So I’m pressure testing my system with soapy water… I found two leaks, tried to tighten them more and it’s not doing anything. What do you guys typically do for this? Just take off the fitting, retape and try again? I saw some people heat the female threads or freeze the male threads or both, saw some thread “sealant” from HFS… just curious if anyone has a good way to get it sealed!
That’s what I do, I get the thick grey tape and do 4 wraps
Once taped, I try to do the full 2.5 turns after finger tight per recommendation for 1/4 npt and that usually seals things up.
It took me a bit to realize this personally, but tighter isn’t always better.
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What tape are you using? Taking it off and adding more tape is generally the way to go, but you’ve got to be careful with npt threads, I’ve definitely shredded a few going on and off. They stretch as you tighten it down.
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It says “venom tape” it’s white
I just looked it up, seems like good stuff. Add more I suppose
So you’re saying you take the fitting off, and just add more tape without removing the tape Thats already on?
I use the plain yellow gas tape and can get it you should be able to w the fancy stuff
I do like 2-3 wraps and wrap it opposite way your gonna turn the fitting
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Oh no, definitely need to clean all the old off then add more than before
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You should be wrapping the same direction you turn the threads, clockwise.
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really I was told different by a leader here hmm
I must have misunderstood them bc ur exactly right
If I’m wrong on that please get someone here to tell us why that would be the case. That’s gonna break my brain if that’s so. Lmfao 
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your right wrap it clockwise so it doesn’t unravel as u tighten
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Well thanks for the help fellas, gonna try again tomorrow!
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This is how I was taught. You want the tail end to face the opposite direction you rotate the fitting in so that it doesn’t bind up on itself
Fuel gas fittings are the opposite (left hand thread)
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Solong as your threading isn’t chewed, you’d be surprised how a little of the threading being damaged can cause minute leaks, even with liberal taping.
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If you plumb enough stainless, you should invest in a set of these for the common npt pitches:
Inspect your parts before threading them together, a good knick or burr on the crown of a pipe thread will often cause material to be scraped off and then gall up as the scraped material gets accumulated.
For the big bucks, by some go/no-go gauges.
Of course these are just tips, in this case I’d bet dollars to donuts you just need to retape and remake the connection. The turns past finger right is a good guideline but not worth all that much because there’s a large variation in how much you can get with finger right.
Generally, I wrap from the fat end, holding the part in my left hand and wrapping over and away from me to the narrow end of the thread, 2-3 wraps. Also, the only difference between the yellow and white tape (and all the other new variants) is the thickness of the tape. I only buy the cheap white stuff, it doesn’t make a damn but of difference
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Thanks guys! Just got done pressure testing everything and retaping a few fittings and got it all to be leak free (according to the soapy water method that is)
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Lots of good suggestions.
300 Series stainless on stainless galls badly, so you have to keep their surfaces away from one another. Otherwise you will put them together and they will still leak, but you can’t tighten them further, nor get them apart.
I stopped getting leaks, once I filled the threads even to their top with PTFE sealant, and then wrapped the threads with yellow PTFE tape.
It fills any gaps and keeps the surfaces from touching.
I also stopped designing NPT joints in favor of JIC. The expansion and contraction during low subzero extractions encourages leaks.
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