Source for fin jig for 38mm

Anyone know where to find a pair of fin jigs for a 38mm 4 fin design? I have been using the fin guides that Mac Performance sells, but they do not show anything smaller than 54mm.

If anyone can make a set, that would work, also. 4 fins, fin thickness .100"

I have a set of these in a few sizes that I like.



https://www.smtdesigns.com/store/bt6038mm-fin-holder

payloadbay.com has a fin jig generator. Enter your dimensions, print it out (make sure it's 100% size when printing, slap it on a foam board, and you're all set!

Nytrunner said:

payloadbay.com has a fin jig generator. Enter your dimensions, print it out (make sure it's 100% size when printing, slap it on a foam board, and you're all set!

Click to expand...

That's better than nothing, but foam cut-outs only control for fin's vertical orientation w.r.t. the airframe.
Ideally, you want something that fixes the longitudinal alignment as well.

That's where a fin-jig like this one comes in handy (good for tubes from 13mm to 2.6"):
https://www.erockets.biz/semroc-joes-fin-jig-ii-sem-fj-2/

I am looking for a set of plywood fin jigs. I can scribe a line on the axis of the tube, and tack on one fin accurately. The other 3 glue on easily. I would rather not have to make these jigs, if I can buy them somewhere.

At one time Black Aero made some but they didn't seem to catch on, I think maybe because they didn't have a flat spot. He probably still has the files, maybe he can modify them to have a flat side more like MAC's. They're 3d printed, not plywood. I have a set of 38mm 3 fin and they worked better than any foam board I've ever cut out.

https://www.blackaero.com

Check Wildman-they sell fin jigs, I believe made out of fiber glass

Chris_H said:

Anyone know where to find a pair of fin jigs for a 38mm 4 fin design? I have been using the fin guides that Mac Performance sells, but they do not show anything smaller than 54mm.

If anyone can make a set, that would work, also. 4 fins, fin thickness .100"

Click to expand...

Do you have access to a 3D Printer? Super easy design to print out. I have a OpenSCAD script file that I got from here somewhere that lets you generate any size you need. I'm printing a 4"/4 fin guide right now.

From the Wildman web sight under his Black Hawk 38 mm kit, you'll see G10 fin guides. If interested, call them Monday and see if they'll CNC the 4 fin guide you need.

I just checked the Wildman site. I love Wildman! Unfortunately, the only fin jigs they have listed are 3 fin, not 4 fin. Maybe they will make them. Thanks for the tip.

My Wildman Mach 2 came with a 4 fin jig. It is 54 mm, but it does show he makes 4 fin jigs.

check WM he has them on his website

FMarvinS said:

Check Wildman-they sell fin jigs, I believe made out of fiber glass

Click to expand...

Yep.