This H219T-14A has a thrust ring.
https://www.apogeerockets.com/Rocke...or-H219T-14A?zenid=dsl8jemi1uai8rfb54pl911ap1
However some motors SU do not have one currently. Like this I140W.
https://www.apogeerockets.com/Rocke...ingle_Use/Aerotech_38mm_Motor_I140W-14A_HP_SU
Hey do have a thrust ring built into them. I got my L2 earlier this year using a DMS motor.
I had something similar... I think? I just used painters tape to tape over the nozzle. Didn’t totally seal it, but never had an issue. 2/2 while just taping to the end of the rocket wherever it would stick.Yes. I've flown the 29mm DMS motors. These come with caps to the nozzle extension (the part that protrudes from the aft end of the casing). Packed with the 38mm DMS motors there is a red cap for the ejection charge. but nothing for the nozzle.
The instructions for the 38mm DMS motor are the same as those for the 29mm motor -- and show a cap over a protruding nozzle
https://www.aerotech-rocketry.com/uploads/76b1c22b-afa5-4281-895f-fd7507a06752_29-54mm DMS Instructions 12-29-15 Small.pdf
View attachment 361556
The instructions give advice on what to do if there is no cap supplied, but are a silent on what to do if the motor doesn't have an "extension".
Here is what I am dealing with.
View attachment 361557
So advice or guidance on how to tape in the igniter would be appreciated.
I had something similar... I think? I just used painters tape to tape over the nozzle. Didn’t totally seal it, but never had an issue. 2/2 while just taping to the end of the rocket wherever it would stick.
I kinked the motor starter around a bolt on bottom of a 1010 rail after making sure the pyrogen was at top of top fuel grain for the 38mm dms. And the bolt kept the motor starter from falling out while rocket was vertical.
Tape it, anywhere, even if you wrap it along side of air frame. Not meant to seal seal nozzle, just need to hold igniter in place.
Here is one that I taped to rail:
For all types of motors I just wrap the leads of the igniter a few times around the standoff of the launch rail. For large diameter long motors taping the igniter to a small dowel allows them to be placed in the proper location in the motor.
Where does the dowel go?
Okay, my turn for a daffy question: I just opened the J270 so I could get a mass and COM for the rocket with the motor loaded
The instructions that came with the motor show the igniter held in place with a red plastic cap fitted over a protruding nozzle, but nozzle on the 38mm DMS motors is inside the thrust ring, and there is no cap included with the motor. What am I missing? What is the preferred method for holding the igniter in place?
How about a foam ear plug in the nozzle? The ones that roll real thin and then slowly swell back up.
Plugging a nozzle can cause a CATO from overpressure. If you haven’t personally tried this tactic with your own rocket and a DMS I would not be recommending it. In your idea it should combust. If it doesn’t ot oh. You know that Murphy guy likes to wreck stuff. Try tape or a external kink to standoff bolt to hold the igniter to somewhere on the launch rail it’s proven. Maybe I worry about introducing a problem. The other methods are flight proven. Not trying to be mean. Knife a slot into it my opinion if anybody wants to try earplug. But hey maybe I over worry.
Igniter gets taped to 1/8” dowel & gets shoved up to top grain but this is normally used on 75mm motors & larger.
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