garage air distribution/DIY

[95PGTTech]

key question: can I run two smaller air compressors in tandem (safely, and effectively)?

I currently run one craftsman 33 gal 2 hp/6hp max 110v compressor (6.4scfm at 90psi) and am upgrading the garage over winter with an air distribution system. I am using 1/2" pex tubing rated for the pressure with sharkbite fittings. nothing elaborate, just one connection at every corner so I can stop wheeling the compressor around.

I have no room to upgrade to a larger (physical size) compressor and I do not have provision for 220v wiring, both the easiest ways to go bigger compressor. I feel my air tools are mostly underpowered as it is. I am using the standard 25 foot 3/8" line that came with the original kit.

I do have enough room that I can move some stuff around and run a second identical compressor next to it. they are very easy to find cheap since there are so many of them out there. Could I make a T-fitting coming right out of the two compressors and run them essentially in tandem, sort of like dual fuel pumps? I would put the regulator after the T fitting but this makes me think flow wise I would now have 6.4+6.4 (a little less for losses) of flow and make the tools work a lot better.

The outlet that I am using now for only the one compressor is rated for 30amps and is GFI so I'm covered there. I will probably finally get around to running a 220v line into the garage when it gets warmer for the spring upgrade (also insulated doors and a garage door opener on the 2nd door I only have 1). I have an oven for powdercoating and I'd like to upgrade the welder so it seems that would be the optimal time to go 220v compressor but will this get me by for now?

 

[oldmodman]

No problem.

A friend of mine decided to move both his compressors to a small outbuilding to keep the noise out of his shop.
They are both 220 volt units. One will pump up to 225psi and the other 175 psi. He wired them so that when the 175psi one shuts off it trips a relay and shut off the other. 175psi is plenty for his needs. The air goes into a dryer from the compressors, then into a 600 gallon storage tank. Then into plain old water pipe he has running around his shop.

His system works great with all his air tools and supplying air to his machining equipment. Where it is lacking is when the blasting cabinet is being used. It sucks up so much air volume that some times you have to stop and let the compressors catch up.

 

[Digital]

Shouldn't be a problem. I've ran a few air systems in automotive and assembly shops and they had 3-4 compressors feeding a storage tank that were on a relay system and the air came from the tank to all the bays and then to the various outlets.

 

[95PGTTech]

Just to clarify guys I don't have and no space for a storage tank. I realize that would be a big help for my setup but no space. Looked at all the normal garage journals etc seems what I want to do is ok and cost effective

One concern I had is start up draw (current). Any tips on how to wire relays or set up regulators so they never cut on the same time

 

[dynasty_v6]

I think you mean in parallel? In tandem, would mean you're feeding 1 into another?

 

[95PGTTech]

I think you mean in parallel? In tandem, would mean you're feeding 1 into another?

Correct. I was thinking "parallel" would be similar to electrical. What I mean is to run the "oem" air/water filter directly off each compressor/tank and a soft line to the wall, where they would T. a regulator at this point, and then the 1/2" pex distribution. at each end is the normal household 1/4" air tool fittings/soft hose (sorry I said 3/8 before).

more and more I'm seeing this is common as I can pick up a second compressor for around $150 versus a couple thousand to upgrade to 220v by the time it's all said and done. where I'm still wondering now is what diameter tubing I should be using for the distribution (garage measures 30x30) and how to run the air/waters, regulators, and electrical so both never cut on at the same time. everywhere I see keeps saying a $40 roll of 1/2" pex tubing and home depot sharkbite pushlock fittings but that doesn't seem to add up with the "oem" 1/4" fittings?

 

[Torrance]

Do you have space in your rafters? Source some large diameter pipe and make your own "storage".

A friend of mine fell into a nice cache of SCH80, 3" PVC that he plumbed in his rafters for storage, because he doesn't have the room for a big tank.

 

[STAMPEDE3]

2 30gals will give you 60 total. Should be enough for most projects.

If you are useing the compressors I think you are then much more tank capacity than that and you may burn the damm things up trying to fill it. lol

You should be fine with what you are trying to do.
1/2 in is a minimum I would use as far as the distribution tube.

5/8 is better and 3/4 would be fantastic. Then drop the size down at each connection.