I am building a SIGLT-40 and one ot the trailing edges is pretty warped. Is there anything I should be doing to straighten it out, or will all the other pieces of the wing hold it straight after it comes off the board?

Thanks!

I've not built the LT-40, although I did buy my grand daughter one for her and her dad to build last year. So, to your question

If it isa piece of sheeting, and an edge has a bow in it, just make a big sanding stick and sand one edge straight. If the edge is straight but warped across the edge, put a piece with a similar warp opposite it on the wing with the warps countering each other. Same goes for spars.

( to ) or ) to ( will straighten out the warps if your build board is straight. Don't let the warps complement each other, always let them fight each other.

A good building tool is a long straight edge. One low cost one can be found at most hardware stores. It is an aluminum threshold., the aluminum piece the fits on the floor under a door. Sort them out carefully, hardware stock gets kicked around a lot. Find one, at least 36" long that is straight. Line of sight along an edge. Most will be bent but you should be able to find at least one straight one. When you get it home, You will want to drill the punched hole from the back. The punched mounting holes will protrude below the edge surface so you need to cut them back to where they are above any wood you lay the edge on. Once you get it prepared, you have a tool to use to cut a straight edge on a sheet of balsa.

The long sanding boards I use are from the frames of some plantation shutters our house had when we bought it. They were very straight wood, probably bass wood. I went to the hardware store and bought some sanding belts, the longest I could find in a couple of the finest grits I could find. A roll of carpet tape and you have a long, very flat sanding board. One 3 or 4" wide belt will last several years. I found a wood workers supply that has assorted grits, up to 400 grit in 1" wide rolls some 20 ft or more in length. A lifetime of sanding sticks for about $15.

These tools, I'm up to about $30 worth now with some good scrap lumber thrown in will help you salvage those warped sheets and balsa planks. The straight edge does double duty as a straight edge for cutting covering later.

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