RMS vs DMS

Discussion in 'Propulsion' started by Nathaniel_, Jun 12, 2019.

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  1. Jun 12, 2019 #1

    Nathaniel_

    Nathaniel_

    Nathaniel_

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    I've been looking for a motor for my l1 cert and I've been told that an RMS is the way to go. But after searching, I see only a 5$ difference between a ceseroni reload and a DMS. I'm not really sure which one to pick, or if I should try to find an areotech 38mm casing, which I can't seem to find closures for anywhere.
     
  2. Jun 12, 2019 #2

    Eric

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    For your L1 cert, a DMS motor keeps things simple. The H 115 DM is my favorite.
     
  3. Jun 12, 2019 #3

    mbeels

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    I think that DMS is a very good option for an L1 cert motor. It takes a few more variables out of the equation. The ceseroni 38mm are also super simple, I used one for my L1 and it was as simple as adjusting the delay and screwing into the case. I'd go with whichever is easier to obtain. Do you have a vendor at your launch site?
     
  4. Jun 12, 2019 #4

    WhiskyTangoFoxtrot

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    DMS all the way,baby
     
  5. Jun 12, 2019 #5

    ThirstyBarbarian

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    DMS and CTI are equally simple, with the main difference being you drop the CTI reload into a case and screw it shut. They are both very easy compared to building an RMS motor, and that’s why these are all I use — I like it simple and don’t like “building” motors, so I don’t even own any RMS hardware.

    With CTI, you would need to buy the case as well as the motor, but sometimes there is a cert special that gives you a discount or even a free case when you buy the motor for your cert flight. I used a DMS H115DM for my cert flight, which was super easy and a great flight. Later I found out I could have got a free CTI case if I had gone with CTI. For L2, I got my 5 grain 38mm case for free. I’m not sure if there are any cert specials currently, but it’s worth checking. Good luck on your cert flight!
     
  6. Jun 12, 2019 #6

    mbeels

    mbeels

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    Yeah, check animal motor works, although I don't know if their offer is current, send them an email.
     
  7. Jun 12, 2019 #7

    crossfire

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    I really like the DMS line of motors. I put together my 1st AT reload in years a week ago. It was the J520 haz mat free motor.
     
    Last edited: Jun 12, 2019
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  8. Jun 12, 2019 #8

    Arsenal78

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    Do an Aerotech DMS motor like the H115 for your cert flights. CTI is having some issues as of current with catos in their motors, specifically the 38mm line. The only Aerotech I use is for 24/40, 29-40/120 hobby cases and DMS motors. Other than that, I go with Loki stuff. Easier to build than Aerotech, no hazmat from G-I impulse with the exception of two motors, you support a smaller fish, and you get more bang for your buck (more impulse per dollar spent) and no other company's I motor can match the I405 lol.
     
  9. Jun 16, 2019 #9

    grouch

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    The AT DMS line is pretty cool. I watched 45+ J425 Reds go off yesterday without a hitch. Needless to say I was impressed and will start to fly more of the throw aways.
     
  10. Jun 16, 2019 #10

    crossfire

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    That is very cool. Where was the launch held? Was it a special event?
     
  11. Jun 17, 2019 #11

    grouch

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    Yea it was the CANSAT competition sponsored by the US Naval Research Labs, NASA and a few others held at Tarleton State University. There was about 50 Extended LOC Minie Maggs stacked up like cordwood on hand to carry the student's CANSAT projects. I had no clue what I was getting into when I was heading down but there were teams from all over including Turkey, Korea and India. I am sure there were more but that's what I remember. I was seriously impressed and the kids were awesome to work with. Al and Karen Gloer, Tony ManixFan and his son and myself were all lucky enough to serve as pad monkeys for the launch.
     
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