i just bought a moisture/oil seperator from the local paint shop its made by finishline and ran me like 120 bucks .... now i see one at harbor freight for less than half that price...
i plan on painting a few times this summer, anyone have problems with the harbor freight unit? and how long can i expect these to last if i remove them after each job??please help thanks neil

I have a general opinion on Harbor Freight based on having a lot of their tools in my colection. They are good but NOT great. They are mostly Chineese copies of good American brands. The problems show up in cheaper materials and sloppier tolerances. For occasional use, they are OK but won't stand up to heavy professional use. Somewhere down in this section, I did a side by side comparison of a HF HVLP and a Sharpe Cobalt. The HF works pretty good with properly mixed, high quality paint. The Sharpe works better even with that cheap eBay paint. A filter doesn't move much so it should last OK. I'm sometimes a little bit of a tool snob but, if I'd already bought the good one, I'd keep it and be happy knowing that wasn't going to be the weak link in my system. Better tools leave the operator a little more room for miscues.

BJ is completely accurate HOWEVER, IMHO for the occasional diy painter I think its overkill!

For those of us who plan on painting only a few times/yr I think some of the HF products are more than good enough. If ur looking for clean(er) and dry(er) air Id look into this item> http://www.harborfreight.com/cpi/ctaf/Displayitem.taf?itemnumber=1118......Ive read from several forum members that it works real good.

I've got one and it works well.

What can I say. I've got one of those sitting beside my compressor right now as a replacement for the antique that's on it. For $20, you can't go far wrong. I thought for some time that the HF one was an unusual design. I was thumbing through a Sharpe catalog a little while back and discovered where the design originated. They are a copy of a Sharpe unit at less than 1/5 the price while they are on sale.

Big Jim wrote:What can I say. I've got one of those sitting beside my compressor right now.

I hope there is also a nice big pile of hose lying between your compressor and that separator or it won't do a darn thing. Air needs time to cool so the water will condense.
Personally I'm still just getting set up and I bought a Sharpe water separator and ran 50' of hose from the compressor to it (I know, not ideal all that small hose between compressor and tools). Just running d/a and sandblasting I couldn't believe the water I got out of it--and some of that was when temps were barely above freezing and the intake air was pretty dry. I can't wait to see what it collects in the summer...

Hows just 50' of hose between ur compressor and water separator helping matters?
Do you have a drain set up somehow in between?
Wheres that condensed water go?

just curious

If the air is still really hot, the water will still be in the vapor stage and will tend to go right past a filter. When it leaves your gun, the air/water vapor mix will cool and, presto, water drops. A long hose acts a little bit as a cooler so there are already drops to filter out. The rest of the story for me is I am working on a motor home restoration right now. It does not fit in my garage so I'm using a 50' 1/2" hose to get from the compressor to the work area. I have a filter/separator mounted at the compressor and a second one set up with quick couplers that I can plug in at the end of the big line. I also have a beat-up surplus refrigerated air dryer sitting around waiting for time to be checked out and plumbed up. Luckily for me, Denver air is pretty dry. None the less, it was 93 this afternoon and, after an hour of sanding, I thought my DA was hooked up to a water hose.

Yeah, the 50' of hose just gives it more time to cool before it hits the separator. For example, if the compressor is running constant, tank air may be 150 degrees. If you give cool it to even 100 degrees it can't hold nearly as much water vapor. The long hose gives it more surface area interacting with the outside/room temp air.
Other tricks:
-run the hose through ice water (poor man's refrigerated drier) before the separator.
-use full line pressure (125# or whatever) with a remote separator/regulator. In addition to the cooling effects running through the high pressure hose, reducing the air pressure at or after the separator allows any remaining moisture to re-vaporize (air at lower pressure can hold more water than the same air at higher pressure).

Matt T wrote:reducing the air pressure at or after the separator allows any remaining moisture to re-vaporize (air at lower pressure can hold more water than the same air at higher pressure).

I might be wrong, but I thought it was the other way around. For instance, low barometric atmosphere pressure is usually associated with rain and high atmospheric pressure with sunny weather.

Could someone verify this one way or the other? Thanks, TomBk