I recently finished cleaning up a plan for a Sopwith Tripe designed by C.A. Kukuvich and published in the July 1945 issue of Model Airplane News. The plan is actually 0.3 inch larger than the standard 13" W/S because it was drawn to 1/2" to the foot in scale. If the plan is printed out at 97%, then it falls just under 13" W/S. The side view is of his model, as published.
I decided to go with laminated wing tips and rudder outline - 1/32 x 1/16". Forms are thin cardboard with the outer edges sealed with candle wax. Half done now, half yet to go. I cut out the LE and TE parts. Now for all of those ribs!
ian
Watching with interest.
Wow! That was a lot of ribs!. The inner rib ends were upgraded to 1/16 from 1/32", as were the ribs on the upper wing at the dihedral breaks. They will be glued in place after the dihedral is set. Fortunately, I have some detailed pictures of a Sopwith Tripe that I took years ago at a museum in Calgary. I will install the wingtips next after they are sanded in X-section.
My nephew was just at an airshow, and he gave me a picture of a P-51 that he painted. (Yes, I know - no stab. Think of it as a tailless version.)
Waiting with bated breath to see where you put the motor peg ;D
Also following with interest, Ian.
John
I plan on anchoring the motor peg at Former D.
ian
QuoteMy nephew was just at an airshow, and he gave me a picture of a P-51 that he painted. (Yes, I know - no stab. Think of it as a tailless version.)
I recognized it straight away, stab or no stab. Mighty fine painting!
Wings sanded. Top wing center ribs to be added later. I am going to make pockets for the struts. Current weight of the wings is 2.0 grams.
ian
Looks very well made.
I suspect that the original plan was "light on" with ribs. The 3-view in Bruce Robertson's "Sopwith - The Man and His Aircraft" suggests about double the number of full ribs and quite a few riblets.
This was a common feature of early flying scale models, so your model is authentic in being accurate to the original plan, but maybe not up to the standards that currently are being used in making scale models.
Nice work!
I reckon if you are using more than 6 ribs per wing you're not trying hard enough to add lightness! ;D It's always a choice and I always lean toward getting a good flying model. Nice model and look forward to your progress - Tim
Thanks. There is always a limit to how close to scale construction you wish to go. There is a lot of detail in the fuselage and engine that is left out, as well as in the wing. All model construction is a compromise on appearance, weight, expense, and how many years you wish to spend in construction. This is supposed to be fun, not work.
ian
Fuselage sides finished. I altered the plan and fitted the cabane struts into the basic fuselage structure. It makes attachment to the top wing so much easier. Also I made pockets for the wing struts. This is a closeup of how one looks.
ian
Tail feathers roughed out. Slight modifications to the sheet parts to increase the gluing area. Laminated outline added for the rudder.
ian
Tail surfaces trimmed and sanded. I had to add a bit more balsa where the curves were too narrow. Weight 0.4 gram.
ian
Started assembling the fuselage sides. I used a jig on the top of the cabane struts to ensure that they end up parallel to each other, thus fitting the wing more accurately.
ian
Fuselage formers and stringers added. Weight 1.54 grams.
ian
Neat work!
Thanks. Prompted by the other peanut guy, I started with the engine. I started by cutting a 1/4" sq. stick, about 6" in length, out of a larger block of balsa and rounding it with sandpaper (by eye, not a drill). I then sliced overlength pieces and wound them with thick thread. The hub is 1/4" thick. Pieces glued in place. Engine cowl is the next project.
ian
Quote from: pb_guy on Sep 02, 2026, 04:39 AM...started by cutting a 1/4" sq. stick, about 6" in length, out of a larger block of balsa and rounding it with sandpaper...
Or... punch or drill a suitably sized hole in the bottom of an empty (well, duh) soup can, rough shape the stick to size and then gently push it through the hole while rotating it.
I can't sand things to eye to save my life (frighteningly short sighted, spherical distortion from spec lenses, nuff sed?) so this is a way of getting a decently cylindrical dowel without too much waste. Probably slower than your way of doing things though.
Yes, that looks like a way to guarantee accuracy and evenness along the entire length. For best results, it might be helpful to have a form with another hole perhaps 1/32 larger in diameter to pre-form the blank to rough size.
I painted the engine with aluminum acrylic. Final weight 0.83 gm.
ian
Ian,
The build is looking very good so far and I look forward to following further progress
Tim
Thanks Tim. I am hoping to finish everything within the next week.
So, I thought I would do the Rondels today. I don't have any tacky release spray any more, so I tried something I had done before. I started by ironing some thin white tissue. I smeared a piece of bond paper with stick glue and let it almost dry, testing it with another piece of bond paper. Then I pressed my tissue onto the bond paper and ironed the leading edge of the tissue that goes through the printer first. I then printed onto the tissue. Right after this, I peeled off the tissue and mounted it in a cardboard frame. I applied two coats of thinned dope on the top. When dry, I applied one coat of thinned white acrylic paint on the back. I am happy enough with the results. With this method, the colours pop, and the white remains white.
ian
Working on lots of bits. Cowling was made from a piece of 1/16" sheet back and front as well as two pieces of 1/4" glued cross-grain in circles that were hollowed out before gluing together. The motor was moved to the front with a piece of 1/8 " backing. Interior of the cowl was painted black with a sharpie, and the edge of the front piece was painted red before being glued on so as to avoid painting the motor.
ian
Wings and tail surfaces covered and given 2 coats of dope. The bottom surfaces are a pale yellow. I used some $ store plastic toothpicks to hold the pieces above the plastic film while drying. The rudder colours are coloured tissue over white tissue.
ian
I applied the decals today. This shows how well the process works on both light and dark tissue. I also made a Vickers machine gun for it
ian
Those cockades look great!
Thanks. I had to look up the definition of cockade. It means decorations or ornaments.
QuoteA cockade is a knot of ribbons, or other circular- or oval-shaped symbol of distinctive colours which is usually worn on a hat (https://en.wikipedia.org/wiki/Hat) or cap (https://en.wikipedia.org/wiki/Cap). The word cockade derives from the French cocarde, from Old French coquarde, feminine of coquard (vain, arrogant), from coc (cock), of imitative origin. The earliest documented use was in 1709
ian
The top wing was glued in place last night. I am rigging the bottom wing, and when set, I'll move on to the interplane struts and the middle wing. In the meanwhile, I have made the wheels and landing gear struts.
ian
I have been working overtime to make the last few parts and assemble them together. With prop and rubber installed, the final weight is 17.5 grams. The cowl and prop assembly weighs 4.3 grams, and that was necessary to bring the CG to the (estimated) right place. I am taking the model off to our local Fall Fair to show it in the category of "Models built from scratch, not a kit".
ian
Some more pics.
ian
Looking good!
Great model—congratulations!
Peter
Really nice work!
Very well done, hope it Flys as good as it looks.
Thank you for your interest. I want to do a bit more, including making a flying prop before it takes to the air (I hope), but I don't get it back until Sunday afternoon.
They did the judging on the models yesterday. I took a picture of mine when I was dropping off my other entries (marmalade, gluten-free shortbread and fruit/nut bars). There were very few entries in my category. The one outstanding modeller who used to take first place with each of his entries is no longer with us. I have also included a picture of one of his past works at the fair.
Nice build Ian!
Mike
Well done Ian - it looks great.
John
Thank you guys. I really like the look of the finished model. I carved a prop for it - 5 1/4" diameter. The plan called for 4 1/2" diameter, but I didn't think it was sufficient for something over 15 grams. I put a latch on the prop, but I don't really like it that much. I am not sure that it will release easily. It has not flown yet, other than some nice glides. It is rainy here now, so, without an indoor venue, it will have to wait for a while. The final weight with prop and one loop of 1/8" rubber is 18.8 grams.
ian