Monster Fin Guide

Holy sh**, that mustv'e cost a fortune :)

Joel

Holy moley! That's awesome. Must have cost a fortune though.

Aerospace quality machining!

-- Joe Michel NAR 82797 L1

It doubles as a harmonic balancer when he's not building rockets...

David Erbas-White

lotsa free time in the machine shop? or do you have a crew of students for your personal slaves.

I like >: ]

I checked out your hobby page, too. Do you grind your own valves, too? Sweeeet! Do you take requests, too? ;-)

Mark Simpson NAR 71503 Level II God Bless our peacekeepers

Maybe it's the photos, but the slots don't look like they are offset far enough for attaching the fins. What fin thickness is this designed for?

The really old (70s) Estes fin jig was designed this way. The problem with this design is that it ONLY works properly ofr one fin thickness; in the case of the old Estes unit 3/32" fins. Thinner or thicker fins will be offset from where they should be. And the unit wasn't good enough; I could do better by eye than the fin jig did. Not bad for kids, but not for experts.

Now, the Art Rose fin jig was a work of art :-) I still occasionally wish I'd bought one, but they were several hundred $$$ and all hand made.

Bob Kaplow NAR # 18L TRA # "Impeach the TRA BoD" >>> To reply, remove the TRABoD!

Would that be a Bob Fortune? WHere's he been hiding?

Bob Kaplow NAR # 18L TRA # "Impeach the TRA BoD" >>> To reply, remove the TRABoD!

I take requests, but I'm not cheap. I just get these "Tim Taylor" ideas like this huge double throwdown fin guides

Russ Wizinsky

I ground the plates so the offset could be correct. I ground them for the .093" fins. It worked great! I was really concerned with my first high powered rocket flying straight. It worked great, but I found I really enjoy machining more than flying rockets though so I'll be getting out of rockets more into machining. I'll probably be selling all this stuff off, takes up abit of room. I'm also setting up an anodizing system in the garage next to all my machines. Doesn't leave much room for the rockets.

Russ

Russ Wizinsky

I also forgot to mention, that rod in the center is 1.5" or 38mm. The dia. of the whole thing is 11" and weighs in at 52 lbs. (I didn't want my rocket to tip over while drying...)

Russ Russ Wizinsky

What did you machine it out of? Looks like the top of one of those hand crank rotary tables we have on the Bridgeports at work.

I made it out of billit 4340, we had 12" round stock about 6' of it laying around so they didn't mind me making it out of that. It took about an hour just to cut a chunk off with the saw, and another hour to rough it down to where I wanted it on a large lathe. I probably could have done it abit quicker but I didn't want to kill the saw or the tool inserts. It had a pretty rough scale on it when I started so that's why I went down so far, I suppose I could have made it a 11 1/2" but 11 just sounded better. Engineering on the fly kind of thing. The slots I drew up on the cad system.

Thanks so much for all the comments. I will def. look into making stuff for any body who needs something special.

Russ Russ Wizinsky

That was my thought as well. Looks like a lathe face plate.

Bob Kaplow NAR # 18L TRA # "Impeach the TRA BoD" >>> To reply, remove the TRABoD!