Water separator for painting?

[Gerry]

Finally getting close to painting my cab. Never painted before and my first question is what do I need to put on my compressor for moisture?
Thanks,

[WarrenD]

Depends on the type of your compressor, but you may need an oil seperator as well.

[Carter]

You should install some kind of air filter/moisture separator preferably several feet from the compressor outlet to allow moisture in the air to condense in the line to the filter for easy removal. This is one I bought at Harbor Freight that works well and cost about $35 IIRC. In this shot you can see that I also have an oiler installed for my air tools.

[nortonscustoms]

I would also highly recommend using an inline disposable filter. Any paint supply shop or decent Napa will have them.


http://www.tptools.com/p/2504,69_Econom ... lters.html

[Gerry]

I have a water separator similar to yours but I still seem to get some moisture. Will disposable filters remove whats left or will i need something else.
Thanks,

[Carter]

Have never needed to use them so I don't know how much moisture they will remove.

[nortonscustoms]

Gerry,
I worked in my uncle's body shop for a few years and he had a full commercial/industrial water and oil filter setup plus a chiller. I was always shocked at how much water and crap were in the disposable filters when we would change the out. They really do work. Painting an M37 a basic filter/water separator and a disposable should be all you would ever need.

[Gerry]

Thanks all for the info

[MSeriesRebuild]

All you would ever need for an M37??

Not in our case it wouldn't. The end product you desire, your location, and the humidity in your area holds the answer to your original question. If the air where you are is relatively dry, minimal equipment may work decent. If it is so humid you can cut it with a knife like it is here during the summer, all you can get may still be nearing border line. I won't go through all we have in our system as I feel sure you aren't interested in making that sort of an investment. The bottom line is very simple, moisture in your air lines when painting will screw up any paint job, regardless of the type of paint you are using. It has an even worse effect on the later high end paints, so pay close attention to the supplied data and instruction sheets that come with any good quality paint from a reputable supplier. Moisture's effect on that product will be discussed.

I simply don't understand the statement about minimal equipment being all you will ever need in the case of painting an M37. A good quality job, whether it's going on a rusty wheel barrow, an M37, or the finest rare Mercedes really doesn't matter. You need to equip your system with what is needed for your particular situation and climatic conditions based on all the relevant facts to achieve a nice quality end product.

[Josh]

Agreed with Charles. I built my own separator, and it has two purposes, to remove water, and heat. Heat can screw with a paint job too. This is not mine, but, mine is very similar.

http://media.photobucket.com/image/copp ... -traps.jpg

Mine cost me about $150 to build, which some might consider over the top, but I didnt have any issues with water, and the air was nice and cool by the time it got to the hose. I didnt have any issues with my sand clumping or sticking either as I was sandblasting. I ran the sand through over and over without stopping, and other than the occasional bit of dirt plugging the tip, it saved me from the frustration of drying my sandblasting sand as well. For belt an suspenders, I put a $50 dirt and water trap at the end of my copperer one. Very little moisture made it to that one, and what did was usually because my copper one had filled faster than I expected. Some guys put a fan behind them between the studs of the wall, pulling in fresh air from outside to blow over it for more condensating ability. Removing the heat helps condense the water faster. Remove the heat, you remove the water.

After spending a month and a half doing body work, and $1500 on paint supplies, the $200 investment in a quality air feed was worth it.

Oh, one more thing. Buy a new hose for painting. Dont use it for DA's, air tools, or anything else. Just the paint gun. That will help keep oil from the tools (or your built in oiler, if you have one) from contaminating your paint.

[Gerry]

Thanks Charles and Josh. I am planning on using GILLESPIE paint. The separator looks easy to build. Too bad copper prices went through the roof. I thought about running my air hose coiled up in a garbage can of cool water before my separator. Do you think this might work?
Thanks,

[Josh]

Gerry,

I understand where you're going with it, but, the issue with that is that the hose does not have a drop leg to take the moisture out of the path of the air. The moisture will get carried to the end of the hose and into whatever equipment the hose is connected to. If you look at the picture I posted carefully you'll see he has drop legs on his at the low points to act as catch traps for the water. I had mine set up the same way and my only regret was not making them longer so they had more capacity.

Josh

[Gerry]

Josh,
My thought was to go to my separator after the cooled hose. I did notice the drop legs on the picture and I will take your advice and make them longer.
Thanks

[Wayne64]

OK, here is my take on shooting enamel on my M37. Unlike Charles I'm retired and can wait for good spraying conditions. I go to the NOAA weather site and get the accurate humidity, temp, and dew point from around 8 miles away at a local airport. My gun has the cheap HF disposable water filter. I won't fire up the gun unless the I see the following. Humidity less than 40%, Temp over 65 degrees, and dew point will have a 15 degree spread or more. Dedicated hose and when the conditions are right I do a total blow down on the compressor first (so I'm only pulling dry air). I also follow these same rules for all body work, be it primer or body plastic.

As you can see by the link I'm not painting today

http://forecast.weather.gov/MapClick.ph ... n=-73.5131

[MSeriesRebuild]

This is great if it works where you are. We might paint a day or 2 a year under those circumstances, so obviously, we have to do something different. It is best in our area if you are painting in an air conditioned facility because of the dehumidification effect. You could cut it with a knife at 6 AM this morning when I went on my morning walk to the river and back. I try to do this walk twice a day, this afternnon when I went on the second trip; heat index was 105*. It's just something you get used to and learn to deal with.