Estes Puma CATO

Discussion in 'Low Power Rocketry (LPR)' started by hermannj, Jul 2, 2018.

  1. Jul 2, 2018 #1

    hermannj

    hermannj

    hermannj

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    Had a rather unusual CATO on Saturday. This is the first I've had (or heard of) on a 13mm motor. I've reported to both http://www.motorcato.org/ and ESTES.
     

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  2. Jul 2, 2018 #2

    mrichhcirm

    mrichhcirm

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    I have witnessed an a10-3 CATO once but never had it happen to me (yet). Trouble with A10s, I think, is that they are small and cheap and tend to rattle around loose in the range box and maybe aren't handled as carefully as they should be...combine that with a fast burn rate to begin with, and I could see how a small propellant crack causes a CATO.
     
  3. Jul 2, 2018 #3

    hermannj

    hermannj

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    Now I'm not sure if I still have motors from the pack. Will the code be same on them? I would hate to build another one of these and have it meet the same fate.
     
  4. Jul 2, 2018 #4

    shreadvector

    shreadvector

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    Rattling does not cause catos. Proven experimentally. See the numerous R&D reports.

    To crack a grain, you must either hit it with a hammer or it must have a manufacturing defect, such as the "Year X" C5 motors. The centerbore tool was defective and produced a sharp edge/stress concentration that crackes after the motors cured. "Cured" = they press the powder damp and then they dry out or "cure" for a while.
     
  5. Jul 2, 2018 #5

    Rex R

    Rex R

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    possibly temperature cycling caused the grain to separate from the casing.
    Rex
     
  6. Jul 3, 2018 #6

    Daddyisabar

    Daddyisabar

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    I have had two 13 mm CATO'S over the years but still more reliable than the E9' s!
     
  7. Jul 4, 2018 #7

    Amsterdam

    Amsterdam

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    Source on numerous R&D reports?

    I’ve had 2 a10-3t catos. I attribute the failures to mishandling. More than rattling around but far less than a blow with a hammer.
     

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