Compressed air fittings 101

[csi123]

I am new to air compressor and air tools in general, can anyone give me a crash course on how the fittings work?

Anyway I got a pancake air compressor with a hose that has 1/4 NPT quick connect fittings, and I have a tire inflation gun that comes with 1/4 NPT (the threaded non quick connect version), so how am I supposed to hook them up?

I went down to the store and they have 1/4 NPT coupler that will accept the male version on one side, and a quick connect on the other side. But there are like 5 or 6 different versions of them (M, P, V, H, A etc). The one on my compressor *looks* like the 'M' version.

So my questions:
- Is the 'M' version the most common/popular version?
- Should I use the coupler to attach the inflation gun to the hose that comes with the compressor? Or should I switch out the connector on the gun itself with a "quick connect" version? I tried to take the connector out and it seems to be screwed on pretty tight.
- Either way, when I put the coupler or new connector on, am I supposed to put some kind of *stuff* there, like tape, sealant, loctite, etc, so the gun wont fly off and kill someone?

 

[American Locomotive]

Can you post a picture of what fitting your tire inflation gun has? Is it a hose barb?

 

[seber]

Take your hose with you to the store and buy the mating QD male coupler for the gun. Put teflon tape on the threads before you screw it in. The couplings already have an o-ring to seal when you lock them together. The letter designations are actually one company's way of identifying the different types. There is actually an industry standard name for each one. The most common is "industrial interchange".

 

[sgs236]

This might help determine what type of coupler you have.

 

[theoldwizard1]

I have just stocked up on couplers and fitting from HF. The work fine for the average DIY and having a supply is very handy.

 

[Falcon67]

I have just stocked up on couplers and fitting from HF. The work fine for the average DIY and having a supply is very handy.

I tend to do the same at HD. Those also seem to work well and have decent life.

 

[GarageGuy89]

HF ones ****, HD/Lowes are a bit extra but dont leak and are worth it, we are talking pocket change.

If you buy a 'universal coupler' it accepts all/any male end so you don't have to worry about it ever again. There about $5 a piece, walmart is a good source for cheap brass ones. They have a red/blue/green stripe on them.

Use teflon tape on the threads helps with a seal. Again, buy from HD/Lowes, the HF teflon stuff is like 1/4 of the thickness and is ****. Again again, if you buy from HD they come with a pre-applied red sealant.

 

[Ole Slewfoot]

"automotive" fittings have a big end on the ****, "industrial" fittings have a big ring the tip protrudes out of. Pick one and roll with it. Universal females are available, and many are a little harder to operate. There are bigger sizes, but they won't appreciably help most common air tools.
I've got some old US made ones that are nicer, there is a difference, but it certainly isn't critical.

 

[Lelandwelds]

Milton makes great stuff for a good price. I couldn't begin to name where I bought all mine from. I make the purchase for some other item and add couplers because I will need them someday. If it won't seal, it gets trashed.

It is the female coupler body that leaks. If i had a source for the internal rubber seal, I would rebuild mine. It might be smarter to plan an intentional buy. Someday, I hope to switch everything to Milton V or Prevost.

 

[PhantomEB]

I switched out my various styles to all V style.

Now to cut up a 50’ hose into 2 20s and a 10.

 

[Elsinore13]

A Milton S715 coupler and some 727 and 728 fitting with teflon tape will have you set up to rock in most cases. Probably the most commonly used fittings around. Any Ace Hardware will have those.

 

[BDT/NWMN]

Yes the Milton M would be the most common... With the air equipment You mentioned, they will be more than adequate.

Put a 3 foot leader or whip hose on the inflation gun, with the coupler plug (S 728) on the other end. Put the female coupler (S 715) on the long hose that is attached to Your compressor.

By using the leader or whip hose as mentioned, You will not have to deal with that clunky coupler hanging onto Your inflation gun.

 

[d.mcfarland]

I upgraded to the high flow Milton's and am very happy. The female ends also accept the M style so you don't have to switch every last item if you don't want to.

 

[BDT/NWMN]

I upgraded to the high flow Milton's and am very happy. The female ends also accept the M style so you don't have to switch every last item if you don't want to.

I did the same upgrade on some of My medium sized air tools, such as 1/2" drive impact wrenches.. Altho the Milton V coupler willl fit either a style V or M plug, they require considerably more effort to connect than the Milton M coupler. I had planned on converting all My small and medium sized air equipment to the V, because they work great for improving the air flow in My favored 3/8" diameter air hoses.. Due to the added effort required to insert either plug into a type V coupler, I left the M couplers on some of the hoses, for use with the small stuff.

I have larger hoses and couplers for the 3/4" and 1" impacts and sand blasters.

I prefer to match air hoses and couplers to the work. I doubt the OP's pancake compressor and tire inflation gun would benefit from the use of a high flow type V coupler, so that is one application where I would stick with the Milton type M coupler.

 

[David0858]

I have just stocked up on couplers and fitting from HF. The work fine for the average DIY and having a supply is very handy.

Yep. I bought a bunch of HF connectors when I got my first compressor in March '01 and they're still going fine.

 

[PT Doc]

Start out right and go with Prevost safety couplers. Save your ear cause you know you will swap a tool under full hose pressure.

 

[On-Wheel]

Start out right and go with Prevost safety couplers. Save your ear cause you know you will swap a tool under full hose pressure.