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motors to fit in a NCR phantom or Patriot don't seem to fit.

Hi guys, I acquired a built NCR phantom 4000. it must be a newer once since a red motor retaining ring of plastic seems to be made to fit a molded fin can.

the question is, an Aero_tech single use motor will not fit he MMT. an AT 29/40-120 will just barley fit in and requires a channel lock pliers to pull back out. a doctor rockets RMS 29/180/240 fits in real tight.

was NCR (by estes maybe) rockets a hard fit for AT motors, or was this one somehow shrunk?

wow, I also acquired an NCR Patriot as well, same problem but even a harder fit, humm.....

Art

Reply to
Art Upton
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Yes. The NCR-by-estes tubing and motors were a hair smaller diameter than most other manufacturers' "29mm" size, and the AT single use motors are a little larger in diameter than the reloadable casings.

-dave w

Reply to
David Weinshenker

Yes.

You can peeel a layer of paper from the inside of the motor tube. Use a x-acto knife to start a spiral edge and twist it onto a pair of needlenose pliars. Repeat till proper size achieved.

Jerry

USR BT-11 is about $1.50. Buy a few.

Reply to
Jerry Irvine

If you have not built the rocket yet, then scrap that odd-ball size motor tube and replace it with a standard 29MM motor tube. You'll probably have to tweak the ID of your centering rings with a Dremel to fit the new tube properly.

If the rocket is already built, you'll have to peel the ID of the motor tube. I think Bob Kaplow has some info on how to do that.

-- Joe Michel NAR 82797 L1

Reply to
J.A. Michel

Hey Art,

I too bought a NCR Patriot thinking my Aerotech reloads would work. Nada, you have to buy NCR branded single shots to fit the stock kit.

Nada on that too. I used a 29mm motor tube, sanded out the plastic centering rings provided with the kit to fit and finished off the assembly with a custom motor retention system. Launched perfectly....until the recovery system failed. Opps, my bad...:)

Grant

Reply to
Grant Page

They were deliberately designed that way when Estes made them.

See my .sig article for instructions on how to retrofit fix your model.

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

Reply to
Bob Kaplow

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