Just a question on how to secure triangular gussets.

Through trial and error I've discovered several ways whether it be weights or clamps to securely glue one piece of balsa wood to another.

However one activity I haven't yet figured out is how to secure a triangular gusset. Say for instance you have just secured your firewall to the fuselage side, at this point you cut and glue in the triangular stick on the back side of the firewall to ensure it is very well attached to the fuselage side. No matter how I try and pin it clamp it or weigh it down I can never get a perfect bond between both the firewall and the fuselage at the same time without standing there for 30 minutes holding it like a dufus.

I am using five minute epoxy for firewall joints and probond for the other bulkheads.

How do you guys get a perfect bond???

Please note I can't use cyno for allergy reasons.

Thanks,
Grackle

Just use T pins to hold it against the balsa side, that will hold it until dry, although you say you are allergic to CA. have you tried using carpenters glue or whichever you use, on the triangle stock, but leave just about a 1/16 of an inch here and there without glue, and here put a drop of slow Ca., that works very fast and you get no fumes, as long as you apply the drop of Ca. towards the center of the triangle stock.

What is probably happening is that the pointed edge of the triangle stock is 'bottoming out' at the joint of the firewall and the fuse side before you get good side surface contact. Take a razor plane and slightly trim the point of the triangle stock or just sand off the sharp point a little where it goes into the corner and you will have better bond with the sides/firewall. The reason is that there may be glue in the corner of the joint from when you bonded the firewall to the fuse and that will hold the triangle stock out away from where you want it. (If you can visualize what I am talking about.) Same goes for triangular gussets, sometimes your joint isn't a perfect 90 degrees, just clip a little off of the point of the gusset and it will fit better. If you are using epoxy or something like titebond the glues will fill in the slight gap left from trimming the point off.

Ditto what tippie said. I sand off the apex of the triangular stock a little to accomodate the pre-existing glue fillet at the corner of the "L" joint. You can use clamps for the firewall area and elsewhere but it needs some "creative" thinking. For my 4*60 firewall, I cut a small bar out of thick balsa, bevel the ends a little so that it can come into good contact with the middle surfaces of the left and right triangular stocks. Then I use a hobby clamp between that bar and the front side of the firewall. Both triangular stocks were well clamped with no gaps. I also have a variety of adjustable clamps : spring clamps, g-clamps, u-clamps, l-clamps, there's also one with CF rod (can't remember the make), cloth pegs, etc that comes in handy for different applications. Hope this helps.........