Graphite Nozzle Use

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Well-Known Member
Jul 3, 2014
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So I have various graphite nozzles, how fast can they be reused?

I know you need to clean off the slag and ensure the throat is clear, but does it need to sit and cool for a specified amount of time?

I have looked and could not find any reference to this anywhere. I messaged Scott at Loki, but also wanted to put this here so other people searching can find answers.
Thanks Tony, didn't know if it would be heat soaked and need some cooling period or not.

After cleaning out the throat and replacing the o-ring, you can use it again as quick as you can get a new motor assembled. Just don't burn yourself. Use leather gloves if it's still real hot when you remove it. The 38's cool down fairly fast in the shade.
Graphite actually gets stronger the hotter it gets, all the way to about 5,000F.

Scott Kormeier

Here is the response, Thanks Scott
Pretty much as fast as you can. Just clean out the nozzle throat. Entry / exit cones will burn up.

I think I flew the same case 3-4 times in one day with research motors when I first got into making them. By the time I recovered the rocket, the case was cool enough to touch. I took it apart and clean out the old liner. Cut a new liner, added more grains, replaced the O-rings and flew again. This was a Loki 38/480 case, nozzle, fwd closure - all reused.