Compressor question.

MTboatguy

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I know this might sound kind of odd, I am putting a new regulator and water filter on the out put of my shop compressor, but was just wondering, has anybody every figured out a water filter system that can be put on the input side of the compressor, so that you can filter the water out of the air going into the compressor tank? In theory it does not seem like it would be that difficult to filter the incoming air?

Guess what I am asking, because I have never seen one, does anyone make a pre-filter for water?

And I see, I posted this in the wrong section, please move to non boat tech.
 
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tpenfield

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Might have to compress and throttle the air to release the moisture. . . So it may be a compressor before the compressor :noidea:
 

thumpar

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I don't know that it is possible since the water is produced when the air is compressed. You would have to put some kind of dehumidifier system on it before it enters the compressor.
 

nwcove

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Might have to compress and throttle the air to release the moisture. . . So it may be a compressor before the compressor :noidea:

i think that would be the only way to do it also, but might defeat the purpose of keeping water out of a tank, as the first compressor will have water. (the compact refrigerated dryers that go on the output work great tho !!)
 

MTboatguy

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Thanks guys, I was just sitting here with to much idle time on my hands and got this brilliant idea! LOL if you have to drain it and filter it coming out, why not a system to get rid of it before it goes in!

Seemed logical, but as I told my wife, my name is not Spock!

:lol:
 

gm280

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Okay here are a few facts about compressors and water issues. We all learned that water can't be compressed in science classes is school. And since water can't be compressed, when your compressor compresses the air, some water falls out...because it can't be compressed. And that water that falls out of the air, collects in the tank. So when you have a high relative humidity day, the water will collect fast in any compressor as well. And since the compressor seriously heats up because of the compression factor, it can carry more moisture as well. Installing a water trap at the output will collect some of the water from the supplied air, but not all of it because while the air is hot from compressing, it can still carry with it a lot of water mixed in. And as the air/water travels down the air hose, it cools off some and therefore the water condenses in the hose as well. So the absolute best place for a water trap is right at the air tool attached to the very end of the hose. But some times that just doesn't work. And that IS the reason we have so much problems with moist air in the lines all the time. Some large factories actually use dryers in their systems to really dry the air supplies. And they work very well. But the average home owner seriously can't setup such expensive and large dryer systems. So we have to drain the tanks regularly and use water traps, especially if spray painting anything... Regular air powered tools really need daily oiling to save the internals from such moisture and rust taking over... :thumb:
 

nwcove

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Okay here are a few facts about compressors and water issues. We all learned that water can't be compressed in science classes is school. And since water can't be compressed, when your compressor compresses the air, some water falls out...because it can't be compressed. And that water that falls out of the air, collects in the tank. So when you have a high relative humidity day, the water will collect fast in any compressor as well. And since the compressor seriously heats up because of the compression factor, it can carry more moisture as well. Installing a water trap at the output will collect some of the water from the supplied air, but not all of it because while the air is hot from compressing, it can still carry with it a lot of water mixed in. And as the air/water travels down the air hose, it cools off some and therefore the water condenses in the hose as well. So the absolute best place for a water trap is right at the air tool attached to the very end of the hose. But some times that just doesn't work. And that IS the reason we have so much problems with moist air in the lines all the time. Some large factories actually use dryers in their systems to really dry the air supplies. And they work very well. But the average home owner seriously can't setup such expensive and large dryer systems. So we have to drain the tanks regularly and use water traps, especially if spray painting anything... Regular air powered tools really need daily oiling to save the internals from such moisture and rust taking over... :thumb:

refrigerated air dryers arent just for large factories, "relatively" inexpensive and compact units are available, they do work well. maybe not for an option for the average guy out in his shop, but if you have high end tools, do some painting and or media blasting, its worth looking into. i would guess for less than the cost of a good shop compressor, an air dryer could be added.
 

bruceb58

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Don't put the water separator at the output of the compressor. It won't do much at all there. Actually a waste of time putting one at the exact output of a compressor. Most of the water will actually just condense in the tank as the air cools in the tank. Needs to be at the end of a line which allows the air to cool. That is also where your regulator should be as well.

You drain your tank at the end of every day? If not, get into the habit of doing that or get one of those automatic drain valves.
 
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bruceb58

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We all learned that water can't be compressed in science classes is school. And since water can't be compressed, when your compressor compresses the air, some water falls out...because it can't be compressed.
That's actually not how it works. Has to do with vapor pressures, dew points, saturation points and temperatures.
 

MTboatguy

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You drain your tank at the end of every day? If not, get into the habit of doing that or get one of those automatic drain valves.

I already have a automatic drain valve. I really don't have much problem with water, we run at low humidity most of the time around here, as I said, I had idle time today and was over thinking while I waited for the rain to stop.
 
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MTboatguy

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You guys that have run air lines in your shop, what are you using? I have used schedule 40 PVC for a few years now, but have read some horror stories about PVC, are you running galvanize pipe for your systems?
 

MTboatguy

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Thanks Bruce, I was also reading about using PEX for air and it seems it is getting some good reviews, I have tons of that stuff around here after re doing my house over the years, if it does blow, it does not put out the shrapnel that PVC does. Right now, I just plug my shop hose into the side of the air tank and pull it around, but I would like to do three drops, one to the front of the garage, one to my walled off back shop and one to the side of my shop where I normally work on cars and I will most likely pick up three air filer regulator combos so I can adjust air pressure at each hook up port, two of them will have automatic oilers in them and one will not so I can use it for painting.

Just in the planning phase and don't want to drag those long ass heavy hoses around anymore.
 

MTboatguy

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Is it acceptable to put the air regulator right on the tank like they do in portable systems and then put the water filter down line away from the output to allow the air to cool and be caught by the water filter? In not, Why not?

Thanks.
 
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bruceb58

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Depends. How accurate do you need your air pressure? Do you care if the pressure drops through the rest of the line?

When I use to paint cars, it was very important as different air pressure changed how light the color would be.

Some air tools like to have more air pressure so you will have to compensate for the pressure drop.
 

gm280

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Is it acceptable to put the air regulator right on the tank like they do in portable systems and then put the water filter down line away from the output to allow the air to cool and be caught by the water filter? In not, Why not?

Thanks.

Actually you can install a pressure regulator any place you like. But if you install a regulator at the tank and set it for say 40PSI, I can guarantee you there won't be 40 PSI at the end of the hose when air is flowing. The hose acts like a resister and drops the pressure the further the length of the hose. When I set up my paint gun to spray paint, I will set the tank regulator at about 75PSI and then I use a small regulator at the gun and set it for 35PSI. And the reason for doing that is because the manufacture stated that 35PSI at the inlet of the HVLP gun will yield 10PSI at the tip. And by EPA law, that is the max any paint gun is allowed to spray these days. Now I realize I'm not a body shop, but since the guns were designed to operate at that pressure, I use the same setup. My PPG auto paint dealer actually told me that the EPA does walk in checks at the body shops. And if any gun has more then 35PSI at the gun or more then 10PSI at the gun's tip, they are closed down and fined. And she also told me that as a hobbyist, I can legally only paint three cars a year without EPA issues. If caught doing more, I too can get fined... Not sure how they would know though. Just passing on interesting info. :noidea:
 

MTboatguy

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Thank you gm, I am once again back in a learning phase as I try to reorganize the shop for a couple of different things, I do a lot of wood working, and want to keep that in the front shop, but I also end up doing a lot of wrenching which as I asked the other day on organization. But I need to have air in three different places, two of them will have automatic oiler's and I am going to run a dry line for painting, so am just getting ideas of what others have been doing.

Thanks again.
 

bruceb58

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I have some finish nail guns that don't need(actually can't have) oil. Keep that in mind when you are doing your oilers. I just oil my other tools before I use them.
 

MTboatguy

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I have some finish nail guns that don't need(actually can't have) oil. Keep that in mind when you are doing your oilers. I just oil my other tools before I use them.

The majority of the tools I use in the shop, require tool oil, the only thing that don't is the paint guns, the rest need to be oiled.

I use my staplers and finish nailer with my little pancake compressor when I am working in the house, they don't require oil. I have never used my woodworking air tools in the shop, I build everything in place in the house.
 
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