QC air fittings - leaking

[LCHIEN]

Is it common for QC air fittings to leak a small amount of air - audibly?
I have a mix of HF and Husky and C-H brass fittings, the HF of course were really inexpensive. Not sure i can tell them apart anymore. But the fitting between the QC on the end of the hose and the stud on the tool frequently leak audibly, i can stop the leak by rotating the fitting and or applying some sideways force on it.

Is this common for HF fittings or all fittings whether from HF or Husky or CH? Are the tolerances sloppy or is it a design issue.

Trying to figure out where i should start...

[Uncle Cracker]

I know most of mine do to some degree, even right out of the package. I think there are tolerance issues and differences between makers that make this a tough fix, unless you are willing to re-do all your fittings at one time to a single manufacturer, single lot.

[cabinetman]

I know most of mine do to some degree, even right out of the package. I think there are tolerance issues and differences between makers that make this a tough fix, unless you are willing to re-do all your fittings at one time to a single manufacturer, single lot.

I don't know if that's the absolute answer, but I usually do get them in bulk. I usually by 'Milton' and use them every day. If there's leakage, I check which fitting is the culprit (which ain't easy), and just pitch it. If you have a small tank, it can be kickin' on more than it needs to.
.

[dbhost]

I've got 3 of the QC sets from HF, and a fist full of old Milton fittings. I had to chuck one of my HF QC fittings as it leaked like a sieve... Everything else is tight. Mind you I had to do the same with my old Milton stuff until I got fittings that all, well... fit.

No matter the MFG, it seems that QC fittings are pretty hit or miss in fit and finish. The HF ones seem no worse than the name brand ones. But they are certainly no better either...

[thrytis]

I've noticed some differences in the innards of the female QC fittings. I've had problems with some from HF and Lowes leaking audibility, all of which you can see the exposed ball bearings inside that hold the fittings together. I found a different type (at Lowes) that has a rubber ring over the ball bearings to seal the connection. I think these were around $5 each, so a bit more expensive than the HF or cheap ones at Lowes, but i haven't noticed them leaking.

[tjr]

Have had pretty good luck with HF fittings, both the brass ones sold in sets and the steel ones included with some tools. The only thing I don't like is the the need to retract the ring on the female coupler while pushing in the male end, rather than just pushing in to connect.

Perhaps a bad question, but here goes: Are you using a mix of automotive and industrial fittings? If they'd hook together at all, they'd probably leak.

Also, based on past experience with water quick couplings, it appears that there's an o-ring way inside the female coupling - could it be that it's either gotten nicked or pushed out of its recess, maybe by a sharp male end?

[Charlie]

Deleted by me.

[LCHIEN]

Have had pretty good luck with HF fittings, both the brass ones sold in sets and the steel ones included with some tools. The only thing I don't like is the the need to retract the ring on the female coupler while pushing in the male end, rather than just pushing in to connect.

Perhaps a bad question, but here goes: Are you using a mix of automotive and industrial fittings? If they'd hook together at all, they'd probably leak.

Also, based on past experience with water quick couplings, it appears that there's an o-ring way inside the female coupling - could it be that it's either gotten nicked or pushed out of its recess, maybe by a sharp male end?

no they're all the same series (orange - the Automotive I think - )
I know better than that. I don't even think they mate (although I've seen universal ones that accept either (stud?).)

Buying them and useing them in sets is probably the answer...

buying them in matched pairs makes no sense, the usefulness in QC's is the ability to mix and match at will.

[sscherin]

About half the ones I get from HF leak to some degree or another..
The HF cast brass ones are the worst..

The ones I get from the pro tool store all hold great..
They look like they were machined.

I'll spend a extra buck to get a quality air fitting.

[Bill in Buena Park]

Loring,
I've had good luck with the HF air fittings, auto and industrial, and in the last 10 years I've only had 1 leak, but that was due to some strange oxidation on that fitting. The only HF QC couplings I've used were either auto or industrial only, not universal, and though they never leaked, I toss in favor of univeral QC couplings from Sears (the brass ones), which have worked great with both the auto and industrial from HF.

[dbhost]

I should mention, the HF fitting I had that was no good was the stud, and not the part with the coupler. You could actually see that it wasn't machined right. It was the brass set.

Not sure what the diff between automotive and industrial is. I just know the old Milton stuff I used when I was a mechanic, fits with no leaks whatsoever to my HF fittings I bought last month...

[LCHIEN]

...

Not sure what the diff between automotive and industrial is. ...

automotive and industrial are two different standards - they look very similar but they don't fit each other. mainly the grooves and rings are different on the male studs.

at the stores they usually code the automotive with orange tape or tags and the industrial with yellow so they don't get confused since they look so much alike. I think there's even a third standard coded with blue i forget the name.

I think Milton calls the automotive series the "M" series.

[BobSch]

I had a couple of HF sets that popped apart — usually when I was up a ladder or under something.

[Charlie]

Deleted by me.

[LCHIEN]

OK, the main problem was the end of my main hose leaking where I plugged the tools in. There's a small amount of play to misalign them, the leaks ocurred when the misalignment was maxed, if you held them so it was perfectly centered, it didn't leak but that's not a normal resting point.

So I did buy and check a new stud and female coupling from HD - a Husky part.
The hose female coupling was the culprit. When I put the new coupling in there was no leak with a couple of tools with studs I tried.

Well, the part I replaced was also a Husky - it was identical in nearly all respects including the stamping of the size and type on it. Well there was a couple of differences...
the opening on the bad one was .473" compared to .465" on the good one and the coupling had four balls (90 degrees separated) instead of three (120 degrees separated).
I looked and other couplings I have have three or four balls.

Anyway its the old Husky female QC coupling I had. Not the HF parts.