Hi guys

Fate made me make a tree of my last aeroplane.

I am busy rebuilding and have encountered a bit if a problem - no wing!

I have borrowed a wing from someone and plan to cut the foam and build my own. What I am really battling with is how to make a template from the existing wing (wing is joined) to be able to cut the foam.

Search as I may, I cannot seem to find any information

Help would be HUGELY appreciated

Thanks

Jeremy

If it dose not have tubes sticking out you can trace it. If it dose measure the diameter and spacing and cut the pattern in a piece of cardboard slip it on and trace it. If it is a real plane look it up here: http://m-selig.ae.illinois.edu/ads/aircraft.html
For the coordinates of the foil shape you find listed got here: http://m-selig.ae.illinois.edu/ads/coord_database.html

That's a tough one if the 2 wing panels are joined. A bit of work but I think I would first protect the centerline of the existing wing panels with saran wrap or waxed paper. Probably needs to be taped down tightly so its seated tightly against the wing and there are no wrinkles in it. Then I would use self-adhesive foam weatherstripping to outline the root rib. Then, with the wing standing on end, you could use plaster of paris along the weatherstripping, doing the one side first, letting it set fully, and then do the other side with the first side still in place. The fresh plaster on the second side should not stick to cured plaster on first. Then, when the second side is cured, you can removed them, place them back together on a flat surface and trace out the interior shape.

The only thing you'll need to be careful of is that when doing the first side, the plaster does not wrap around the leading edge or trailing edge or you won't be able to remove it in one piece. You can probably use another small piece of the self-adhesive weatherstripping to make a dam at the center of the leading and trailing edges.

you could use something like this http://www.ebay.com/bhp/contour-gauge

Dig through your box of balsa for some scrap. Using CA, build some sort of frame around the wing at the chord of interest, without gluing to the wing, of course. You may allow straight edges of the frame to touch where the airfoil is straight. Use smaller pieces of scrap (maybe 1/8" or 1/4") CA'd to the frame and just touching the wing along the chord at every point. When finished, slide the frame off the wing or cut it off and re-assemble if necessary.

That's how I would go about it.

Since the OP is dealing with a borrowed wing, it seems to be the easiest solution. Templates can be made at the root and tip and transferred to a suitable template material.

Grab a peice of coat hanger wire and bend it until you have the exact curvature for the top and then do the same for the bottom. Combine the two and you have a good representation of the airfoil.

hi
i have a set of foam wings for a gaint shoestring racer 80"wing i would like to do a build up wing how would i make templets for the ribs ,how far apart should the ribs be, what size wood should i use for the main spar ,etc thanks rye

Speed beat me to it. Have done it that way many times. Fast easy and pretty darn accurate..

I've traced many patterns using a compass. it may work for this problem. Anyway FWIW. Use a piece of stiff cardboard or plywood longer than wing chord. Place at the chord point you wish to trace. Make brackets to hold it vertically above the wing. Make sure that distance from cardboard/plywood bottom to center of wing leading edge equals the distance from bottom to the center of the trailing edge. Cardboard/plywood may touch wing at some point depending on compass used. Starting at the leading edge, set the compass so the needle point is at the leading edge center with pencil point just touching the bottom of cardboard/plywood. Insulate the needle point to protect the wing. Note hold needle point vertically under the pencil point.

Now holding compass at 90* to the wing, run the needle point over the wing while pencil marks your pattern material. This will give you the upper camber of the wing. Do the same for the bottom of the wing. Cut along long pencil line and join both patterns and you will have the shape you need.

if compass interferes with wing you can raise pattern material above the wing. Just maintain the equal distance.

This is is a lot easier to do than explain. Hope this is clear and helpful.