Further progress today. But first, a learning point:
The design has three sets of CRs on the MMT (four if you include the one that centres the tailcone).
The forward CR is doubled to increase strength for the eye bolt for shock cord attachment.
There’s a CR that sandwiches the TTW fins fwd, and one aft.
As you saw from earlier pictures, the fwd and fin fwd CRs were glued to the MMT tube.
Plan is for the one aft of fins to be put in after internal fillets are done, then the tailcone can be glued last.
Tailcone is being used to keep the MMT level while gluing into the airframe fin can.
So the plan was to do as I’ve done many times before: glue ring above fin slots for the fin fwd CR, half insert the MMT from the front, tip the MMT, apply the glue in a ring for the fwd CR, straighten, insert all the way, then fillet where I can from the outside and clean up any drips or over runs.
Well, it turns out that I’ve managed to PERFECTLY align the two sets of fwd CR’s such that I can’t get to the spot for the fwd CR glue, without dragging the fwd fin CR through it.
So a learning lesson there...
Solution? Best I could come up with was to push it in 8mm too far (so the fin CR is inside the fin slot area) ring the fwd CR glue with a stick, then inject some 15min epoxy onto the front of the fin fwd CR, and then push the MMT forward and then roll the can to try to dribble as much of the injected epoxy into some kind of fillet.
So there’s the fin can upright now and curing...
Incidentally, I did remember to loctite and tighten the fin can shock cord before I glued it all in.