Aerotech RMS 18mm D2.3T nozzle throat issues

I am using these for a project, and when dry-fitting everything prior to setup, I discovered that the nozzle throat is not large enough to let the pyrogen pass through.

Also, the heat shrink tubing is also too large to pass through, as I though loading the igniter first, then closing up the casing may work. No joy on this one.

I am using the mini igniters that come with the motors, and all the nozzles and igniters suffer this issue.

Any help or advice is appreciated.

Typically it is acceptable to assemble these motors with the igniter inserted during assembly of the motor. I know we (TriCities Rocketeers) allow this for certain motors where the throat is too small for on the pad insertion. Contact the club you plan on flying with for their procedures on this scenario.

^^^ That and in case of a misfire keep motor held fore end down when disassembling and inserting new igniter. A friend did not do that and melted his forward closure when it ignited.

rharshberger said:

Typically it is acceptable to assemble these motors with the igniter inserted during assembly of the motor. I know we (TriCities Rocketeers) allow this for certain motors where the throat is too small for on the pad insertion. Contact the club you plan on flying with for their procedures on this scenario.

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That was plan B. The heat shrink tube that is holding the wires together by the pyrogen is also too large for the throat. I could cut it off, but I am concerned about the pyrogen being stressed.

The heat shrink should pull/slide right off.

timbucktoo said:

The heat shrink should pull/slide right off.

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I will try again. It seemed pretty attached.

Thank you.

I love these 18mm D motors. The directions tell you how to get around the pyrogen being too large. They do not however address the heat shrink problem. What I do here is very carefully remove and discard it, sometimes I get lucky and it just slides down all the way off. When it doesn’t I very carefully cut a slit in it with a sharp blade.

solid_fuel said:

I love these 18mm D motors. The directions tell you how to get around the pyrogen being too large. They do not however address the heat shrink problem. What I do here is very carefully remove and discard it, sometimes I get lucky and it just slides down all the way off. When it doesn’t I very carefully cut a slit in it with a sharp blade.

Click to expand...

I saw that, but I ran into the heat shrink issue. I will try that when I get home and see how actually stuck the tubing is, and go from there.

be sure to get the heat shrink off, i have had one CATO on me due to it plugging the nozzle.