Hope you are talking about the joints between the ribs and spars.  I make mine out of what ever scrap balsa I have laying around.  They look like the old 90-45 triangles we used in drafting class.  Have the grain running from one surface to the other, not parallel.  If you were here we could have had a couple dozen cut well before now.

Here's the gussets on my PDQ Lion Tamer.
I noticed when I completed the wing (uncovered), the solid L/E's were far stiffer than the wimpy 1/4"x1/2" spars + the 3/16" tapered T/E. The wing wanted to washout when I held it by the tips and gently bounced it toward the ground.
I just didn't like the shear point at the spar/ sheeted center-section so I added 1/8" tapered spar gussets just outbd of it. This helped ALOT by distributing the stress across the bay. A tight Monocote job should do the rest.

Stupid Computer...trying to post more than 1 pic in a post. 

Here's a close-up.

Doug, The limit for attachments is 1,000kb, and your pictures total more than that. They could easily be cropped/resized/compressed to 100kb...so you could post 10 of them. There are several useful and simple to use programs to do this. There's a post on the Administration Forum about posting pictures that covers it well. Rudy Taube was the originator of the thread, so that would make it easier to find.

Have you used the MACS Muffler before? I have used it on an OS .46LA quite a bit. I expect yours is a .25? The key to these is to prop it so that it'll hit the right rpm (it's a tuned pipe) and be launched about 1,000 rpm under peaked rpm. For the .46, that's around 10,000/10,500 launch...and the 11.5 x 4 APC is about perfect. For the .25, I'd expect more rpm and start with the 9-4 APC or Graupner...but don't fail to experiment with props!  Steve

doug. what is the red and white filler you used?

I have used superfil and spot putty never caulking. the red putty tends to bleed. they also sell putty in white blue and green. thanks for the info.