Fair enough....but even though I'm a little older than you, I hope to get at least another 20 years or so of use out of it.

__________________
Bernard Cawley
NAR 89040 L1 - Life Member
SAM 0061
AMA 42160
KG7AIE

Bernard,

I don’t have one, but I’ve spent many thousands of $ on Festool woodworking tools from Germany.

One way I rationalize them — they are horribly, ridiculously, absurdly expensive when you use them the first time. After that, they don’t cost any more than lesser tools.

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Lee Reep
NAR 55948

Projects: Semroc Saturn 1B, Ken Foss Designs Mini Satellite Interceptor
In the Paint Shop: Nothing! Too cold!
Launch-Ready: Farside-X, Maxi Honest John, Super Scamp

I think that those springs are constant force springs.
You can buy them on McMaster Carr in many sizes and strengths

I don't know if Art Rose planned it this way or if it's just lucky happenstance, but the shaft which carries the mandrels is a pretty close fit to a MicroMaxx motor tube. Just a touch of blue tape is required to make it a snug fit.

Semroc MMX Goblin getting its last fin on earlier today:

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__________________
Bernard Cawley
NAR 89040 L1 - Life Member
SAM 0061
AMA 42160
KG7AIE

Simple economics . . . If you just dropped $400-$500 on one of these units, you had better USE it, as OFTEN as possible !

Dave F.

Question . . . How much extra would a 24mm and a 29mm Mandrel cost ?

Dave F.

Dave,

24 mm mandrels are $30 and 29 mm are $45.

Dan currently has a couple of the 24's on hand but he would need a couple weeks to crank out a 29 mm.

Steve

Thanks, Gus !

Yup....and ever since I got it I have used it on every build for which that was possible. I have one in the queue where I won't be - that crazy Estes side-by-side cluster Sidekick. It seems like there's been one other in recent times that I didn't use it, but I'm not sure what that was.

__________________
Bernard Cawley
NAR 89040 L1 - Life Member
SAM 0061
AMA 42160
KG7AIE

Okay, I went and bought a Harrison Fin Jig along with the 24mm and 29mm mandrels.

Dan was good to work with and has excellent service.

Shipped on Monday, arrived on Saturday (29mm mandrel will ship this Monday).

Interesting gadget that's for sure.

I guess I had better build a rocket and try it out.

Now that I have one of these devices I am awaiting the appearance of THE Monolith before me which will signal higher rocketry beings (Hard-core NAR competitors? Internats fliers? Elon Musk?) that I have advanced up the rocketry evolutionary scale.

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Bob
S.A.M. # 0014