2008 Projects

[JeffH]

I've been working on a number of different models in 2008, and will try to post some photos.  First up is a 3/8" = 1' scale (1/32) Grumman Goose.  The model is based on drawings found on a Czech language website.  The fuselage is laminated aspen; wings are from a discarded pallet (note the nail hole-- You get what you pay for!).  Metal struts for the wing floats are from brass rod-- to make them I taped two pieces of suitable diameter brass rod together with bits of tape at the ends, then ran a bead of solder down the interstice between the two rods on both sides, the tape was removed once the soldering started.  I then used a file, sanding sticks and fine steel wool to get rid of the excess solder.  A wire cutter was used to cut the struts to length.

[JeffH]

The attached photo shows the component parts of the Grumman Goose model.  Note metal pins are used to reinforce the wing and tail joins.  The engine cowlings started as blanks from a hole saw which were turned by inserting a bolt through the pilot hole then chucking that in an electric drill which served as a make-shift lathe to finish shaping.

[JeffH]

The next photo shows a 3/8" = 1' ("1/32 Scale") model of a Piper Apache.  The model is based on a drawing found on a French language website.  Also shown is the wood pore-filling medium used on this model-- Fiberglass resin.  The resin creates a tough plastic-like surface which does an excellent job of filling the wood pores. 

Fiberglass resin can be difficult to use though.  The fumes are awful and it won't harden if not mixed properly (or if not enough catalyst is used).  Sometimes the presence of adhesives will also prevent the resin from setting up properly.  When that happens it's best to scrape away the affected area and re-apply the resin using a fresh batch mixed with twice the amount of catalyst.

Almost twenty years ago I used this same type of resin on a couple of models which I never got around to completing.  Those models were dumped in box with other junk and spent the intervening years in a succession of dank basements and unheated garages.  I examined them recently and noticed they still looked the same as the day they were built-- no cracks or signs of deterioration could be seen in spite of the temperature and humidity changes and general neglect they had received.  Based on that experience I decided to try using that product as a wood filler medium again.  An added bonus is the resin seems to add strength to the model as well.

[JeffH]

Next is a Beech 18 also in 3/8" = 1' scale (1/32).  Model is made from aspen with basswood nacelles.  Filler medium is fiberglass resin.  Several coats of resin are applied (with sanding between coats) followed by spray can primer and wet sanding; that's the stage the model was in when the photo was taken. 

After assembling the model I discovered the right wing chord was too small, so built up the leading edge with polyester putty ("Bondo" catalyst activated filler used for automotive body repairs).  It should look okay under a coat of paint.

The model is based on Paul Matt Historical Aviation Album drawings.

[JeffH]

Another project underway in 2008 is this 3/8" = 1' scale (1/32) model of a Cessna T50, also based on Paul Matt Historical Aviation Album photos.

This model is also made primarily from Aspen with fiberglass resin used as wood filler.  The model has been sanded smooth and a final coat of primer applied.

[JeffH]

The Cessna 310R shown below is made from aspen (fuselage, wing tanks, and nacelles), basswood sheet (tail) and wood from an old dresser (wings).  The scale is 3/8" = 1' (1/32).  The model is based on Cessna factory drawings. 

Over the years, Cessna produced some excellent drawings of their aircraft.  Occasionally the drawings show up in books and magazines; these 310R drawings were photocopied from the book Wings of Cessna by Ed Phillips.

Fiberglass resin was used as the wood sealer medium.

[lastvautour]

Each one off your projects turned to be excellent models. You have a gift for this type of work.

Lou

[JeffH]

Thanks for the complement Lou. 

I've started work on a number of models in the past year, and hope to get them all finished eventually.  Next up is an Ercoupe in "1/26th Scale".  The oddball scale was chosen becuase the model is intended as a gift (I usually give my models away) for a relative who has a number of commercially produced solid models in that same strange scale.

Like the other models, the Ercoupe is made primarily of aspen.  Fiberglass resin was used to seal the wood grain.  The model is based on drawings obtained from "Bob's Aircraft Documentation"  (http://www.bobsairdoc.com/3-view.htm) a few years ago.  Text on the drawing indicates it is originally from the July 1950 issue of "Aeromodeller" magazine.

[JeffH]

And last is a 3/8" = 1' scale ("1/32 scale") model DeHavilland Comet racer-- I always liked the looks of those and finally got started on building one.

The model is made up of a variety of wood scraps; I believe the nacelles are basswood, but the rest is a mystery.  The photo was taken early in the filling/sealing stage.  There was some fiberglass resin left over from one of the other models, so I used it up on this plane-- there wasn't enough to cover the model completely though hence the patchy appearance.  As can be seen in the photo, plenty of wood filler was required on this one.

The model is based on drawings found on the Flight magazine archive website (http://www.flightglobal.com/pdfarchive/index.html).  Not a lot of drawings there though.

[Oceaneer99]

Beautiful model!

[Rafael]

Jeff, those all are beautiful. But the Ercoupé and Comet Racer stole my heart. Did you make all that this year? Wow, you're a productive modeler. Also, about your sealing wood with resin, I work with automotive body repair (polyester) resin for my small models. Is this type of resin appropriate for use on wood? and how do you apply it?

Rafa

[JeffH]

Thanks for your complements Rafa.

The Beech 18 and Cessna T50 models were actually started in late 2007 (just cutting out the parts and starting carving), otherwise all the models were made in 2008.

I'm not sure if the fiberglass resin I use is the same as "Polyester Resin"; they may be the same thing.  The can shown in the picture with the Piper Apache model was purchased in the automotive section of the local Walmart store.  Fiberglas resin is also available in hobby shops which specialize in radio controlled models; that stuff is generally much more expensive than the stuff I bought at Walmart though.  I haven't tried using any of the hobby oriented fiberglass resins.  I assume the fiberglass resin I used is compatible with wood; if you look carefully on the can in the photo it shows "metal, wood,..." on the list of materials it can be used with.

Applying the resin directly to the wood is probably the best way to go.  On a couple of the models I tried coating the wood first with Minwax Wood Hardener (that stuff comes in a can with a spout and can be found in the varnish aisle at well stocked home improvement stores).  Applying the wood hardener first may have been a mistake since large patches of the resin didn't cure completely on those models.  It was a mess to scrape off the uncured resin since it forms a really sticky goo when it doesn't cure properly.  I figured the wood hardener would help make the wood water-proof in case I accidently sand down to the wood when wet sanding.

To apply the resin, I add a small quantity of resin to a discarded plastic margerine tub then add about 10 drops or so of catalyst and stir with a popsicle stick-- never stir the resin with the brush you plan to use to apply the resin; unmixed resin will work its way into the bristles and wind up on the model.  The amount of catalyst to add is based on experience.  Too little and the resin won't cure; too much and it will setup too fast and become unusable.  I then use a disposable brush to paint the resin onto the model.  With luck within an hour the resin will be completely cured.  Sometimes the brush can be cleaned off with laquer thinner if the resin hasn't setup yet; otherwise once the resin hardens the brush is ruined.  I seldom manage to get more than one use from a brush.

Usually several coats of resin are needed.  Between coats, I go over the model with 100 grit paper (the package calls this "Medium Grit"-- it's more toward the coarse end of the spectrum).  After the last coat, I switch to finer grades of sandpaper, ending with 320.  After that, I prime the model using rattle can spray paint, then wet sand.  I've found polyester resin is impervious to all brands of primer; some primers attack the polyurethane varnish I've used for wood sealer in the past.

On the Beech 18 model, I used polyester putty to build up the leading edge of the right wing.  The putty I used is also made by Bondo and was purchased from the same place as the Fiberglass resin, and is likewise intended for automotive body repair use.  Body filler putties like that probably aren't ideal for use on wood (for one thing the stuff tends to dry harder than the surrounding wood), but it works for me.  I just mix the stuff according to the directions on the can and apply to the model using a putty knife, followed by lots of sanding once it cures.  I've been using that material on models for years and have never had any problems with it. 

For building up fillets and filling in areas not subject to much stress, I prefer to use one of the latex based wood fillers available-- they are easier to sand and do not produce the fumes polyester putties do. You can see large quantities of that stuff on the Comet racer model around the wing root and cockpit area.

I hope this answered your questions, and thanks for your interest!

Jeff

[JeffH]

The two Ercoupe models were finished just in time to give away as Christmas gifts.  One of the models was intended for a relative who already has a collection of commercially produced solid models; the odball "1/26 Scale" was used so the model would fit in with his existing collection.

[JeffH]

Here's a close up of one of the Ercoupe models.  I used a wood burner to create the panel lines for the cowling.  The cowling fasteners were simulated by pressing a sharpened brass tube into the model surface.  I masked off and airbrushed the "canopy"; I first sprayed dark blue around the borders then filled in the center with the lighter sky-blue color.  I found an Ercoupe logo for the right side on the internet, but had no luck finding one to use for the left side (the logos were "handed").  I ended up making my own logo using the "Inkscape" graphics share-ware program.  The logos were printed on clear water-slide decal paper from Micro Mark and applied to the model.  The propeller was carved from pine; the lengthwise black marks are supposed to represent the laminations (those were made by engraving the prop with an Exacto knife and then rubbing with a black chalk pastel).

Thanks for looking.

[lastvautour]

Outstanding Jeff. The subtle structure just peeking below the wing surface is fantastic. Congratulation on another superb model.

Lou