Stuck NPT fittings
Probably a noob question. I'm almost done building my first gun, but I'm having trouble with the threaded fittings. The male fitting is NPT Sch80 PVC, and the female fitting is NPT Sch40 PVC (this is for a combustion gun, I couldn't find the male fitting I needed in Sch40). Anyway, I can't get the male fitting to go in all the way. It gets tighter as it goes and gets stuck about 2/3rds of the way in. Both the male and female are supposed to be tapered threads according to McMaster (straight is NPS instead of NPT, right?). On Burnt Latke's site he recommeded filing down the little imperfections in the thread seams, but that doesn't seem to have helped. I also tried lubricating the threads with a little WD-40 but that didn't help either. Any suggestions?
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squeaks
- Specialist 3
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hahahahaha............sorry, had to laugh at this one.
NPT fittings are supposed to get tight until the point where you can't turn them anymore. This is so that a proper seal can be acquired. It's perfectly fine to have some of the threads not being used. Just remember to teflon the threads.
NPT fittings are supposed to get tight until the point where you can't turn them anymore. This is so that a proper seal can be acquired. It's perfectly fine to have some of the threads not being used. Just remember to teflon the threads.
"Nine out of ten Americans agree that out of ten Americans one will always disagree with the other nine."
-Collin Mockery
Who's Line is it Anyway
Borrow money from a pessimist, he won't expect it back.
-Collin Mockery
Who's Line is it Anyway
Borrow money from a pessimist, he won't expect it back.
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squeaks
- Specialist 3
- Posts: 326
- Joined: Sun Oct 01, 2006 5:45 pm
- Location: Enoch, UT(next to Cedar City)
I was taking it easy. That's why I was enjoying this moment for some comic releif. Yeah, I knew about just as much when I first started. Then I discovered the joy of the forum search key and spudwiki. Two lifesavers.
"Nine out of ten Americans agree that out of ten Americans one will always disagree with the other nine."
-Collin Mockery
Who's Line is it Anyway
Borrow money from a pessimist, he won't expect it back.
-Collin Mockery
Who's Line is it Anyway
Borrow money from a pessimist, he won't expect it back.
squeaks wrote:I was taking it easy. That's why I was enjoying this moment for some comic releif. Yeah, I knew about just as much when I first started. Then I discovered the joy of the forum search key and spudwiki. Two lifesavers.
No harm, no foul. But just for the record I did spend about an hour searching the forums, reading, and going through the Wiki, and didn't see anything mentioned about stuck threaded fittings.
Actually, all together I've probably spent three or four hours reading through the forums here, and I think I saw more posts about forum etiquette, grammar, and spelling than about spudguns...
Anyway, thanks for the sanity check, everybody.
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squeaks
- Specialist 3
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- Joined: Sun Oct 01, 2006 5:45 pm
- Location: Enoch, UT(next to Cedar City)
Yeah, we are a bit nutz here about grammar and whatnot. In fact, just by typing this message someone will proofread me and fix any and all spelling/grammar errors. That or they will make fun of me for whatever dumb reason I'm posting this message. That's half of the fun of the forum.
"Nine out of ten Americans agree that out of ten Americans one will always disagree with the other nine."
-Collin Mockery
Who's Line is it Anyway
Borrow money from a pessimist, he won't expect it back.
-Collin Mockery
Who's Line is it Anyway
Borrow money from a pessimist, he won't expect it back.
ugh. you spelled "nuts" wrong!!!
lol, jk
ya, when i first started i thought that you had to get them almost all the way in...but then i realised that that wast possible.lol.
lol, jk
ya, when i first started i thought that you had to get them almost all the way in...but then i realised that that wast possible.lol.
There are rules, and then there are hundred dollar bills.
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Pete Zaria
- Corporal 5
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- Joined: Fri Mar 31, 2006 6:04 pm
- Location: Near Seattle, WA
Snowjack,
Two strap wrenches (like these:
) work wonders on stuck threaded fittings.
I don't know if they'd shrink at all if you put them in the freezer to get them cold - it might help, and I don't think it could hurt them...
Peace,
Pete Zaria.
Two strap wrenches (like these:
) work wonders on stuck threaded fittings. I don't know if they'd shrink at all if you put them in the freezer to get them cold - it might help, and I don't think it could hurt them...
Peace,
Pete Zaria.
