Built a BT-55 upscale of the good ol’ Estes Wizard. Nothing super special, 18mm mount built strong for repeated D10, and D21 flights. Fins are 1/8” basswood. Yea it’s thick, but the large root edge will provide strength, needed with the swept fins that almost endure single fin first contact on landing. Finished weight is right at 3oz so she should move well on the 18mm ‘D’ motors and still turn in an ok small field flight on a B6-2 And I would be remiss not to thank Mark at StickerShock. Awesome work!!!!!