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)
 
https://www.lokiresearch.com/secure/storeDetail.asp?id=52120032164096
A couple issues come to mind. It's possible the bulk head was not tapped properly, after the anodizing process the threads could have something stuck in there.

A 3/8" - 16 tap or thread chaser can be used to clean the threads up.

~John

Edit: tap size, thank you for reading.
 
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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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