Tutorial Novice - Curtiss P-40E/Tomahawk Mk I

[lastvautour]

Next a bit of work on the main plane. My blank dimensions are 6.5mm X 24mm x 19mm. Cut out the top of the wing template.

For version one - do not flatten out the dihedral for this version.Version one has been moved to my P-40B build on my board


For version two - start by marking the shape of the wing on the blank followed by pasting the front shape to the edge. Note the dihedral has been cut in the center and the top of the image lined up with the top edge of the blank.  Ensure the drawn template image lines up with the front image. This is the easiest of the two.

The difference is the first version is built flat, cut in the center and the dihedral will be set once the wing is shaped. The second version has the dihedral built in. Both are viable and each has its own problems. More on that latter.

Lou

[lastvautour]

Wing version two: The second version can start being the thickness of the wing shown in the drawing. Once rough shaped the flat side of the wing will now be the bottom of the wing.  Finish shaping the outline of the wing. Remember the flat side is now the bottom of the wing.

Lou

[lastvautour]

Fine shaping the wing can be done with whatever blade you prefer. I use a chisel. On occasion, I use clamps to hold the piece. Note that you must remove the excess wood slowly of gouging like the one in my stab will occur. Use a large or small blade. When removing narrow strips take greater care as resistance is lower and the tendency to remove too much is ever present. Use a ruler or other straight edge to check your progress. Contouring the airfoil shape will be done later.

Lou

[lastvautour]

Contour shaping of the wings will be done next.  First mark the location of the guns by overlaying the wing over the drawings. Trace a line approx. 1.5mm along the bottom of the wing. Intersect those with vertical lines. I use a push pin to mark the locations and then use a 1/16"  drill bit. These are available at any hardware store and is usually the smallest bit you can get before going to a specialty shop; This is also the nominal diameter of round toothpicks. I use a nail clipper to rough cut the guns. Do not glue them yet.

Note that last photo show damage between the starboard guns. That will be fixed with putty once the airfoil is contoured.

[lastvautour]

This may be good time to get some sanding sticks. I use paint stirring sticks available for free at my local hardware store. Glue two different grit sandpaper at one end and another two at the other end if you so wish.

Lou

[lastvautour]

Creating the airfoil shape take time and several steps. First is marking the leading edge of the wing at the 9MM-18mm at the center point and 7mm and 3.5mm at the tips. Run a line on the face of the wing 2mm from the bottom. I forgot to take a photo of this process, however you can still see the lines in the shaping photo.

Starting at the center point, remove the wood between the first line and the line on the face.

Next draw a line spitting the surface you have just revealed and remove the wood between it and the second line.

Sand that to a smooth curve.

The tip is is flattened slightly as shown in the drawings. You can carefully cur it/sand it to shape.

Lou

[lastvautour]

Once the leading edge is sanded smooth use a straight edge and mark vertical parallel lines. Tilting the wing gives a view of the contour.

Lou

[lastvautour]

Trace lines at the 10mm and 5mm point as shown. Trace a line on the face of the trailing edge approx. 1mm from the bottom of the wing. Carefully do the same as the leading edge of the wing slowly carving the airfoil shape.

Lou

[lastvautour]

Using the template for the wing airfoil shape. This one is pretty close on the first try. Final shaping was done with the coarse sanding stick. Next is marking the bottom area and shaping using a sanding stick as the amount to remove is small.

Lou

[lastvautour]

Draw vertical lines on the wing and tilt to see the shape of the wing. Note I neglected to take a picture of this so they were added after the picture was taken.  The first attempt with the airfoil template was pretty close so a bit more sanding made it even better.

Lou

[lastvautour]

CAUTION

Do not try to catch a knife in mid air.

OUCH

Lou

[Gearup]

I was wondering what the random red lines were for....uh never mind 😯
I like the idea of using the fingernail clippers for close cuts such as you did with the gun barrels so close together.
Fraser

[lastvautour]

Once satisfied with the shape of the wing will set the dihedral by cutting the wing in half. The cut must be perpendicular to the wings span. To do so otherwise with skew the shape pf the wing. It can be cut with a hundred strokes of a shape blade or, in my case an Exacto saw. The object being that it needs to be a narrow cut.

Lou

[lastvautour]

Note the inverted V. Ensure the wing held is parallel to the sandpaper. Sand down until the joint is flush when using the dihedral gauge. I doubled the height of the gauge to enable one wing to lay flat. I used super gel glue and let that set. Once dry I ran liquid super glue along the joint.

Lou

[lastvautour]

Using the airfoil template, line up the front of the template to the bottom of the fuselage and not the cooler. Once traced, repeat on the other side. I used my bandsaw to do cut short of the template line. Using a paring knife, I twist the small pieces out.

Lou