Re: Ultimate Endeavor Modification- UPDATE!

That was how we did our first 98mm bore, when we went to a 75mm bore, my hand was too big to get a dremel in and cut out the scrap... so we went to
nesting. You can pick up cheaper hole saws, don't bother with the Bi-Metal expensive ones.
Erik Gates

cheaper
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Necessity is the mother of invention eh? (I don't know who) Improvise, adapt, overcome! (Clint Eastwood as Gunnery Sgt. Thomas Highway) -- Dale Martin NAR 80678 L2 N0JFM

cheaper
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Good point Erik, My knuckles are pretty scratched up just from dremeling the 98mm. No way I could have managed with 75mm. I went back in tonight and put some beefy internal fillets on the fins before I put in the motor mount tube. This would have been pretty difficult as well at 75mm with the three centering rings. After reading your post I took a look at McMasters and found 3 1/8 inch hole saws. These would probably do the trick. If anyone has a source for the cheap(er) hole saws I would appreciate it, I can't seem to find anything less than $12 each for the larger sizes.
The only problem now is I have started looking at 4" aluminum tube stock for making a 98mm motor! That large motor mount beckons! 98mm sugar motor should really take this rocket for a ride!
Stuart Leslie
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76mm
2
motor
the
to
installed.
bother?
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Where is a narrow beam light sabre when you need one...
    Bob Kaplow    NAR # 18L    TRA # "Impeach the TRA BoD"         >>> To reply, remove the TRABoD! <<< Kaplow Klips & Baffle:    http://nira-rocketry.org/LeadingEdge/Phantom4000.pdf www.encompasserve.org/~kaplow_r/ www.nira-rocketry.org www.nar.org
Save Model Rocketry from the HSA! http://www.space-rockets.com/congress.html
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Yah, Harbor Freight has a whole set for $12.99: http://www.harborfreight.com/cpi/ctaf/Displayitem.taf?itemnumber6222. Might only work once or twice before they're used up, but then, how many times are you going to do this before you start building them big to begin with :-)
--tc
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We are now firm believers of making it take the biggest motor possible! Can always adapt down, adapting up requires way to much work. But the cost is much less than building a new booster.
Erik Gates
PS The 1/10th scale Saturn 1B will have 5 6" motor mounts, can always go down in size. but if it ends up to heavy, don't want a garden statue...22' Tall, 26" dia. Should stat build parties next month if all goes well.

to
Bi-Metal
http://www.harborfreight.com/cpi/ctaf/Displayitem.taf?itemnumber6222. Might only

you going to do this before you start building them big to

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