David, I would also add a pair of balsa longerons to the formers, tying the formers together. I believe this is the best solution overall, but the ladder brace assembly solution will work okay also.
The inside surface of the fuse is glass/epoxy and probaly traces of mold release, so a thorough sanding and cleaning with alcohol is best. Definitely use Polyurethane glue that Peter found. It will foam up to fill any imperfections in the joints.
Small pieces of the broken fuse will allow easy separation of the glass and foam wall. The epoxy adheres well to the foam, but once the foam is compromised, the foam becomes granular and the bond is lost. Best to remove the inside skin completely and start over. I know it is hard to do.
regards
mattK
ORIGINAL: David Gibbs
If I continue down my truly conservative road to building Impact number 2, I am inclined to follow the suggestion in another thread of putting three oval formers in the fuz (I think it was Matt's suggestion) to ensure the integrity of the oval shape stays in place, as well as the ladder. This tackles three (likely very minor) risks that may exist with the ladder only if whatever is causing our issues puts the fuz at that point in tension (ie, sides pulling away from the ladder). I would rather have something in compression on the vertical axis stopping the deformation in parallel.
- The first is that I am not 100% confident I can get a really good contact/bond to the inner surface of the composite all the way down the fuz on both sides (and if I do it may weigh more than the ladder!);
- The second is I am not sure of the best glue to use -- I have been sanding and cleaning the inner surface, and using epoxy, but it clearly isn't a full strength bond to whatever the inner surface of the composite is -- any ideas on better glues to use (I am not familiar with some of the ones mentioned above)?
- The third is that when I do get a good bond, on the samples I have been playing with on the broken fuz, I can pull the inner layer off the composite.
You may call me paranoid . . .