vendors of HPR custom fins?

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TWRackers

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Okay, it's been 1½ years since I asked this question on TRF 1.0, so I suspect the answers may be different this time around.

Which vendors out there can cut custom fins for HPR projects? I'm thinking of something ¼ inch thick, with a fin root length around 15 inches and a fin chord (root to tip) around 5 inches, with a 12-inch TTW tab suitable for a 75mm MMT inside a 6-inch airframe (about 1.56 inches). And I would need four such fins. Basically, they'd be clones of the fins on my Level 3 rocket (which sadly still has not been located after its maiden flight at Red Glare VII).

The original fins were cut by me when I had access to a band saw, which is no longer the case.

(Moderators: if you think this post is better suited to the Vendors section, please move it over there.)
 
Ken Allen has made them for me...not personally but as an agent. I thought Giant Leap used to make them.
 
Wildman G-10 or wood
PML G-10 [don't know about wood]
LOC G-10 or wood
Giant Leap G-10
Hawk Mountain. G-10
Binder Design G-10 or wood

All can do it......... some maintain a library of popular shapes, upscale or down.
 
The original fins were cut by me when I had access to a band saw, which is no longer the case.

If you get the wood, you can use my tools. I have a band saw, but it needs a new blade. Normally I cut all my fins with a jig saw.
Here is the place in Rockville where I get some things. By the way, I believe they'll cut something for you for a small fee.
https://www.woodcraft.com/Family/2004113/2004113.aspx
 
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Y'know, I really wish I could duplicate the way I made the set of fins I actually used on my rocket. When the 5-ply aircraft birch fins I originally cut warped after being cut, I made new fin stock by using four 1/8" thick (3 mm actually) sheets of Midwest Products plywood, pairing them up, then epoxying them together with West Systems 205 and two layers of 3 oz fiberglass cloth in between, and allowing the two stacks to cure for 24 hours under vacuum against a large flat aluminum plate. So I ended up with 11-ply fin stock (including the center layer) that was just slightly thinner than 1/4", but was rigid and FLAT. The fins I cut from those two sheets never showed the slightest tendency to warp. Sure wish I still had access to the equipment to accomplish that. (sigh)
 
You don't need the fancy vacuum pump etc.

A couple of bucks for some 2 ft tile from HD or Lowes etc. lay up your fin stock as before on one tile, place another on top, a couple of blocks, sand bags, water filled jugs, etc on top of that.....you can get pretty darn close results for 5-7 [0 if you still have the aluminum plate] bucks on your fin stock.
May not be as fancy or pretty , but it works!
Then get it cut the way you want.

Just use your old rocket ingenuity!
 
Y'know, I really wish I could duplicate the way I made the set of fins I actually used on my rocket. When the 5-ply aircraft birch fins I originally cut warped after being cut, I made new fin stock by using four 1/8" thick (3 mm actually) sheets of Midwest Products plywood, pairing them up, then epoxying them together with West Systems 205 and two layers of 3 oz fiberglass cloth in between, and allowing the two stacks to cure for 24 hours under vacuum against a large flat aluminum plate. So I ended up with 11-ply fin stock (including the center layer) that was just slightly thinner than 1/4", but was rigid and FLAT. The fins I cut from those two sheets never showed the slightest tendency to warp. Sure wish I still had access to the equipment to accomplish that. (sigh)

You do not even need to go through all that. I have used 1/4" plywood with a layer of 8 oz glass on each side. I have a old end table with a flat surface. I place a layer of 5mil mylar on each side of the plywood after glassing the plywood. Then place it on the end table and stack a bunch of books on top for a day or two. After that I trace the pattern onto the sheet and cut out my fins. No warp and are very strong.
 
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