This page is dedicated to suggestions from other builders. Suggestions will be added as we receive and edit. Please email suggestions or questions to tbrox@cox.net

Home

Matt Kebabjian

I like what you have done. My methods are quite similar. About the only differences I see are in the false rib as support for the socket end, socket installation, aileron capping and wing TE, and carbon ribbon "spars".
 
I do not use false ribs in my wings but rather I cut the slot in the foam centered on the tube socket,  to accept a slip fitting 1/8" medium balsa sub spar that extends about 3" past the end of the socket. During the skinning, an extra layer of 2" cloth 4" round, is added top and bottom, covering the end of the socket and subspar
 
I install the sockets and spars to both panels at the bare foam stage, and build in the dihedral and panel alignment on the foam first. I leave that assembly alone with tube spar installed to cure. The new carbon/glass sockets for carbon tube spars tend to be flimsy, so by actually inserting the tube, it serves to mold the socket perfectly as the Pro-Bond cures
 
I use no carbon ribbon for spars. I generally do not use carbon veil on thicker wings about 10% and thicker, but do use the material on thinner sections. Have also used 1K tow bias applied. I prefer the carbon tow over veil for torsional rigidity.
 
The aileron caps are applied in an identical manner except the cap which forms the wing TE is cut about 3 1/2 to 4" longer than the aileron LE, and inserted in a precut slot. It eliminates the natural stress riser at the wing TE. If the servo cut out vs socket end isn't well thought out, the stress riser will break the bottom sheeting from the TE to the servo cut out. It happened to one of my wings 15 years ago so I came up with the alternate method and have used it ever since.
 
Oh yeah, almost forgot. You should try vacuum bagging you wings. If you do, the simplest stuff to use on LE and TE to make sure the vacuum works here, is plain paper towels. Wrap these around the LE and TE and tape them down. The simplest sealing medium I have found is plain plumber's putty. Not only does it do the job even in cold weather (okay 40 degrees in Fla is cold), but it is reusable and the bag isn't ruined. I use only 5-7 inches mercury vacuum or about 1/5 atm. Well you know what that equates to for a 500 sq in wing. Except with vacuum, you are applying it over both surfaces, so it's double the load. The foam we typically use is 1 lb density and it has guts enough to withstand about 12 inches mercury before beginning to crush.
 
Glad you took the time to do this for the newbies. I was going do it, but you saved me a bunch of work. If you think my methods could add some value, by all means add  them to your descriptions; that's the reason I sent them.
 
Over all a very nice job
 
Matt K
 
PS- I am working on methods for balsa-less light weight composite skinning. We'll see where it takes me