Air System in the shop

[Shuswap Pat]

Just got the shop (almost) finished, and now need to run air lines. I was looking at the Rapid Air system as was wondering if anyone has installed one? It is limited to 1/2" Tubing ( about .400 id), but I think that will do for the major amount of stuff I need. Any large consumption needs, I can run a line right from the compressor (5HP - 60 gallon tank).

Patrick

[Wheels17]

A quick google on RapidAir 3/4in. MaxLine Master Kit, Model# M7500 shows a 3/4" kit being sold at Home Depot, Sears, Northern Tool, Eastwood, Rural King........

[krutch]

You'll have to deal with coil "set" that is tough to relax. And fittings which will leak due to their nature and the coil "set" of the 1/2" OD hose. It is quick to install. But the 3/4" system is a bit better. It will give more CFM delivery at the working end of the line than the rapid-airs smaller tubing. And the larger system has better fitting connectors.

[HSS]

I installed the 3/4" in my shop and the tight coils weren't a problem. If moisture isn't going to be a problem, then the tubing is great, otherwise you will need a good water separator. The end fittings, which are actually tees, have a drain petcock to blow out some of the water.

[Mike279]

I liked the fittings but the leaks drove me crazy. I put copper water pipe in place of the plastic lines. Very happy now. Mike

[Doozer]

I was thinking about doing my shop in PEX.
3/4 for the runs at the ceiling, and 1/2 for the pipes
coming down the wall. I would use the crimp rings
not the squeeze clamps.
Q? How UV stable is it? Will it explode without warning
like PVC? I am smarter than to use PVC (I am not a
cheap skate). I did my last shop in 1/2 galvanized
steel pipe. I took it all down when I moved and I
stll have the pipe and fittings (Ward USA).
I just used some PEX around the house for
moving some sinks, etc. and I think it would be
great for the shop air system. Any thoughts?

--Doozer

[boslab]

Id run a 3" or even bigger ring around the ceiling and drop downs to air points with drains, acts like a second receiver or accumulator, handy.
Mark

[Bruce Griffing]

I used PEX in my shop attic with copper drops down the inside surface of the wall. Easy to do and hard to damage the copper in the shop. Works well.

[sawlog]

I did the same thing. Has a lot of PEX laying around and run a line around the shop to move a hose reel outsided for tire inflation and such.. Then I have a fitting for my blow gun.. Granted I have a small shop and a small air compressor but i keep 120psi on my lines all the time. It has been 8 months now and I have not had any problems

[Rosco-P]

I used PEX in my shop attic with copper drops down the inside surface of the wall. Easy to do and hard to damage the copper in the shop. Works well.

The makers of PEX explicitly state that it's not for compressed air lines. If it's working for you be happy. If it fails at least the damage, if any will be confined to an occupied space.

My distribution lines are 1" black pipe. If copper was cheaper, I would have used L weight.

[JoeBean]

Yes, PEX degrades when exposed to UV. Most manufacturers explicitly warn about keeping it out of UV before installation. Also, all the PEX for water that I've seen is rated at 200PSI max, BUT that's at something like 20 or 23C (~70F). As temperature increases max PSI quickly decreases. So if you're going to use PEX, you probably should:
a) Keep it concealed from UV
b) Use a whip hose or copper for the first 10' or 20' (depending on compressor size/cycling time) or so from the compressor as temp is higher the closer to the compressor you are
c) Regulate the pressure down to 120PSI or max near the compressor.

I'd have no concerns using PEX like Bruce does in a sheltered area, but not having seen PEX explode I'd be very cautious about having it anywhere where I could be hit with shrapnel.

Iron is pretty cheap, and even Copper isn't too expensive. And if you plan your piping layout properly you can save a lot of pipe.

[Frank Ford]

It seems I'm always moving tools and rearranging my small shop, so whatever wiring and plumbing I do needs to be changeable.

For the last dozen years or so, my shop has been "plumbed" with regular rubber air hose with nary a leak or problem. I don't use LOTS of air but it's important to me - my compressor is a Quincy 60 gal. 5 HP vertical unit.

I can replumb the entire place in an afternoon, or cut and paste any changes or new lines I want it a matter of a few minutes because it's all just plain rubber hose with worm clamps and "T" fittings:

[krutch]

I installed the 3/4" in my shop and the tight coils weren't a problem. If moisture isn't going to be a problem, then the tubing is great, otherwise you will need a good water separator. The end fittings, which are actually tees, have a drain petcock to blow out some of the water.

I have both the 3/4" and the 1/2". It is the 1/2" that has "coil" issues. The 3/4" has a metal core that helps when straightening or bending it. The 1/2" has quick connect fittings and between the coil and fittings can be a bitch to end leaks.
From my experience the 3/4 is the better system. More expensive maybe but worth costs. My air impact driver likes it better than the smaller line. Blast cabinet works better also.

[JoeBean]

It seems I'm always moving tools and rearranging my small shop, so whatever wiring and plumbing I do needs to be changeable.

For the last dozen years or so, my shop has been "plumbed" with regular rubber air hose with nary a leak or problem. I don't use LOTS of air but it's important to me - my compressor is a Quincy 60 gal. 5 HP vertical unit.

I can replumb the entire place in an afternoon, or cut and paste any changes or new lines I want it a matter of a few minutes because it's all just plain rubber hose with worm clamps and "T" fittings:

Neat idea. What diameter hose are you using? How long are the runs? And do you use/have any problems with higher CFM tools, like spray guns, blast cabinets, or oscillating sanders?

[alsinaj]

I've been using the same system as Frank Ford for 10 years. I have a "T" near my compressor with a quick connect for a 1/2" ID rubber hose when I need to run something that takes a lot of air, like a pressure blaster. But the shop distribution system is just 3/8" ID rubber hose, with Ts and hose clamps. The only problem I have had is when I bought some 3/8" hose that turned out to be closer to 7/16". That caused leaks at the fittings. Other than that, no problems. It's cheap, easy to install/modify, and it works fine. My compressor is a Kellog 321TV with an old-fashioned cast-iron 1.5 HP motor. Both are over 60 years old; both have been rebuilt once; both are and going strong.