loki 75mm bulkhead threads

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HVArcas

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For one longstanding project my plan has been to rretain a 75mm loki motor to a mid-body avbay and recovery system using the threads on the forward closure.

Today I went to thread it to some rod, and damn, it only goes in like 3-5 turns. I tried a cesaroni for sanity, and it went deep enough no one would worry about it. Other sanity check, I probed the threaded hole with a much smaller rod and could tell it went much, much deeper than the threads seem to allow (roughly the same as how far the ceso actually threaded)

So do the threads go all the way down? Does mine need a scrubbing or have some other physical problem? Or does the design only allow for what i have seen?

(oh btw I have a second bulkhead and it seems to be the same)
 

GalantVR41062

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Steve Shannon

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Perhaps it was tapped with a tapered tap rather than a plug tap. I would see it a tapered tap screws in further. If not, then it’s something else,but if a tapered tap goes in then I would use a plug tap to clean it out and then a bottoming tap.

 

heada

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Just pulled mine out of my range box. By hand, it was 8 1/2 to 9 complete turns from bottomed out to fully released. About 3/4in depth. The smoke recess has a very small vent hole that meets up to the tapped hole.
 
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