Recommended Air Compressor for ATC

[joe_winslow]

Hello All -

Can anyone recommend a good compressor for the ATC? ShoBot is spec'ing:

7 SCFM at 100PSI of clean, dry, un-oiled compressed air at a minimum with tubing no smaller than 3/8" throughout the system (1/2” recommended).

but I am having a hard time finding one that matches these requirements.

Thank you!

[dlcw]

I bought a Home Depot 60 gallon compressor and it works fine. I had a 30 gallon and it was to small. I do have 1/2" line running from the compressor to the CNC. All my other tools run off 3/8" hose just fine.

[joe_winslow]

hey thanks Dan!

The thing that is holding me up is the 7 SCFM at 100PSI of clean, dry, un-oiled compresse notation - did you match these specs or are you running something different?

[dlcw]

I matched them up and the compressor exceeded what the ATC needs. I've been running for about 5 months with no problems. My cycle rate on the compressor, when running the CNC, is 4 minutes shut off, 1.5 minutes recharge. I do have a couple of small leaks in my air line I have to fix near the compressor, but I'm happy with the cycle rate. The ATC comes with the moisture separator, plus I have a moisture separator mounted on the compressor.

I've been able to run a Kreg air pocket whole machine along with power tools (not sanders) along with my pneumatic assembly table with no problems running the compressor out of air. Mine is 220v.

[evan]

https://www.mcmaster.com/oil-separators/ not the only source just a place to start. It's recommended (and good for all air tools) to have one down the line (far enough away form the compressor so the compressed air has a chance to cool down and the moisture to condensate) at a low point in the line.

[BoilermakerAndy]

Let's see if anyone sees this add on to an old post.

Most of the compressors I see are oil lubricated, which ShopBot says not to use. Can anyone recommend a specific compressor, preferably not $1,500.00?

[dlcw]

Let's see if anyone sees this add on to an old post.

Most of the compressors I see are oil lubricated, which ShopBot says not to use. Can anyone recommend a specific compressor, preferably not $1,500.00?

I believe, and I might be very wrong, the compressors use oil to lubricate the compressor itself. Not pump oil thru the air lines. I use an oil/water separator just in case any oil gets thru. On top of that, the water separator that came with my ATC works on oil and water. So I have two filters in line to clean the air. Been running the ATC for well over a year without any problems.

[BoilermakerAndy]

Yes, that's what I believe as well, though I imagine there is then SOME miniscule amount that makes it through to the air. Can you recommend which oil/water separator to use? Oh, and thanks for the answer.

[jTr]

I recommend you call SB for clarification. Oilers are often placed in compressed air lines for certain air tools that require a regular amount to operate, such as larger industrial machines utilizing air clamps.

My hunch says, Shopbot is making sure you do not add an automatic oiler, in case that's your habit.

un-oiled compressed air

As I read this phrase, I'm not convinced they're saying "oil-less compressor", just compressed air that has not been oiled.

My 15 year old Coleman 60 gallon compressor has oil lubed cylinders. I've sprayed hundreds of gallons of finish with simply a generic water separator at the compressor's outlet, and another cheapie in the finish room at the regulator. I've never once experienced one drop of oil or water droplets passing from the compressor. Believe me, I would know, as it would leave a very obvious problem spot in the paint or clear coats.

I'd give them a call. If my hunch is correct, a wide range of great compressors and budget options opens up.

Jeff

[jTr]

Clarification: the "cheapie" in the finish room is a micro regulator/separator from Horrible Freight.
If you want best quality, I reach for Milton brand, which is the larger initial separator at the compressor, with matching regulator.
As with Don's setup and the advice of others here, it is best practice to run a primary plus secondary, especially with sensitive equipment (like the ATC) or spraying finishes.

Jeff