View Full Version : Air compresser problems...

V.A Melle
08-28-2006, 7:43 AM
Okay I know you guys are gonna scare me again:) but I'm having issues with my air compresser. I think where I live is to damp and when I run the air compresser I get drips of water on my boards-what is up with that? How can I stop this from happening? do I need a fan or something? dehumidifier? what now?

Joe Pelonio
08-28-2006, 8:12 AM
You should have an in-line water filter where the hose to the laser connects to the compressor. Just $20 or less at home centers.
In addition, use a long hose and have a couple of loops in it, any water will stay at the bottom of the loop. Not only don't you want water on your material, but it can rust the metal air tube/nozzle.

Dave Jones
08-28-2006, 10:20 AM
What kind of compressor are you using?

I found that with my cheap airbrush compressor, even though it has a water filter/trap, if I run it a long time the head of the pump heats up too much and water starts coming out the air hose in the laser. I guess it's from the big temperature change along the way through the hoses. So now I just turn it on while it's really needed and immediately turn it off when the laser stops. If I was running the machine continuously for hours I think I'd have to go get one of the manufacturer compressors instead of this $50 airbrush compressor from Harbor Freight.

John Esberg
08-28-2006, 11:31 AM
Hello V.A. Melle,

The advice on the water trap is dead on the money correct. It should be the first item on your list. If you use the type that Joe showed us, just be sure you have it vertically mounted.

As for how your air lines should be setup, the correct way is direct path as much as possible from your compressor to your filter(s) to your laser (no offense Joe). There are a couple of reasons why you should set it up like this:

1. Minimize headloss. (In simple terms, the longer the line the more energy wasted.)
2. Minimize possibility of biologics forming. (This is something you usually won't even find being discussed in engineering schools. After 10 years of working in nuclear power plants, you would be surprised how many times I've found small germs eating our equipment. Strange but true.)
3. Low point curves & loops lead to waterhammer where low point drains are not installed. (Since you are using low pressure air, you most likely won't have too strong of a slug of water developing. But frankly, why take the risk on our sensitive equipment.)

You also mentioned a dehumidifier. If you live in Hawaii like I remember, I wouldn't. You could certainly do it, but I'd just go with a water trap on the downstream side of an air compressor. Less equipment, less engineering, and probably less energy consumption to boot.

Well, I hope that helps.


Bart Leetch
08-28-2006, 11:46 AM
You probably already are but I thought I'd ask anyway. Are you draining you compressor tank at least once daily or more often? When I was a sheet metal apprentice this was part of my daily routine as I opened the shop for the day. This & water traps & sloping you air line so that the water runs back to a low point drain should take care of the problem.

tod evans
08-28-2006, 12:39 PM
"v", take a few min. to read this, it`ll help explain how folks deal with moisture in airlines.....02 tod