Salam alikom Abou Abdulah.
very nice project, the problem is that u had used just one layer of the EPS foam sheet and that is not enough to take the load and the stress generated from the flying.
try to built the wing from the beginning and use two sheets of foam this time, and put a carbon fiber rod in between at the center of gravity of the wing then glow the tow piece of foam together. this time you will have strong wing and light one.
regards
well::
actually according to the plan he doesn’t need to do the wing with two sheet of epp foam at least for this project .he just need to enforce wing span wise with bamboo sticks >>>this will do the trick
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