Nice job...

Yep been using that trick for awhile myself... I bought some light aluminum angle and cut it in 1 and 2 foot pieces for tube marking purposes and it's a nice backup for that sort of thing, or balsa, or a ruler... usually use clothespins for clamps. Works like a champ.

I don't bother with fin alignment jigs. I prefer four fins, and use an "L" shaped piece of balsa scrap, or a mini-carpenters square (thin steel "L" shaped 90 degree tool I picked up somewhere along the line) and use double glue joints to attach the fins in opposing pairs, one pair at a time, and then put the "L" shaped piece over the end of the rocket like a "V" and using clothespins clamp it to the opposing fins-- holds them perfectly aligned to each other while the glue dries, making them perfectly straight to each other. If the fins are swept back behind the body tube, you can do the same thing using a ruler or flat balsa strip like you did here, going across the aft end of the tube (assuming the motor mount isn't sticking out too far... that's why the "L" is nice...

Later! OL JR

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