Solved How to reinforce the center of an Explorer wing?

[randyrls]

I did the classic THREE LOOPS and fold the wing. I was able to return to the field and land successfully. No damage to the plane. Wing just has crushed foam at the wing joint. I had already used fiber tape for the center joint.

So how to reinforce wing center??

A. Cut open top of wing and insert plywood spar with dihederal angle cut into spar.
B. Use 1/8" (3mm) or 1/4" (6mm) plywood?
C. Make even with top of wing or embed into wing?

Any info on how to make a strong wing appreciated.

 

[Merv]

I reinforced all of my wings with bamboo. I inbeded squires into the foam, 2 in the top & 2 in the bottom layer. The idea is to form an I beam.

Now I can do square loops.

 

[Piotrsko]

You had a compression failure of the foam. Anything that stops that style of failure and spreads the stress around will solve the wing folding there. A piece of anything shoved into the core area, with a coating of glue to make it stick, fabric saturated in resin or glue applied to the top outside skin. Moving the control wire one hole towards the less travel setting.....

 

[ThatsALotOfPlanes]

You could modify the wing to make the middle of the wing flat so you have a section in the middle where you can have a piece of yardstick as reinforcent, but still keep the polyhedral wingtips

 

[FoamyDM]

You had a compression failure of the foam. Anything that stops that style of failure and spreads the stress around will solve the wing folding there. A piece of anything shoved into the core area, with a coating of glue to make it stick, fabric saturated in resin or glue applied to the top outside skin. Moving the control wire one hole towards the less travel setting.....

Exactly... You need a compression member Engauge in enough load to spread the load around I cut slits in the wing's top surface, and use tape from tip to tip on the bottom. This is a Poor representation of a wing loading. Not the Bending moment Chart M is Parabolic. The largest stresses are in the middle 1/8 of the wing. 60"wing reinforce the inner 6-8" or use a 16" L 1/8" dowel. Anything will improve it.