Best way to profile balsa fins for scale rockets?

Hello,

What is the best way to profile balsa fins for scale rockets? I plan on building a Nike-Apache and the booster fins are diamond shaped when looking at the ends.

Thanks in advance,
Brian

 

[Ryan S.]

sandpaper

 

[GL-P]

use some thin balsa (like 1/32) to make spacers and then use some more balsa to laminate over the "frame"

 

[Micromeister]

Don't use Balsa fins! Nike's have alumium plate folded fines with a center or two internal spines. I've built up to BT-80 size nike boosters using the same method in cardstock, cardboard or event 3/64" Plywood. score the card or ply on the inside and fold. CA/epoxy the spine(s), then apply the second side.
If you must use balsa or basswood the best way is to tape the center line and sand with a 12 or longer sanding block in ONE direction only tip to toe or toe to tip until you have removed the amount of material necessary.
Nike fins also taper from tip to root, with is best sanded first then sand the center span fold.

Here's a 2 pic photo of how the cardstock fins are formed, they are more then strong enough for LMR cluster power model flying.

Hope this helps

 

John,

Your post way really helpful. I was thinking a built up fin was the best way to go. A lot less sanding. Where do you get good quality cardstock or cardboard for the fins?


Best regards,
Brian

 

[Stymye]

office supply stores have a good selection, craft stores have some , I like to use thin ply or venier as well on the mid power range stuff. you can score it with a razor knife like cardstock

also depends,how big is the rocket?

 

[Micromeister]

Originally posted by bswan72
John,

Your post way really helpful. I was thinking a built up fin was the best way to go. A lot less sanding. Where do you get good quality cardstock or cardboard for the fins?


Best regards,
Brian

Brian:
The Cardstock seen in the pics are from a File folder and illistration boards I picked up at Gaint food store Most Micheal's have a good selection of different weight stocks. Staples,Art supply stores, and Most Sign Supply shops carry even heavier cardboard stocks called Sho-Card & Railroad board. these can be as thich a 28ply(about 3/32")
Heft isn't really that necessary, My BT-80 model ended up with File folder thickness fins, while some of my smaller models have used printer paper. Once assembled the fins can be CA soaked and sanded into a very stiff and strong unit. Primer and paint only add to the stiffness.
Hope this helps.