- Sep 21, 2017
- Reaction score
There is a whole family of Estes Maxi Brute kits (now OOP) that do just that - balsa cores, with a veneer of ABS plastic or similar.Wow, 3/8" balsa? What's this rocket look like? I can't think when I'd want thicker than 1/8" or maybe 3/16" before switching over to basswood or plywood.
That veneering layer adds a lot of strength to the final part, and balsa core keeps weight down to the minimum, which is good for stability.
BTW, this is similar to the early surfboard construction methods, with balsa (or some other lightweight wood) in the middle, and fiberglass skin on top:
BALSASURFERS - Balsawood Surfboards, Balsawood Blanks, Balsawood Custom Surfboards - FROM BALSASURFERS
Balsasurfers are a company importing Balsawood Surfboards, Balsawood Blanks and Balsawood Custom Surfboards from Equador
Papering by gluing copy-paper to the surface of a balsa fin with TBII strengthens the structure by a LOT!This is second hand knowledge, but everything I've read states that papering with label paper is great for making finishing easier, but it doesn't add any strength to speak of.
At this point, I don't even dare to touch or sand naked balsa fins, since I tend to break off a piece ~25% of the time.
Thus I paper all balsa fins first (copy-paper covered with TBII on both sides, then allowed to dry under pressure to prevent warping).
Then I sand and CA the edges, to harden the areas most likely to sustain impacts, and prevent paper veneer from lifting.
If the fin is really big and I am worried about its strength, I will CA the entire paper veneer surface of the fin. However, this adds a lot more sanding work, and requires weather to cooperate. I've only done this on Estes Shuttle booster (replacement) fins, and Nike-Hercules booster fins.