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Bruce

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We're having difficulty with ignition of a D13W in an 18/20 case. We got the first one to light on the 2nd try. But the second one has gone thru 2 ignitors and still hasn't lit. Figured we must be doing something wrong.

We have triple checked and the ignitor is in the slot and is pushed ALL the way up to the top. The ignitor wire was secured with masking tape to keep it from moving down. Each time the ignitor and it's pyrogen burn without igniting the propellant.

I realize that this motor has a small nozzle throat diameter requiring the ignitor to be small with a limited amount of pyrogen. But we've had 100% ignition reliability on a dozen firings of our 24mm E6-RCT reload which has an even smaller nozzle.

Any suggestions or advice?
 

AeroTech

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We're having difficulty with ignition of a D13W in an 18/20 case. We got the first one to light on the 2nd try. But the second one has gone thru 2 ignitors and still hasn't lit. Figured we must be doing something wrong.

We have triple checked and the ignitor is in the slot and is pushed ALL the way up to the top. The ignitor wire was secured with masking tape to keep it from moving down. Each time the ignitor and it's pyrogen burn without igniting the propellant.

I realize that this motor has a small nozzle throat diameter requiring the ignitor to be small with a limited amount of pyrogen. But we've had 100% ignition reliability on a dozen firings of our 24mm E6-RCT reload which has an even smaller nozzle.

Any suggestions or advice?
Try roughing up the slot in the grain with a knife or fingernail file.
 

ghuber

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I'm not sure if this is the right thread to ask this on, but does anyone have experience with the M1340 and whether one can bond a hardpoint for recovery hardware into the forward bulkhead? (where a charge well would normally be located).

This thread has a great photo, as do the instructions, and it sure looks like a solid attachment point, but I'm not sure.


Thank you -Greg
 

tfish

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I'm not sure if this is the right thread to ask this on, but does anyone have experience with the M1340 and whether one can bond a hardpoint for recovery hardware into the forward bulkhead? (where a charge well would normally be located).

This thread has a great photo, as do the instructions, and it sure looks like a solid attachment point, but I'm not sure.


Thank you -Greg
The M1340 DMS motor comes with an aluminum Forward Closure that has a 3/8-16 threads built into it..

Tony
 

ghuber

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Mea culpa, I realize I mixed up the M1340 DMS (98mm) and the M1350 DMS (75mm). Is the M1350 the same in terms of having the threaded aluminum forward closure? Also, does anyone have experience using it for mounting recovery hardware? Thanks again.
 

AeroTech

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Mea culpa, I realize I mixed up the M1340 DMS (98mm) and the M1350 DMS (75mm). Is the M1350 the same in terms of having the threaded aluminum forward closure? Also, does anyone have experience using it for mounting recovery hardware? Thanks again.
Yes.
 

AeroTech

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Join us at NSL 2021 in Alamosa, CO over Memorial Day weekend, the first big NAR launch event in over a year! We'll be demo flying some cool and exciting new stuff!!
2021 NSL Ad (1) copy.jpg
 

tfish

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Mea culpa, I realize I mixed up the M1340 DMS (98mm) and the M1350 DMS (75mm). Is the M1350 the same in terms of having the threaded aluminum forward closure? Also, does anyone have experience using it for mounting recovery hardware? Thanks again.
Using the threads on an aluminum Forward Closure is the strongest anchor point on our rockets. You still need to take some precautionary steps...

1. Retain the motor to keep if from falling out. Aft motor retainer or other retention or held in via those same threads to an internal bulkhead.
2. You also need to keep your attachment point Forged or welded eye bolt or eye nut..from unscrewing itself. Yes it CAN and DOES unscrew it self. Jam nuts or other restraining methods work.

20210421_083902.jpg


Tony
 
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