Hardline air fittings

[TencenT]

Trying to follow some of the old information around hard line tubing just to try it out. The issue I'm running into is 1/8 npt doesn't seem to be 1/8 npt 😅. It seems the threads on ASAs and regulators are intended to be used with tapered fittings but the ones I'm finding online for the compression fittings seems to be straight thread so they don't fit. For example I have these and they start to thread and lock up almost instantly.

https://www.amazon.com/dp/B09FF4QS22

Am I just looking in the wrong place or missing something entirely here? Would love to get this working after realizing how easy it is to bend stainless tubing with bending tools.

[flyweightnate]

Cheap NPT fittings are often made wrong, as it's a tapered thread and therefore a little more complicated. Sometimes they'll even ship BSPP or BSPT and think you won't notice.

Try something with a DOT cert or from a reputable brand.

[TencenT]

You got a link to something? I have no idea what brands are reputable in the world of air fittings.

[Jsc5150]

Yeah this AI garbage is gonna replace me as a civil engineer but it can’t even output the same answer twice on the same page

[TencenT]

Heh.. yeah as a software dev I know the pain. It's not a replacement, it's a tool. Like any tool, used well it makes you faster. Attempting to replace actual engineering work with it will be a disaster

[fusion83]

Not the cheapest but whenever I use hardline on projects this is my go to combo

[DocsMachine]

It has to do with the fit. Not everyone follows the spec for the threads, especially, I've found, in paintball gear.

Because the threads are tapered, the 'fit" depends on how far you run the tap in. Run it in partway, and the fitting my get tight after only a thread or two. Run it in deeper, and some fittings may 'seat', but the fit to the actual threads is still pretty sloppy.

And they get away with it, knowing that you have to use teflon tape or pipe sealant anyway.

In that first Amazon link, those are knockoff Swagelok fittings- On one hand, the Swagelok stuff is very much industrial material, and the real stuff doesn't mess around with fit specs. That's the kind of thing you plumb reactor controls and million-gallon-a-day breweries with. On the other, that's clearly Chinese knock-off crap- they can't even spell "product" correctly- and who knows what they have for quality control.

It IS possible they also screwed up and did send you an NPS (National Pipe Straight) or BSP (British Standard Pipe) so it's worth checking.

Doc.

[TencenT]

The reg and asa are the inception ones so the threads are quite deep at least visually. I have no way to really validate them to the correct spec.

[TencenT]

So yor-lok is quality? This looks like what I need if so.

https://www.mcmaster.com/product/5182K807

[DocsMachine]

Yor-Lok, SwageLok, Parker A-Lok... Any of the name brands. And McMaster doesn't sell junk.

They're not as cheap as the Chinese knock-offs from Amazon, but speaking personally, I wouldn't use anything else.

Doc.

[screwloose45]

You can use regular paintball macroline fittings with 1/4 hard line.

[TencenT]

Makes sense, I'll give that a try. I guess the only difference that matters operationally is the PSI rating difference. I assume it's easy to cut the oring in them too.

[screwloose45]

Yeah can just use the macroline fitting orings. If you're using a pipe cutter you may have to sand down the flare it creates.

[TencenT]

This might be the way. The compression fittings come in tomorrow so I'll do a comparison on them. I will say the space between the reg and the ASA is tight on a karnivor so using the macroline fittings might be the most practical option for space.

[TencenT]

Tried it out with air fittings and thank you for that, now pretty obvious, tip. Works like a charm and makes disassembly far easier.