Fin alignment jig

Welp,

The winter time projects continue. This time, I finally got around to making the fin alignment / setting jig that I've been threatening myself to build. :wink:

It's a combination of ideas I've seen floating around on this forum, Ye Old Rocketry Forum, and general Google searches. The morphing of all those ideas has resulted in this jig. I'm still working on it...have to make notches in the other l brackets to make room for the wing nut, and I decided to stop and test how the other parts work out.

The brackets can be moved for 3 fin or 4 fin configurations. They are held in place by a carriage bolt.

Second pic shows how it is used to align and hold a fin to glue or epoxy in place. It is a rejected fin from a previous project, BTW...

Hopefully someone can use this idea to morph into their own project!



Don't mind the messy workbench...I've been busy the past several weeks.

-C

Pretty cool, I like it! I have some of the pieces and parts to build something similar, but haven't gotten around to it yet.

Couple questions, though. As far as I can tell from your design, it is for only one fin thickness, right? Thats part of what is holding up building mine, as I use anywhere from 1/16" to 1/8" fins (so far), and can't really figure out how to have the guides (very accurately) adjustable. I suppose different sets of holes to bolt the fence to could work.

I wish I had a drill-press, I am tempted to have something like this jig CNC machined out of aluminum, but that would be $$$, but probably worth it.

I've seen the aluminum fin jigs online, but I think I could have one made for less. If I made it big enough, maybe up to a 4" BT size, it would last a loong time.

McKailas Dad said:

Pretty cool, I like it! I have some of the pieces and parts to build something similar, but haven't gotten around to it yet.

Couple questions, though. As far as I can tell from your design, it is for only one fin thickness, right? Thats part of what is holding up building mine, as I use anywhere from 1/16" to 1/8" fins (so far), and can't really figure out how to have the guides (very accurately) adjustable. I suppose different sets of holes to bolt the fence to could work.

I wish I had a drill-press, I am tempted to have something like this jig CNC machined out of aluminum, but that would be $$$, but probably worth it.

I've seen the aluminum fin jigs online, but I think I could have one made for less. If I made it big enough, maybe up to a 4" BT size, it would last a loong time.

Click to expand...

Thanks!

Yes.

As of right now, it's set up for one fin thickness.

One quick thought for a design modification would be to maybe drill alternate holes in the L brackets themselves, or have long slots in the L brackets to manually offset to compensate for different fin thicknesses.

I love this group! Post an idea, and get suggestions back to improve on the idea, or have questions asked that sparks improvements!

:handshake:

-C

This is the one I'm wanting to copy, but modify...this one seems awkward to adjust for different fin thicknesses, add shims?

I'm thinking instead of a 'fence', to have precision holes, to which aluminum rods (~1/2" dia?) would bolt into the base from the bottom. Maybe only one set of holes, but different diameter rods to compensate for fin thickness. The rods could have a machined shoulder to ensure they are flat to the base. Hmmm....