Jr NOBLER -- wing thickness question

Dear Friends,

I have the Top-Flite kit drawing for the jr Nobler. However, it is not obvious wheather the wing has constant corda/thickness ratio or constant thickness ?

So - before starting to cut the ribs this is very essential information.

My second question is if there is a clever methode to cut/make the ribs as they all are slightly different due to the tapered wing corda ?


Thanks in advance // Ingvar, city of Boraas in Sweden

No, the Jr Nobler's wing tapers in cord AND in thickness from the root to the tip.

About the only way I know of to shape a group of varying wing rips is to create a root and a tip template, stack the rib blanks between them and carve/sand to final shape.

In one of Harry Higley's books he described a similar method - except he was shaping the individual templates for each rib. You'd then take each template and trace out an inboard and outboard rib.

I just finished up a foam wing that was a challenge to shape with the difference in thinkness. I did increase the wing thinkness
by 1/2 on center rib and 1/4 inch on wingtip. I hand shape my foam wings cali-surf-style. Flys AWESOME!

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Great looking plane. What kind of foam do you use and could you describe how you hand carve the wings ? Thanks.

The cleverest way to make them is to go to lazerworks.com and buy the laser cut short kit. It is excellent and good wood. Canopies and decals available too.....

Thanks on the plane, was a gift to my 13 yr. old daughter for her b-day. I use 1 pound virgin foam for my wings.... going to try 2 lb for the leading edge only next time. I use a stucco (EIFS) rasp which has floor sanding paper on it....I think its 40 grit? In the picture you can see my longer 20 inch rasp made from extra shower door over hang. Final sanding is with a t-bar 220 grit. 576 sq. inch Ringmaster wing shown under construction.

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Ingvar,

In addition to the wings, you need to make the fuselage formers using the side and top views as a guide. You will also have to create the elevator and stab. I used the small drawing on the plans to interpolate span and approximate shapes.

Good luck with it.

OK gcb,

I have just simply reduced the form of the root rib shown on the plan to 83 %. This makes the tip cord to correspond to the top wiew plan showing the wing.
To manufacture the leading edge and the trailing edge I might build them from balsa strips instead of some elaborate milling work (even though I have the possibilities to manufacture them from one piece).
The build-up technique is my favorite as it gives me the opportunity to add some spruce in the LE and to make very perfect slots for hinges in the TE.

To make a canopy from a PET bottle is quite simple once the technique is exercised a couple of times.


Cheers!! // Ingvar, city of Boraas in Sweden

Ingvar,

One more thing that came to mind...the fuselage width was set for a steel fin Fox .15, check the engine you are using, you may need to widen the fuselage a bit.

George