[tallone66]

Going to throw this out here for the folks who build large scale.

I currently have a unionville 1/4 scale Beaver. I do not like the wing design or construction, Each wing panel weighs a ton.

I have no problem making my line drawings for the wing, have a solid grasp on design and construction techniques as well. The one are that i need help with is main spar size.
I will be building a D Tube wing, it will still be 2 piece, using the strut to carry most of the flight loads, I do want to impiment a wing tube to facilitate field assembly and carry some load as well. All but load bearing ribs will be balsa, shear webbing will be incorperated. Just need help with size of main spar.
Was thinking of a laminated design ( as per 1/3 spacewalker), this would enable tapering out at the tips. Most likely be using either spruce or poplar for the spars.

Any help from anyone would be appreciated.
Thanks
Derrick

[CdnFlyer]

Have you considered foam core, sheeted with balsa. This proves to be very strong yet light weight. Channels can be routed out before sheeting for any servo extension leads, cabling for lights, wing tube, etc. Epoxy interal supports for strut attachement points also proves to be extremely strong for load bearing.

I have used sheeted foam cores in the past, and really, really hard to snap a wing.

[Struts1]

You took word out of my mouth, i was going to suggest foamcore route also but waiting to see his pics first before this option.

[mrrandyman]

Give the folks a call here at the following site. He might be able to give you some ideas.
https://mraerodesign.securicom.ca/en...pg&ProduitID=2

[tallone66]

Thanks for the replies guy's. No, i did not consider foam wings. I am not set up to cut the plugs to make the panels, and sheeting in a 64 inch wing panel would likely be a PITA.
I will give the folks at Areodesign a call, see what they suggest. Trevor B gave me a few suggestions that look like they would work well also.
I appreciate the sugestions, keep em coming.

Cheers
Derrick

[Struts1]

You can apply fiberglass with epoxy resin directly on the foam. For wings this big ill go with 4oz or 6oz cloth in double layer and use pealply to absorb access resin. I can cut cores for you n shipem to u.
I can also hollow the foamcores to cut down weight a bit plus make slots or channels for main wing spars also.

Some food for thought....

[kip51035]

PM sent

[tallone66]

Thanks all. Kip, Will reply to pm in a bit, back on night shift.