Kosdon motor question

Discussion in 'Propulsion' started by Mike Nixon, Jan 12, 2019.

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  1. Jan 12, 2019 #1

    Mike Nixon

    Mike Nixon

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    I've been out of the hobby for a while and have an old Kosdon case. It's a 54mm 2550 motor case from the 90's. What do I need in order to use CTI reloads in it?
     
  2. Jan 12, 2019 #2

    Eric

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    I don't think there is any cross compatibility in the 54mm size.
     
  3. Jan 12, 2019 #3

    dhbarr

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    AFAIK none of the 54's are cross-compatible, only 75's?
     
  4. Jan 12, 2019 #4

    Dave A

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    If you are ONLY using the 54/2550 AMW compatible loads made by CTI you will need: an AMW/CTI nozzle carrier, nozzle washer, 2 snap rings and Kosdon/AMW fwd closure. It comes assembled with it's own disposable nozzle.

    CTI Pro54 loads will NOT work in a 54mm snap ring case.

    If you find any of the AMW or Kosdon compatible loads by Aerotech , then you will use all the usual snap ring hdw and nozzle to fly those.

    Loki reloads will work in your case provided the fwd closure is the correct length.
     
  5. Jan 12, 2019 #5

    Mike Nixon

    Mike Nixon

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    Thanks for the help guys!
     
  6. Jan 12, 2019 #6

    Loki Research

    Loki Research

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    Since it was brought up, I'd like to elaborate/clarify this for Mike.
    To fly the majority of Loki Research 54/2800 reloads in the AMW 54/2550 case, all the other components except for the snap rings need to be Loki Research brand. The Standard Forward Bulkhead, #42 nozzle and Nozzle Washer found on this page here. The 2 standard snap rings can be of any brand for that size case.

    To fly the L-1040 Loki Red (largest reload currently available for this size case) you only need a Loki "Extended" Forward Bulkhead, 2-turn internal retaining ring, and a custom ground retaining ring. They can be found on the same page as the other 54mm parts. I just cast more of these loads this week too.
    The Loki 54/2800 and AMW 54/2550 cases are the same thing, just different nomenclature. Same goes for the 54/1200 vs 1050 and 54/2000 vs 1750.
     
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  7. Jan 12, 2019 #7

    jimzcatz

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    As Dave mentioned there are loads for that case, but were recently discontinued. Both Aerotech (KBA line) and CTI (AMW/PROX line).
     
  8. Jan 12, 2019 #8

    Dave A

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    I have flown Loki, AMW and KBA loads using a mix of nozzles(if the right size for the load) and other fwd closures.
    UNDERSTAND: I should have mentioned that mixing parts now makes it a research motor. I have methods of doing this with my own way of doing a different tracking smoke, fwd, etc. It depends on what fwds I have and which style is the reload.
    If you do not feel comfortable or understand what this can do, DON"T DO IT!.
    I STILL have AMW loads Paul made and KBA from when Frank was alive. I prefer the Loki loads and fwd, they have lots of kick in my book and are engineered very well.
     
  9. Jan 13, 2019 at 2:34 AM #9

    Loki Research

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    What Dave was talking about may or may not make it a certified motor. It depends on the parts you use.
    The combination I mentioned above does constitute a certified motor. Basically if you take all the parts from the hardware of a Loki Research 54/1200, 54/2000, 54/2800, 76/3600, 76/6000 or a 76/8000 and you swap out the Loki motor case only for a Kosdon, AMW or Gorilla motor case, you still have a certified motor.

    The only specific detail I would mention is that if you are using a Gorilla 54/2550 case, you should use a 2nd nozzle washer as a spacer at the head end of the motor. There is 0.100" more room between the snap rings on the Gorilla 54/2550 case than there is on all the other brands in that size.
    If a Gorilla 54/2550 case it is used with the Loki L-1040LR, replace "should use" with "ABSOLUTELY MUST USE". It will probably fail with a forward end burn through if you do not. Actually you'd need to contact me for a special nozzle washer since the standard washers won't fit over the larger diameter Extended Forward Bulkhead.

    If you want to use some other combination of parts for any size motor, Dave is the main go to guy. That's one great thing about snap ring motors for experimental use, there are an endless combinations that can work together and Dave has tried many of them.
     
  10. Jan 13, 2019 at 9:36 PM #10

    Dave A

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    Scott,
    Thank you for the kind words. I have been fortunate to load most any snap-ring reload in most any case. I have Loki, AMW, Kosdon and EX cases in 54mm & 75mm. I also have Loki, AMW and Kosdon FWDs and nozzles.
    Sometimes spacing is an issue and I always fill in with nozzle washers. Again with careful thought and assembly, I've not had any failure or scorching. Older AMM and Kosdon reloads come with paper phenolic liners for which I am not a fan. I have had burn-throughs, sometimes nearly the length of the liner, no scorching yet. Glad I coat the outside of the entire liner well with grease.
     
    Last edited: Jan 14, 2019 at 9:34 PM
  11. Jan 13, 2019 at 11:32 PM #11

    Mike Nixon

    Mike Nixon

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    I appreciate everyones input!
     

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