At the last club meeting we were given opaque plastic bags each containing parts for a rocket. Not actual kits, but parts, mostly salvaged from kits. Our job is to put something together with those parts, to replenish our giveaway stock. (You know those eight giveaways I finished up last month? Gone.)
The balsa fins look kind of large for this. Two of them were glued together with a dihedral angle. Don’t ask me. The tube is slotted, and has square holes in it for, I’m guessing, one of Estes’s newfangled plastic launch lugs and some kind of shock cord mount…? The fins have no tabs and were not laser cut. Obviously not the fins that came with the tube originally. The tube seems to be a nonstandard size. The short piece of BT-50 slips into it. Apparently the intent of whoever cut it was that it would serve to adapt the motor mount with 20 to 50 centering rings to fit in the wider tube.
I decided to not use the BT-50 as a single chunk, though; instead I sliced off two narrow rings. A bit sloppily, but that won’t matter. The motor tube was too beat up for use, so I cut a new one and glued up the thrust ring and the motor hook. On one centering ring I cut a notch to provide clearance for the hook, then glued the ring into one of the BT-50 rings. On the other I cut a wedge out completely and glued that into the other BT-50 ring. I slipped that one over the old motor tube to keep it at the right diameter. Then I glued the centering rings on. They’re 1½” apart, just matching the fin slots.