail

Since the detailing of the fin and stab are complete, I decided to assemble the fin and stab to the fuselage.

Since we have the alignment predetermined by the pins previously fitted, it is a simple matter to assemble the parts.

Insert the two pins (kept from earlier) into the fin and apply wood glue to the base of the fin. Insert the pins through the stab, ensuring the stab top surface is up and check the fin for vertical square. Let it dry for about 1/2 hour.

Now apply glue to the notched surface on the fuselage where the fin sits and insert the exposed pins into the holes.  Check that the fin is level and square to the fuselage viewed from the back and is not skewed left or right sitting on the fuselage.Clean up any glue squeeze out before it dries fully the set aside to dry.

Once dry, apply a bit of body filler to any gaps, most likely at the centre leading edge to fuselage joint and file or sand smooth.

The Landing Gear.
This will be a fun challenge coming up...Jigging and soldering up the brass landing gear assemblies..........

Soon....
Fraser

Landing gear and strut fixture

I have taken quite a hiatus from writing this tutorial. I turns out that the seemingly simple model  airplanehad landing gear that was the most challenging part of the build. The landing gear is incorporated into the wing support structure and is comprised of five struts per side. There are multiple soldered connections as I like to use brass tubbing and wire for gear construction. The three dimensional aspect of the gear means that I needed to construct a jig to fit all the parts together before I tried assembling them to the model fuselage.

Since all of the components except the vertical gear struts are at a diagonal to any view of the aircraft, it is a challenge to determine the actual length of each strut.

Add to the challenge there where different configurations of the landing gear geometry depending on the development of the Orta. Some variations where found in the pictures of the actual aircraft that did not match the three view plan I had.

So staring off, I designed a holding fixture to represent the fuselage and wing attach points based on the side view of the fuselage. IMG0996

I went a bit overboard and drew up a 3d model in Sketchup based on dimensions from the plan and the as model fuselage as it was built.

Most important considerations were the: cross section of the fuselage, the location of the lower fuselage attach points, the height of the bottom of the fuselage ( when level) above the ground, the height of the axels above the ground, upper fuselage attach points and wing lower surface above the ground.

I drew up the points in Sketchup but in fact it was just as accurate to build of the fixture by direct measurement.
.
I made a side view block as shown in IMG 999 from material the thickness of the fuselage width and the height of the axel to the bottom of the wing.   It was hot glued to a base block, making sure it was positioned squarely. IMG 1001

I used dividers to mark the width od the gear from the fuselage side drawing and transferred it to the wooden block. IMG 1003

The centre of the vertical strut was marked square to the block approximately mid point IMG 1006

The fuselage bottom was marked reference to the axel and the attachment points marked on that line either side of the vertical reference. IMG1007

The upper wing strut attach points on the fuselage were measured up from the bas and the positions of the attach points marked on the line.IMG1008 and IMG1011

Problem. The aft end of the upper strut is actually farther aft on there aircraft than the drawing shows, so I had to adjust the mount point aft based on a photo. IMG1012.

I used a sharp awl to make a pinpoint at each attachment. This is repeated on both the left and right sides of the fixture.IMG1011

pictures ref fixture

Wing lower surface Fixture

After the gear points are marked on the base and fuselage points, a representation of the wing lower surface is attached to the top of the fixture. This will allow for accurate positioning of the wing and vertical strut. IMG1037

A thin plywood was used to represent the centre flat portion of the wing lower surface. It is attached to the top of the fixture so the lower surface is the plan measured distance from the axel to the wing bottom. A line is drawn on the lower surface to mark the fore/aft location of the wing mounting points the measurement of the points are taken from the drawing and marked on the surface left and right.

The wing fixture section is attached to the top of the fuselage fixture using small 1/8 dowels to allowing it to be removed as required after finishing the gear soldering. Make sure to mark the forward direction for reference.

Drill a 0.020"  hole at the two wing strut attach points on the fixture and the bottom of the fixture but the end of the vertical strut. The upper and lower holes should be in vertical alignment and will be key to fitting up the gear parts.

Making aerodynamic flattened brass tubes
The struts of the wing and gear structure are aerodynamic shaped tubes. To make them I use brass tubing with a core of 0.020" brass wire. If the end of the strut is to be attached by adhesive to t wood, I leave the wire inside about 1/8" long to use as a pin.

After the tube is measured for length, a piece of wire about 1/4" longer than the tube is inserted into the tube. The gear uses 0.062" and 0.096" brass tubing as required for the particular part.

To flatten the tube, use a flat faced hammer and a steel plate as an anvil. Using even steady flat blows to the tube flatten it until it has firmly pinched onto the wire inside. Trim the wire as needed for the particular part location. IMG1034, IMG1035, IMG1039, IMG1040

Measuring, cutting and fitting struts

With the attach points marked on the fixture for the various struts, now the actual length of the parts can be directly measured.

To do this, use a [air of dividers or compass points to measure between the marked points.IMG1031

Here the centre wire for the vertical gear strut is in place between the lower wing attach point and the lower point, which is the axel height. The wire runs long an after everything is soldered up, it will be the pin for the wing attach and the bottom will be bent 90 degrees outboard to form the wheel axel.

The divider is set for the length of the intersection of the vertical strut and the lower aft gear leg mount point.

Transfer the measurement to the appropriate sized tube and cut it to length. The best way I have found now for cutting small brass tube is with a mini cutoff saw. They are available from harbour fright in the states for the best price. Amazon carries them, but they are more expensive for the same saw.

Second best is a serrated cut off blade fitted to a Dremel tool or a fine modelling pull saw. You get nice clean cuts with these tools.

Using a side cutter or sprue cutters does work well on wire, but tends to crush the tubing closed. If you use them allow for a bit of extra length to file the end flat and open the tube up.

Insert the wire core and cut it a bit long to form a pin for attaching to the model. If it butts to another brass part that will form a soldered joint, cut the wire flush to that end of the tube. IMG1041

Keep cutting and fitting the various parts until you get a good fit in the fixture and solder them together in small groups as you go.

Soldering brass struts

Solder is simple. Clean, flux, heat, apply solder. How you accomplish the steps will determine the strength and tidiness of the joint. Solder is amazingly strong for the structures used on small models like these.

Once you have settled on the fit of the parts, individually clean the parts joint area with a small piece of scotch-brite or fine sandpaper. This gets rid of oxides and give a bit of tooth for the solder to bind into.

Set the parts into place and if required hold them with self closing tweezers. I use tweezers mounted on metal bases that are used for jewelry or electronic soldering. They are not expensive and I find that they are very useful for modelling in general.

Apply a SMALL amount of flux at the point that will be soldered. The point on the end of a tooth pick is about right. With heat and flux, the solder will flow where the flux is towards the heat. This allows a very small area to be soldered with control. Too much flux is not helpful.

Use the sprue cutter to cut a small piece of fine electronics solder wire. The cut piece will make a match head look like a boulder in comparison. Really small... about the size of a typed letter "O" is a good starting point.

Set the small piece of solder on the joint to be soldered. The flux will provide a bit of stickiness to hold the solder in place.

Use a small soldering iron such as used for electronic projects. Touch the tip to the joint and try to heat both sides of the joint. If done correctly, both parts will heat quickly, the flux will melt off and the solder will suddenly melt and flow into the joint. when this happens remove the solder iron. The pieces will cool quickly. Total time with the sobering iron on the parts is about 2 seconds for such small joints.

Practice will make for more proficient joints. Variations in the first four points will affect the quality of the job.  If it goes bad, the parts can be cleaned and easily reworked again. It would be another entire tutorial on how to solder small parts, but I would recommend a youtube  video that will help. Almost all solder is lead free and works well enough.

www.youtube.com/watch?v=-7D3M3VqCUg

Completed and Soldered landing gear and struts in fixture

These pictures show the completed struts as they are soldered into the fixture. While on the subject of fixtures, why not call them a jig? The convention I know is that a jig is used to guide the tooling during the manufacturing process. A fixture is used to hold something into alignment during manufacture. Example: Jigs can be used to guide a drill while the part is held in a fixture. The terms get used interchangeably and probably both are valid as long as the intended function is known, but I digress.

The last picture IMG1064 shows the fixture with the struts compared with the CAD drawing for fun. It was fun to see the real world meet the virtual world here.

Looks great Fraser.

Lou

Thanks Lou. In retrospect the "simplicity " of the design did not take into account the fairly complex geometry of the landing gear and wing support.  Several online  pictures of crashed Orta's usually showed the wing askew to the fuselage with the gear collapsed.
 
Perhaps not the best model for a novice, but it is an interesting build. It shows the value of making a fixture separate from the model for more complicated sub assemblies.

Regards
Fraser

Marking holes under wing for struts

Once the gear components are soldered together in the fixture, the holes for mounting the wing to the upper forward struts can be located and drilled.

Remove the top of the jig. You will now have a flat surface with a centreline to help orient the wing and the tops of the struts will locate the holes. IMG1268

On the wing fixture, measure the distance between the two wing mount holes. I used a calliper to make get the actual dimension. Dividing by 2 will give the center of the wing to set a compass to mark the points on the wing.

If you only have a divider, you can geometrically find the exact center to draw the points. The notation on the picture shows how to bisect the measurement to get the center. Basically mark two points "B-B"on a paper with the divider set to the wing mount point measurement. Connect the dots with a line. Set the compass to any measurement "R" greater than the estimated half way between "B-B". Set the compass on B and strike an arc.Do the same on the other point B. Connect the intersecting arcs with a line "A-A". The crossing point is the exact center of line "B-B". Call it X and set the compass on X to measure "X-B"

Set the compas on the center of the wing, in this case the previously made wing tape line. Position the point 5/16" back from the leading edge and make the two arcs on the wing lower surface. Measure back from the leading edge and this point will be the wing mounting holes. IMG1277 IMG1276

Hold the wing in place on the fixture to check that the pins line up with the marks. IMG1278

If all is good drill a 0.020" hole about 1/8" deep at each point. If you go thru the wing, just fill the holes on the top later. IMG1280

Trim the tops of the wires on the strut to 1/8". The wing should now site nicely on the fixture held by the two struts.IMG1279 IMG1281

The aft wing struts are located fore and aft on the drawing and transferred directly to the wing and drilled as before. IMG1283

pictures to mark wing mount holes

Mounting landing gear to fuselage - scribing reference line on cowl

Before we can mount the gear, the mounting holes need to be located on the fuselage. To get a good reference point on the fuselage, the firewall / aft cowl line was marked on the fuselage. I used a strip of thin brass to provide an edge to draw the line on the fuselage.  A single edge razor blade is used to cut the line into the model. For a surface like this. I simply place the blade on the line and apply pressure to the blade while I roll the blade over the line. I don't drag it as it is not as controlled and may also tear the paint finish. IMG1286 IMG1288 IMG1289

Mounting landing gear to fuselage

Use the divider to locate the aft strut mount hole at the bottom of the fuselage side aft of the cowl line. Drill the .020" hole at this point on both sides. IMG1291

Remove the gear from the fixture. Hopefully there is a short .020" wire pine on the aft lower strut, upper end and the aft upper strut lower end. Insert the lower strut end into the hole on the fuselage. The lower forward strut is located at the cowl line bottom edge. There is no pin here and the strut can be manoeuvred into position over the cowl line. IMG1296 

With the vertical strut vertical to the fuselage side, mark the upper aft mount point and drill. Now there are two pinned points on the gear and the forward struts are located. Again the those struts are not pinned, but will be glued to the fuselage side. You could make them pinned, but it was more difficult to position and drill with them if there is a small amount of distortion in the assembly. IMG1297

Both gear assemblies can be held in place to see how they fit. I also made a small fixture of the wing center section to hold the upper struts at the correct location while the fit was checked. The struts were then glues into place at the four attach points with thicker CA glue. IMG1295 IMG1298

Note in this picture the landing gear axels are still straight down and can be bent outward 90 degrees to form the axels. IMG1299

Making Seats

So after all the work on the landing gear, I did take a break for awhile...

But I did make a couple of cockpit seats out of card stock and CA glue IMG 1410

I I drew a pattern based on a wicker seat used in the aircraft of the era. It is simply heavy card paper cut and shaped around a pencil to curve it.  CA glue was used to hole it together and then it was covered in CA to essentially plasticize it. The back seat is slightly narrower than the forward seat which holds two people. After they were painted, I mounted the aft seat on a thin block to raise it as the cockpit was a bit too deep. They were glued into the cockpits after the model was painted. IMG1438 IMG2228

Marking and Making Wing Struts
Meanwhile, after completing the gear and wing strut....ha....I was looking at actual aircraft pictures again and discovered I had not built the actual struts for the darn wing. The three view I was using did not show two forward struts that tie into the fuselage and at the top of the gear strut.  They are hidden from view due to the structure and geometry of the gear assemblies.......HA....

I had the aft strut locations ok from the drawings but the forward wing strut was hidden. The lower end of the strut is centred between the lower gear in line with the vertical strut. IMG1420 IMG1421

Measure the length between the fuselage point and the inside angle of the joint on the gear upper end. Make a streamlined brass strut as was described before, but only put a .020" wire in the one (lower) end. Glue it into the hole and to the strut joint at the top.IMG1428

The aft strut needs to be measured with the wing temporarily mounted to the aircraft.

With the fuselage upside down on the bench and with the wing in place, level the fuselage with shims under the tail so the strip on the side of the fuselage is parallel to the surface. IMG1432

Use dividers to measure from the lower strut point on the fuselage side (forgot to mention that before that it was located and drilled...my bad) to the mount holes on the wing. IMG1434

Cut and form the aft strut with pins on each end. Glue the aft struts into place. Yes, the struts do have a forward sweep on them that looks crooked compared to the vertical struts. Photos do however confirm this skew on the aircraft. Probably the structure in the aircraft did not line up where it was needed on the wings. Hey, the whole landing gear design is a bit weird too.....
IMG1436  IMG1437

Do not glue the aft struts into place yet as it will make it easier to handle the model further on.

Not only accuracy, but strength. Excellent approach.

Lou

Engine cylinders intro

The aircraft is powered by a Belgian designed 100 hp engine, the "RENARD".

It is a five cylinder radial with some very unusual configurations. Photos on line show several different combinations of valve push rods, exhaust stubs and exhaust collectors.

For this aircraft the most unusual thing is the valve operating push rods and cylinder head. The head has a valve housing for both intake and exhaust in tandem oriented fore and aft on the top. The intake is aft and the exhaust is forward. To operate the valves the push rods are also aligned vertically fore and aft at the front of the cylinder. The rod closest to the cylinder operated the exhaust valve via rocker arm. The intake push rod was forward of the exhaust and because of the inline valves, it operated a split parallel set of rockers on a common shaft to the exhaust valve. Therefore you had the exhaust rocker sitting between the two intake rockers on either side on the same shaft.

Each cylinder had a duel exhaust stack. This engine simply had two short stacks per cylinder like a set of horns. On some engines the exhaust stacks were connected via a collector ring at the front and directed to a long exhaust pipe. 

To duplicate the split rockers would be very difficult at 1:48 scale using wood and wire, so I simplified the cylinders for this model. As well only the cylinders stick out of the rather well streamlined front of the aircraft, so the engine case does not need to be modelled.

The illustration of the simplified cylinder assembly was done on Sketchup to illustrate the completed part. Following will be the pictures and details on construction. Oh yes, the cylinders are only 1/8"x 5/16".

Required materials: 1/8" dowel, 0.020" brass wire. 0.032 brass wire.

Engine cylinder construction - cylinder and exhaust
Cylinder barrel and head

Make a fixture to hold the dowel. I had a piece of 1/2" thick plastic cutting board. Ikea boards are a great source of plastic for projects.  Wood works well too.

Drill a 1/8" hole in the fixture. I then held the fixture in a small bench vise when woking on the part.
Insert the dowel to protrude 1/16' from the fixture. Mark a centreline on the top. IMG1172

Use a razor saw to cut a 1/32 deep notch either side of the line  1/16" down from the top.  A razor blade is the used to split the pieces away from the part leaving the central valve block attached. IMG1174 IMG1175

Drill a 0.032" (1/32") hole through the valve block. This hole will be for the exhaust pipe.

Make the exhaust pipe from.032" brass rod. I cut mine to 3/8" and bent the shallow "V" at the middle using pliers.IMG1171

Insert the wire pipe into the hole. I pulled the dowel down to trap the part in the correct orientation as shown then used CA to glue it in place. IMG1179

Paint the part in the fixure. I used grey head, black barrel and black valve block with black exhaust pipes. IMG1161

Cut the dowel about 1/2" past the side of the fixture to give you a 1" working length. Repeat for the remaining 4 cylinders. Ummm, better make ten to allow for dropping and loss....

You will find it easier to perform each individual step on the batch of parts at the same time.

Engine cylinder construction  - push rods/ rockers

Again, here is a test of you soldering skill. The rods are made from two pieces of 0.020" wire soldered together. The challenge is keeping the parts aligned for soldering and handling such little bits. IMG1142

"L" part = forward (intake) push rod and rocker arms
"I" part = aft (exhaust) push rod
Start with cleaning the wire with fine sandpaper then bend and cut the "L" shape. Each leg is 1/8" long measured on the inside of the bend. Bend a piece of wire 90 degrees then measure and cut the piece to length. The straight "I" rod is cut 1/8" long.
Now the "I" part is soldered to the "L" part with a small parallel gap between the two. The fixture for this is a piece of double sided tape on a sheet of paper! The tape holds the parts into alignment and does not burn up if the heat is applied to the brass. Just don't press hard ...

Putting the parts onto the tape is a fun job. If you try and use tweezers they just seem to shoot the part across the room as you grip them. I found the solution in stick wax jewellers pencils!
These are special wax pencils I bought on Amazon.They are also used in applying false finger nails. They have just the right tack to pick up and hold small parts yet release the part with a little roll of the pencil. If the tip stops working, just resharpen it.

Use the tip to place the"L" part on the tape. Now place the "I" part next to the "L" part inside the leg and with a small gap. The picture shows the "I" part is short, but the "L" part was trimmed later.IMG1150

Cut a small piece of solder. Really small. Too much will wick down between the two parts. IMG1149 Apply a small dab of flux on the joint. Too much and the solder will wick again.

Pick up the tiny solder particle with the pencil and place it on top of the joint IMG1150.

Heat the solder iron and when ready, lightly touch the joint. The heat transfer should be fast and the solder will flow into the joint.

After the part is cool, tune up the joint with sandpaper and paint them as desired.IMG1151

Here is the production run of eight parts on a dime.IMG1160

Cylinder final assembly
Here is the set up I used to handle and assemble the cylinder and push rods. The cylinder is held in the fixture and the push rods are held by tweezers on a base. This allows me to get everything positioned close and then slide the tweezers over to final position. The blue apron is a necessity to catch flying parts....

Once in place a drop of CA is applied. IMG1166 IMG1188 IMG1189 IMG1191

After each cylinder is done, it is cut free from the dowel. Again the fixture holds it for a square cut. IMG1162 IMG1180

The cylinders will be glued into the model later for ease of handling.

Extremely detailed.

Lou

Propeller Carving

The propeller is always a fun thing to carve. It is three dimensional, symmetrical, mirrored shape with a twist and taper. You may have to make a few to get the shape and size right. 

I started with a maple blank about 4 inches long x 1/8 thick, x 1/4 wide. While maple is harder to carve, it will hold the detail nicely. Also give the small size it is strong and the cuts are small.
I drew the dark areas to remove for roughing it out. Looking at the picture of the airplane, it has a scimitar leading edge, ie it is curved like a sword where the training edge is straight. IMG1870

Lou has a tutorial on making a propeller blade. Give it a look at "detailing> propeller blades"

My best advice is to mark the front face and back face with arrows for direction of rotation. The dark areas marked on the front face are the taper of the trailing edge and the leading edge is left thick. The opposite face of the blade is somewhat parallel to the front face therefore the taper is at the leading edge, thinning out the leading edge. Also keep in mind the blades taper from the root to the tip....and twist.  No wonder the Wright brothers took a lot of time and testing to make a propeller! IMG1865

Make a center 1/16" hole at the center for reference and to allow the shaft to be fit. Carving is done with a sharp knife, chisel and sand paper. IMG 1866 IMG1878 IMG1881

Sand the blades smooth always looking for symmetry and thickness. I finished it with a coat of clear nail polish ( basically airplane dope) then painted it mahogany.

Propeller shaft and metal hub

I really wanted the propeller to spin freely. Pictures do show a nice metal hub on the prop so I thought it could be interesting to make that as well. I did not want it to look like the prop was pinned to the model, so a proper shaft is required.

It is not necessary to make a rotating prop, so using a small round toothpick as a prop shaft would work just as well.

So heres my take on making a free rotating prop. I need a shaft, a bushing and a metal hub at the front. Also it should not fall off.

First I used a short piece of .032" brass and dipped the end into a melted blob of solder. IMG2238

I am fortunate to have a small wood lathe to spin the part with. A drill and sanding stick would also work. The lead free solder turns very well and I used a small wood turning tool I made from an 1/8" Allen key. This is shown by the wisp of shaving that was removed. IMG2239 IMG2240 IMG2242

The propeller hole was 1/16" and fit the 1/16" brass tubing perfectly. It is cut a bit longer, approx 1/32", than the thickness of the prop hub. Once CA glued onto the prop hub, clean the brass bushing hole out with a 1/32" drill. Cut another piece of 1/16" brass tube about 1/4" long. Insert the shaft into the prop bushing and slide the 1/4" long bushing over the shaft and leaveing a small gap from the prop bushing. Using pliers, crimp the busing onto the end of the shaft then trim the end off. Holding the end of the shaft and lightly blowing on the prop should set it spinning.IMG 2245 IMG2246

Now the prop is retained with the solder "hub" and is held securely to the model when the shaft end is glued into the nose.

Wheels and tail skid

Again I used the lathe to turn the wheels. I use maple turned to 9/16". The wheel hubs are shaped like two plates joined face to face like a shallow cone. The tire is just a shallow groove on both sides.They were primed and painted white with black tires. IMG1883

Buttons if the right size from the dollar store will work nicely. Just fill in the button center with glazing putty or similar hard filler to get rid of holes or unwanted design.IMG2059

A tail skid was formed from a thin brass strip .025"x1" long x.125" wide folded double 5/32" at one end. The end was soldered to give a thickness to the mounting point of the skid. A .020" hole was drilled at the thick end and the solder reheated to secure a .020" brass pin to mount the skid. The sides were filed to taper and the thin part was bent to give it a spring shape. It was the trimmed to a length of 3/8" Paint it black and install after the model is painted. IMG2058 IMG2237 IMG2257

It was at this point that I noticed I had forgot the stabilizer struts under the tail. I fashioned these from brass tube as described in making and installing the wing struts. ImG 2060

Windshield

The airplane has two small wind shields. They appear to be tinted, so simply making one from card is good and then painted black. I just estimated the size of the windshield width and cut a crescent shape fit. It is about the same size a a large nail clipping...no I did not use one.....

Place them just forward of the cockpit and sloped aft with CA. Do this before installing the wing, its a lot easier.IMG2249

Masking, Painting, Decals
Now is a good time to paint the final color of the model. I chose Model Air Aged White as the overall color with black markings. One of the members on the site, Gordon AKA 'Boomerang" helped me to find a color typical of the era for nonmiltary aircraft.
Clean up the model to get rid of finger oil etc. Touch up the primer as needed. 

I use an airbrush for my modelling. A few thin even coats are applied and then I let it dry at least overnight before masking. This model does not need a lot of masking as the only large second color is the black lettering.

I prefer to cut vinyl stencils to apply trim colors and lettering. I use a Silhouette vinyl cutter to make these masks. The free program associated with the cutter is Silhouette Studio. It has an easy to use interface and I really enjoy making up masks for all ,manor of projects.IMG2079

After creating the markings based on the pictures of the aircraft, I cut them on the machine using stencil vinyl that leaves no residue, leaves sharp edges and (generally) does not pull the paint away. I say generally because a poor paint job may suffer bad patches. Cleaning the model before paint is critical.

The masks are applied to the model using a transfer tape that holds the masking together while you transfer the design. It is essentially low tack soft masking tape. IMG2218 IMG2219 IMG2220 IMG2221 IMG2222

Once the mask is down and pressed with your fingernail, the transfer tape is removed revealing the mask. Additional masking tape is used to protect the rest of the model from overspray. I use cutouts in computer paper to surround the mask when possible.

Paint the markings with a few light coats of black paint.

The wing and fuselage are painted separately. On the fuselage the "-" is on the side strips. I did have a small patch of paint lift removing the mask, but a touchup with a brush worked pretty well.

Decals for the ARPIC logo were made on the same Silhouette Studio program, but they were printed on decal paper and applied as regular water slide decals due to the small size.

The rudder was sprayed with gloss clear and the decals applied IMG2232 IMG2233 IMG2255

After the model is assembled it is given a matt coat of clear that really evens out the look of the paint.

decal application and cockpit panels

Brown paint was added to the instrument panel. the sparse set of dials was represented by a medium tip silver Sharpie marker dot.

Mounting Engine Cylinders

An easy job is to mount the engine cylinders to the model. Set the cylinder in the mounting hole with the pushrods facing forward. The cylinder barrel should press in place and only require a touch of CA to hold them. Make sure to get the center line of the cylinder pointing to the center of the engine inside the cowl (the prop shaft). Make sure they are not tilted fore or aft.IMG2262

Mount the wing

Set the model upside down on the wing with the forward pins in the holes. Put the aft struts in place located with their pins. Check for alignment and level of the wing. This should work out as the forward structure is pretty stiff and the aft struts will hold the angle of the wing.

When it all looks good, apply some CA to the 6 points and allow to harden IMG 2250

Install wheels

I installed short brass 1/16" bushings in the wheel hubs. This was because the wheel hole was too big for the wire axels.

The wheels slide onto the axels and are secured with a drop of CA. Trim the axel flush if it is too long.IMG2234

Install propeller

Make sure the hole for the prop shaft is drilled to 1/16". Insert the prop assembly into the nose. If needed add a small drop of CA on the end to secure it before you put it on. IMG2252
Give it a spin!

FINISHED

That's it! The model is done. Like many of the models built by this group, it is a one of a kind. It is a tribute to my grandson's great-grand father on who was truly an air pioneer in 1930's Belgium!

It has proved to be a bit of a challenge to build not only for the complicated structure but also the sparse information on the airplane with many subtle variations in design. I learned a lot researching, building and writing about the construction process. The nice thing bout this hobby (dare I say craft) is the endless variety of subjects and the great support frommembers of this forum.

Thank you.

Now...whats next?

Fraser

Magnificent results Fraser. Your best model so far. What next?

Lou

Thanks Lou. I'm thinking something with no struts....
Fraser