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The world of pipe fittings

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Re: The world of pipe fittings

#221

Post by bombela »

hilbert42 wrote: post #213
semireg wrote: post #196

Earlier quoted context omitted.

I just bought 24x 6” stainless steel rulers because every time I’d reach for one it’d be across the room at a different desk. Now I can capture a dozen at a time in their remote location for rehoming. Problem solved. Also on my list of buy too many so I’m never left without: sharpies, microfiber cloths, jumper cables, rice (carbs), frozen sliced sourdough (fancy carbs), pocketable protein/energy bars.

I know, 12" rules are bad enough at disappearing but 6" ones seem as fleeting and ephemeral as the wind. At least it's nice that one can now purchase them in packs of a dozen or so.

I am glad to be using metric. 150mm and 30cm rulers don't seems to run as fast as theirs us customary unit counterparts ;)

Re: The world of pipe fittings

#222

Post by lazide »

culopatin wrote: post #112
VLM wrote: post #86

Earlier quoted context omitted.

Tape causes massive contamination problems with fuel and hydraulic systems. Its not that the Teflon reacts with hyd oil, its that the inevitably little tiny bits of stuff physically jam/ruin seals and clog nozzles.

But only if you put the tape over the edge. I usually leave the first 2 threads uncovered, why would it fall into the stream if you don’t cover the tip of the thread with it?

The tip of the thread in NPT is the one that needs the lubrication the most, hah.

Pipe Dope causes similar issues though.

Re: The world of pipe fittings

#224

Post by lazide »

XorNot wrote: post #198
jakewins wrote: post #182

Earlier quoted context omitted.

Do you have a reference for this? Everything I've read is the purpose of the tape is to reduce friction (hence PTFE), not to actually seal. In other words, the seal comes from the fittings connecting tightly, made possible by 2-3 wraps of PTFE low friction tape.

PTFE tape is meant to block the helical path around the screw threads for leaks to propagate. For parallel threads it's absolutely vital. Taper threads are designed to crush together to achieve something similar, but for what's available at the hardware store I've always had problems.

That is a common falsehood.

Parallel threads need an alternative sealing method, or they’ll leak. If low pressure, dope or tape might be enough, but it’s using the fitting wrong.

Usually there is a flare, mating surface, or o-ring type setup that should be used instead. Examples would be welding tank connections, or scuba tanks that are at thousands of PSI.

For NPT, if the fitting is properly tightened, the fitting deforms and the threads mash together. They won’t leak even at hundred of PSI.

Re: The world of pipe fittings

#225

Post by fijiaarone »

sokoloff wrote: post #99
jcims wrote: post #78

Earlier quoted context omitted.

>Of course—not being plumber—it often happens that when I urgently need PTFE tape I cannot find it Ahh, young padawan, the way of the elder is to buy a roll every time you have a project to do until you have achieved saturation...where there is a lightly used roll of teflon tape in every drawer and on every surface of your workshop and garage.

I unlocked an uncommon DIY achievement last month: I finished an entire 119 foot roll of PTFE tape.

All I have is Teflon tape, but I’ve never finished a roll. I think they sell them in only 3 feet sections now, but still the same spool size.

Re: The world of pipe fittings

#226

Post by Sophistifunk »

hilbert42 wrote: post #63
SaintGhurka wrote: post #45

Earlier quoted context omitted.

"combination of Hessian/burlap jute-type rope (of which there is always some lying around in my workshop) and linseed oil based paint." Could you explain that? How do you seal pipe fittings with rope? Edit: found an explanation. TIL that you can use the fibers just like tape and wrap the threads.

Perhaps if I'd used the proper name what I said may have been clearer. The correct name is hemp rope or plumber's rope but I don't often have that around (not being a plumber) so I use the next best thing available Hessian fabric or its rope equivalent). Here are some photos: https://www.bunnings.com.au/enduraseal-1m-plumbers-hemp_p012... https://waropes.com.au/twines/plumbers-hemp/ You wrap the hemp fibers around th…

That seems hella useful, I'm going to grab some next time I'm down picking up a snag sanga.

Re: The world of pipe fittings

#227

Post by bdowling »

jkqwzsoo wrote: post #9

In case anyone from the US reads this, BSPP and BSPT fittings are rare and incredibly frustrating here, as our NPT (National Pipe Taper) threads are different and the selection of BSP(P/T) fittings is extremely poor in comparison. Also, I work with NPT fittings quite a lot: > For what it’s worth, I tightly wrap the tape 10 times round the male thread and get an enraged mountain gorilla to tighten it up. This is a WTF…

> This is a WTF NO!!!

I’m pretty sure the author was exaggerating, because no sane person would use an enraged gorilla to tighten fittings. Gorillas are simply far too dangerous to be trusted with important plumbing work.

Re: The world of pipe fittings

#228

Post by TheJoeMan »

jkqwzsoo wrote: post #9

In case anyone from the US reads this, BSPP and BSPT fittings are rare and incredibly frustrating here, as our NPT (National Pipe Taper) threads are different and the selection of BSP(P/T) fittings is extremely poor in comparison. Also, I work with NPT fittings quite a lot: > For what it’s worth, I tightly wrap the tape 10 times round the male thread and get an enraged mountain gorilla to tighten it up. This is a WTF…

> when someone inexperienced first learns what pipe tape is, they try to apply it to everything

I just removed some from a medical oxygen DISS fitting, which is a conical seat on the inside meaning the threads do 0 sealing duh-oh.

Re: The world of pipe fittings

#229

Post by klyrs »

bdowling wrote: post #227
jkqwzsoo wrote: post #9

In case anyone from the US reads this, BSPP and BSPT fittings are rare and incredibly frustrating here, as our NPT (National Pipe Taper) threads are different and the selection of BSP(P/T) fittings is extremely poor in comparison. Also, I work with NPT fittings quite a lot: > For what it’s worth, I tightly wrap the tape 10 times round the male thread and get an enraged mountain gorilla to tighten it up. This is a WTF…

> This is a WTF NO!!! I’m pretty sure the author was exaggerating, because no sane person would use an enraged gorilla to tighten fittings. Gorillas are simply far too dangerous to be trusted with important plumbing work.

If you think plumbers are expensive, you've never tried to hire a gorilla for an hour.

Re: The world of pipe fittings

#230

Post by thedanbob »

schemescape wrote: post #22
bilsbie wrote: post #20

Earlier quoted context omitted.

What’s the one that leaks and you’re supposed to replace?

Probably polybutylene: https://en.m.wikipedia.org/wiki/Polybutylene

That’s the one my house was plumbed with. I’ve already had to patch two random leaks. I don’t yet have the motivation to fix the whole house so I just keep PEX tools and parts handy in case it fails somewhere else.
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