meat tray wing construction ?

[Grizzly Greg]

Has anyone used meat tray foam to make wing ribs? will it work? will it be heavier than balsa? what spar material would you use? Say for a 30" to 36"ws scale type.Any and all input would be appreciated.
Thanks Grizz.

[jimwalker]

These are just my opinions since I've never used depron to make ribs, but it sounds possible depending on the structure. If you are that concerned with weight, use carbon fiber rods for spars. I'm not sure if the depron would hold up to much tension when you cover it though, from my experience with solid depron flying surfaces, it will probably fold up near the trailing edge where the airfoil shape will make the depron ribs thin. I've tried using thin white glue and tissue to laminate depron and thus increase its shear strength. It works great for strengthening solid flying surfaces, but I don't know if it would be enough for your proposed ribs. Also, would it still be a significant weight savings? Do you want to spend the time "messing" with it? If I tried it, I guess I would laminate a peice of depron on both sides and then cut out my ribs after the glue dried. Then weigh them as compared to contest balsa ribs. If they were significantly lighter, then test for shear strength in a covered air frame. I hope this helps and let us know what you discover....

Happy Flying

[Grizzly Greg]

Howdy Jim, its more a question of buget, I'm not trying to whine,but I have more time than $,so "messing with it" is a viable option.I was also thinkin if the depron could be used and be comparable to balsa in weight,not neccessarily lighter. Maybe a multiple spar system like the stick models,with a leading and trailing edge,covered with "reynolds" wrap...something along those lines...anyway I'll give it a try and see what happens.
Thanks,grizz.