BT55 3 Fin Model Rocket Alignment Jig

thingiverse

This is an assembly guide for creating adjustable fins on a model rocket. This is an updated version of my standard 4-fin jig design. To be honest, I have not put this to the test as most of my BT55 sized rockets are scale versions of missiles, typically sporting four fins. There are numerous alignment jigs available. What sets this one apart is its use of meandering printed springs to secure both the jig and the fins in place. This innovative design allows for a considerable range of variation in body tube diameter as well as fin thickness. The recommended fin material is 3/32 balsa or ply, but it will also accommodate slightly thicker or thinner fins if you're a bit heavy-handed with your sanding tool or if you choose to fiberglass or paper your fins.