AT DMS L 1000??

Discussion in 'Propulsion' started by JDcluster, Jul 11, 2019.

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  1. Jul 11, 2019 #1

    JDcluster

    JDcluster

    JDcluster

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    I picked up an L 1000 a few weeks ago. Are the grains suppose to rattle?
    My first 54 mm DMS, just not sure if they are suppose to do that or not???
     
  2. Jul 11, 2019 #2

    burkefj

    burkefj

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    I believe so my j450 in k535 so I bought do you have the grains move back and forth but you do want to double-check the date code for that motor and make sure it's not susceptible to the case winding issue that caused them to fail
     
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  3. Jul 11, 2019 #3

    TimothyG

    TimothyG

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    Grains sliding forward and aft is fairly common in Aerotech DMS motors. I freaked out first time I noticed it but haven’t thought of it since my dealer and Aerotech rep both okayed it. Side to side rattling I may concern myself about but not endplay.
     
  4. Jul 11, 2019 #4

    cerving

    cerving

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    I think AT pretty much got rid of the case winding issue, I had two of them fail a couple of years ago but the one that I few out at NSL last month worked great. They've also worked around the thrust ring issue that they had with early DMS motors, too. Unless your motor is dated pre-2017, you probably won't have any issues.
     
  5. Jul 11, 2019 #5

    Cameron Anderson

    Cameron Anderson

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    Yes they rattle. Totally fine. I've flown one, they fly great. My K850 DMS rattled too.
     
  6. Jul 11, 2019 #6

    JDcluster

    JDcluster

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    I'm aware of the date code case winding issues.
    040919 on the packaging.
    Picked up from Wildman on 06/22/19
     
  7. Jul 12, 2019 #7

    manixFan

    manixFan

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    Grain rattling seems to go back a long way. I have flown dozens of old Ellis Mountain single use motors (mostly H101s) and many of them have rattled. While it's pretty easy to precisely cut a liner, it seems to be much harder to cut grains with the same precision, especially in bulk. I suppose when they assemble the motors they could use o-rings to keep the grains from rattling. On occasion I've had grains rattle in motors I've assembled and all have flown with no ill effects.

    But still, it is a bit disconcerting.


    Tony
     
  8. Jul 12, 2019 #8

    JDcluster

    JDcluster

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    I just wasn't expecting it to do this. On my 54 mm x 2550 loads, I glue the grains to the liner.
     
  9. Jul 12, 2019 #9

    Cameron Anderson

    Cameron Anderson

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    It is weird, it's almost like it's missing a grain, but trust me, it'll stay together. I wish my regular field had a higher waiver so I could fly it more.
     

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