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Sold Green Monkey Aerospace, 18mm research motor set, never used, $275 OBO

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TRF Supporter
May 7, 2017
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Murray, KY
GMA used to sell a 3-motor set but I also got the 2.75" one so this is one of a very few 4-motor sets. Even the 3-motor ones are awfully hard to find. Time for someone who would like to do itty-bitty research motors to take it off my hands. These are nicely made and anodized, with integral thrust ring. (Apparently the 2.75" motor was anodized in a different batch so it's a lighter shade.)
  • 2.75", 3.75", 5.75", and 7.75" cases.
  • Two plugged forward closures with eyebolts, and one with ejection well.
  • One graphite nozzle (can use AT 18mm phenolic nozzles)
  • Five snap rings, a dozen or so o-rings
  • Two nozzle washers
  • Short piece of plastic tubing for delay grains
  • Casting/liner tube set for each motor
  • Plastic case, and instructions for the 2.75" motor
Just for fun I'll also include a not-GMA 13 mm reloadable motor with threaded closures, and two phenolic nozzles.

Casting/liner sets are always a problem and the ones supplied do not fit well due to old age. So I'm also including two 2' lengths of T5+ tubing for casting tubes, and four 1' lengths of hand-rolled tubing for liners. I'm in the process of rolling these now so it will be a few days before they're completely dry; I'll ship as soon as they are.

I'll ALSO include two 2' lengths of filament-wound fiberglass 18mm tubing, as you may want to test single-use motors before attempting to use the reloadables. AND a foot of 3/4" graphite if you'd like to take a shot at making nozzles.

$275 includes shipping in the continental US. Check, money order, or Paypal.

GMA_01.jpg GMA_02.jpg

GMA_03.jpg GMA_04.jpg



  • GMA_instructions.pdf
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