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The world of pipe fittings

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Re: The world of pipe fittings

#131

Post by scotty79 »

Kaibeezy wrote: post #40

All this plumbing talk got me remembering the time I redid a bunch of the copper in a fixer-upper. Reading up on solder joints, I got into the underlying metallurgy, and discovered solder isn’t “glue”. You have to abrade it to remove the oxide, quickly cover the raw copper with flux, and then let the boiling flux draw the molten solder into the joint. It doesn’t take much, and you end up with a metal-metal-metal bond…

I'm really not confident about copper pipes. Metals in solder are very different electrochemically than copper. There might be other electrically connected metals in the installation. There might be some impurities grains in the copper.

I've seen videos of copper pipes developing pinhole leak from corrision.

I always used aluPEX for doing the piping.

Re: The world of pipe fittings

#132

Post by beerandt »

VLM wrote: post #89
toss1 wrote: post #10

Earlier quoted context omitted.

Can confirm - also started using PEX recently, and it is fantastic - wouldn't go back for anything! Straightforward, solid, more resistant to freezing (tho I still drain/blow out the outside lines in winter). I've even had zero problems with the PEX-copper fittings; I generally just attach straight onto a cut pipe rather than an NPT fitting, so that may account for my different experience. I've run a few new lines in…

There are two problems with PEX in the shop, one real one joke. The joke one is PVC + UV = shrapnel, and frankly given enough time and vibration PVC doesn't need UV to shatter, so old timers hearing you're using plastic in the shop will freak out. (edited for those who don't get the joke: Pex will definitely split or crack under UV but AFAIK never shatters, so using PVC is a major OSHA violation but using unprotected…

Locally, we also have problems with rodents chewing threw unprotected pex. Probably because we rarely freeze, and unprotected really means completely unprotected.

Re: The world of pipe fittings

#133

Post by scotty79 »

toss1 wrote: post #113
VLM wrote: post #89

Earlier quoted context omitted.

There are two problems with PEX in the shop, one real one joke. The joke one is PVC + UV = shrapnel, and frankly given enough time and vibration PVC doesn't need UV to shatter, so old timers hearing you're using plastic in the shop will freak out. (edited for those who don't get the joke: Pex will definitely split or crack under UV but AFAIK never shatters, so using PVC is a major OSHA violation but using unprotected…

Thank you!! Very helpful tips, I appreciate it

There is a pex variant which consists of aluminium pipe with plastic layers on the inside and outside. This should combat low melting point of the plastic

Re: The world of pipe fittings

#134

Post by jcims »

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.

That’s beyond ’uncommon’, you should get a trophy.

Re: The world of pipe fittings

#135

Post by hilbert42 »

mindslight wrote: post #94
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.

That's only the way of the middle-aged. If you do it with just PTFE tape you'll be fine, but if you do it with all similar sundries, then you'll be oversaturated and once again won't be able to find anything without pawing through piles.

Right, see my reply to jcims but that's not all of matter. One could suppose I'm going senile and perhaps that's true but the fact is that I've been losing stuff like this since before I was a teenager.

I've figured out the problem: my mind is thinking about all sorts of seemingly important stuff all the time but which in fact is mostly garbage, so my subconscious mind handles what my conscious mind consideres as procedural or unimportant. As my conscious and subconscious minds aren't on speaking terms sufficient for my liking I often end up with the problem of lost stuff.

If I consciously tell myself where I've put something then I very rarely forget where it is. The trouble is I don't remind myself to make note often enough.

Re: The world of pipe fittings

#136

Post by hilbert42 »

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.

One has to ask 'finished it doing what'.

Re: The world of pipe fittings

#137

Post by msrenee »

jasonwatkinspdx wrote: post #17
thedanbob wrote: post #6

I had a major plumbing problem some time ago (leak in the house’s main line) and paid a plumber way too much to dig a hole and fix it. I of course wasn’t about to pay him to fill the hole back up, and while it was open I took a good look. That’s when I discovered PEX. PEX is wonderful: easy to work with, inexpensive, simple to fix if you screw something up. I wish all plumbing was PEX. I briefly installed an NPT flow…

Came here to also plug PEX. A friend used it for his remodel, did most of the work himself, and set everything up so all the lines come down to a sort of "switchboard" panel in his basement, so that as he did more remodeling work in the future he could disconnect individual loops trivially. It just makes so much sense and is so easy vs copper pipe. Amusingly he told me one of the plumbers he did get a bid from said s…

It breaks down pretty quickly when exposed to light, chlorine, and excessive heat. It's also very easy to damage. A kid being an idiot or rats and mice gnawing on everything like they do and you've got a heck of a leak that hopefully is caught quickly.

Seems like there's lots of situations where it's a good choice and lots of situations where it's not.

Re: The world of pipe fittings

#138

Post by mgarfias »

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…

A small quibble: the tape don’t seal. It’s a lubricant for the threads wedging together to seal.

For a REALLY good primer on the subject, read Carrol Smith’s _Nuts, Bolts, Fasteners and Plumbing Handbook_ (aka Screw to Win).

Re: The world of pipe fittings

#139

Post by kevin_thibedeau »

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?

When you open up the joint, bits are left behind in the female half. Then they get pushed in when it's resealed.

Re: The world of pipe fittings

#140

Post by kevin_thibedeau »

Severian wrote: post #90
throwawayacc4 wrote: post #82

This article sucks. Lots of bad info from an inexperienced plumber. How the US military, nuclear power plants, and plumbers worth their weight in salt do fittings: 3-4 times around the (male) fitting with PTFE tape, then a light amount of pipe dope on top of the PTFE tape. Also, DO NOT buy the cheap PTFE tape as suggest. Buy the milspec tape. Your big box store will have both and you'll know where that money (a coupl…

Milspec, lol. Doesn't that normally equal as cheap as they can get away with? There is a high-density thread sealing PTFE tape that works a bit better than the el' cheapo generic white stuff (although it's usually white too). Anything marked as such should be sufficient unless you are working on an oil rig or nuclear reactor. EDIT: Unless the package has MIL-T-27730 on the tape, labeling it milspec has no meaning.

> Milspec, lol. Doesn't that normally equal as cheap as they can get away with?

It means a product meets stringent requirements that can't be cheated on.

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