My solution for airlines in my machine shop. Hard to track down a source for gasPex. Copper has gone way out of sight price-wise. Iron isn't cheap and besides having to deal with a bunch of possible leaks at the couplings and being a bear to route where I needed to route it, I settled on 3/4" 1 wire hydraulic hose. Compressed gas rated to 1,250 PSI and fairly tolerant to higher temps. Cost was $1.76 / foot delivered to my shop. JIC swivel ends were less than $5 each. From the air compressor, I needed to go up into the attic, under a floor in the loft, and then continue through another part of the attic to the point where I came through the ceiling tin and down to the first filter/regulator drop. I installed a tee where the hose came through the tin and branched off to the filter/regulator near the machine tools. I can't imagine that it would have been a pleasant job to fight it out with pipe couplings in the attic. Hose was nice. We ran a fish tape, taped the hyd. hose to it and pulled it to where it belonged. Here are some pics of the project:

 The compressor was set on top of the entryway hall to my computer office. This half of the shop is semi-heated and serves as a parking garage for our personal vehicles.

 A PVC 45° Street elbow served as a shield for the electrical service and air hose where they entered the attic. I added an auto-drain fitting to the compressor since I didn't want to climb up to the ledge and make a mess with draining the water. Purging every time the compressor cycles keeps water from building up and making a mess when it is manually drained. Notice the swivel JIC fittings where the hose hooks. Much nicer than fighting with pipe thread.

Air line is routed close to the ceiling to get to the drop near the lathe. The Tee is mounted where the first drop runs to the filter/regulator. The steel fitting serves as a protector from the sharp tin. Again, JIC swivels are oh, so much nicer than NPT threads, unions, pipe dope, etc.

Close up of one of the air outlets.

Buster, here's the kit I bought stuck to my Jet drill press. Cooler, mag base and filter was $300 some years back. I think they have gone up a bit since.

No, I didn't see a frost free nozzle at the time I bought the gun. The tubes do build up on the outside with white frost. Problems come from ice forming on the insides and plugging them. Take a short break, and they come unplugged and spit out a small ball of ice.

My Jet is the 5/8" chuck, 17" swing model. It is a decent drill press, but too much money for what you get IMHO. I've tested the chuck runout on the HF drillpress and it is better than the Jet and didn't cost nearly as much. If I had known then, what I know now, I'd have never bought a drill press for a primary drilling machine. Several things wrong with them for my purposes. First off, they turn way too fast for 3/8" and larger drill bits. I've remedied that problem by first building a chain driven jack-shaft and then later by fitting a 3-phase motor and VFD to reduce the speed to my preference. The next big problem with the drill presses is lack of spindle to column distance. A 17" swing drill press only had 8 1/2" of room from center of the drill to the column. For too many things, that isn't enough room.

Of course, being a farmer, there is nothing we like better than spending another guy's money. I'd advise doing what I should have done, and eventually ended up doing; buy a turret knee mill. Most of them have power downfeed on the spindle. The table can be moved in precise and measured increments on both the X & Y axes, so you can square your workpiece to it, and drill precisely spaced holes with no measuring, and accuracy within a thousandth of an inch or less. It isn't uncommon to see a mill with excess of 20" distance from spindle to column. My current machine has 26" so I can easily drill to the center of a 4 foot work piece. Most mills will have a slow speed in the neighborhood of 80 RPM. Much easier on things when you don't try to spin the big bits so fast.

EdB

I agree w/good idea on hyd hose for airlines. Thanks for pictures. I don't have way of making hoses @ home, but have always had local implement dealer make them for me where I need to make sharp bends in airlines, or something that's going to be moving a lot, like one of our auto-recoil air reels that also pivots. Making them at home has always been another mental project never done. Though, we do make our own 1/4, 3/8, & 1/2 air hose now w/slip-on fittings that never-ever give up.

But-anyway, what's wrong w/PEX for airline? I understand the pvc explosion thing, but I haven't been able to get any dangerous reactions from PEX.

Also-for extra air supply, I always recommend just procuring (buying?) an old 300-500-1000 gal LP tank & plumb it in to your system. The wall thickness on LP tanks is 20 times that of store-bought air tanks.

Ron, I expect PEX would be OK but the working pressure recommendations at higher temps concerned me a bit. In all likelyhood, working pressures listed might be several times less than failure pressure, so I should not have worried about it.

As it is, I did a bad and dangerous thing anyways; by mixing differing brands of hose, fittings, and crimper. If you happen to look out to the west and see a mushroom cloud coming from my direction, you'll know the hose, end, & crimper suppliers were right and I was wrong.