Looking for critiques/advice on my home air setup

M

MWC

I am pretty close to having finished my home air setup. My compressor is a 5 hp, two stage, 60 gallon unit that puts out 15.8 cfm at 90 psi, and I've run 50' of 3/4" copper line from the compressor. It's hard to tell in the picture but the lines are tilted toward the right a few degrees so the water will either run into the two drop lines or back to the compressor where I can drain the water from the bottom of the tank. I still need to install the filter/regulator assembly and the lead-in line, but I drew the former into this photo for reference. I am going to run a water separator -> regulator -> motorguard m60 filter and then a 50 ft 3/8" hose with high flow fittings to a Devilbiss FLG-4 I will be using for primer, base, and clear.

My biggest question is whether or not this setup can cool the air enough to paint a whole car. I had seen guidelines that specified a minimum of 25' of tubing and even though I've run 50' I'd still like to hear some opinions.
 

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I have the same compression and setup a heat exchange that uses an oil cooler attached to the cage around the drive belt. Not the same setup as you but using a cheap temperature meter https://www.amazon.com/Etekcity-Las...id=1548085910&sr=1-3&keywords=temperature+gun I can measure the temp of the lines going into and out of the oil cooler. Out of the cooler I typically measure ambient temp, so I know the oil cooler is working real well. You can do the same to the copper lines you've installed. I would have the copper lines you've installed run BETWEEN the pump head and the tank. If you need more cooling, setup a cheap box fan to blow air over the copper lines to get more heat transferred out of the air in the lines.
 
I'm not understanding your cooling grid. Appears to have parallel piping as opposed to a series, I.E. in one end and out the other. I think the air will follow the least line of resistance and with the tees your not getting the full cooling benefit from the total length of tubing.
 
The piping is in series, it just goes back and forth along the wall to save space. The drop lines are placed such that the bottom line can drain back into the compressor, the two above that into the first drop, and the two at the top into the second drop. I've updated the picture with red arrows showing the route the air takes and blue ones to show the drains.
 

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OK I see the circuit now. I got the part about it all pitching back toward the compressor. Your going to connect those 2 drops (blue) back to the compressor? If yes then why?
 
Geez sorry for the continued confusion. When I said the bottom line I meant that the lowest row will just drain back into the compressor. The two rows above are drained by the left of the two drop lines with the blue arrow, and the top two rows are drained by the right of the two drop lines with a blue arrow. These two drop lines just have ball valves at the bottoms and will remain closed when I'm using the air, only serving as drains to empty the lines of collected water after use. They will not be connected to the compressor. Hopefully that's clearer.
 
;) Now with that cleared up back to your biggest question, "will it be enough to cool the air while painting an entire car". The 50' of 3/4" pipe is certainly going to help. The suggestion of using a fan over the pipes isn't a bad idea either, I didn't because of where my pipes are. The moisture problems seem to be the worst in high temperatures and high humidity. I have closer to 75' of 1/2" copper including a cooling grid between my compressor and the painting regulator. In addition to a water trap, oil/water separators (3), a .01 micron coalescing filter and 10lbs of desiccant. It worked but the desiccant, which is at the end of the line before the paint hose regulator, didn't last as long as I would have liked. I since spliced in a refrigerated dryer and run it when I paint. It was worth the cost and time.
That said, where you draw the line depends on how much painting you plan to do, how much time and money you want to put into it. The only thing I might recommend is in addition to your water separator, add a good coalescing .01 micron oil/water unit. Then keep a spare filter on hand for the Motorgard.
Then try it out. I know guys with less are getting away with it (or so they tell me).
Edit to add: I wasn't familiar with that M60 and since looked it up. The add I found listed it as a coalescing filter so you have that covered. I would still want a spare filter so if it gets saturated in the middle of painting you can finish.
 
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Good idea to get a spare filter, I'll have to make sure I order one.

At this point I'm getting exasperated trying to figure this out. I feel like I've been reading things for weeks and not getting anywhere. It looks like what I've made now would be ideal if I was going to add a HF air dryer at the end, but I really don't want to spend the extra 400 given my budget for this project. I am going to have to do some blasting and some practice-painting on throw away panels because this is my first time painting anything. Hopefully I should be able to get an idea if what I have now is sufficient by that point. I was really pretty hyped on what I built so far but am now second guessing myself and it's kind of taking the fun out of it a little bit.
 
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Where are you located? Are you in Florida, or Maine. If your compressor is drawing cool dry air, you may not need remove that much moisture in the first place. Or, you could plum the inlet to the compressor to draw from a cool dry place. You may be overthinking it, sounds like myself. Finish your piping and do some test panels and see how it goes. I've painted a whole car with that compressor without any air cooling with no problems. I just wanted the added insurance especially during the humid summer months. I'm in NJ.
 
I'm located in CT, not to far from where you are in NJ, and I'm going to be painting the car this winter so at least that will work to my advantage. If anything I'm going to have to really make sure the car stays above 60° when I'm painting. I ordered the remainder of what I need to get what I've made so far up and running so I'll see how it goes.
 
I say run it. It's not like you going to do production, all day, every day painting. And your compressor looks brand new so not going to piss oil like the antique I'm using.
I'm in CT also, near New Haven. Let me know if I can help out somehow.
 
I doubt very much that you are going to have a problem. The hotter your compressor gets from continuous running, the greater your chances of moisture in the line. Maybe the easiest thing to do would be to think of ways to limit the compressor run time.

Add air storage
Build pressure a half hour or so before spraying
Spay smaller batches, if possible.
You could also make a cat litter filter.
 
I'm not bashing your idea so don't take it that way, but you have effectively robbed the entire wall of being able to use it for other purposes. The idea of an effective cooler design is to disrupt the air flow as much as possible by using turns and redirecting the air in another direction, effectively smashing the water/oil & heat against the inside wall of the cool wall piping where it can collect and be driven out by the rushing air flow. Your long runs are not necessary and will be not as effective as a much smaller unit with alot of bends. Only the air the touches the inside cool wall pipe will be cooled and the center of the air-flow (think of it like a solid piece of wire inside there) will still be hot for a longer period of time. The other thing is that piping could get hot to the touch you need air flow to cool the piping like a fan to dissipate the heat. I have 2 professional fan cooled aftercoolers (that I no longer use) that are designed to be mounted between the compressor head and the tank and that air temp can reach 350deg and these units cool that air down to ambient temp before entering the tank. These units are roughly 2-2.5in thick and 1ftx1ft square, that's it, they are designed like the condenser I your car with many bends that redirect airflow and have cooling fins like a condenser does, the fan pulls cool air thru the fins to remove the heat from the pipes otherwise it is nowhere near as effective at cooling the air in the piping.

When you have a built in aftercooler that comes with some air compressors they use the large pulley (which is also a fan blade to draw air across the pump) to draw cool air thru the cooler fins to cool the air.
 
On my 25 cfm 175lb setup, I made a aftercooler coming off the head using 3/4 copper pipe runs about 18 inches long for 7 back and forths then running into the side of a T and plumbing the air to the tank off of the top of the T and the bottom going to a drain with a ball valve. The cooler is hung on the fan side of the pulley cage. I used elbows and street elbows to make the returns on the cooler. A lot of soldering but turned out well. Also had to adapt 3/4 AC copper to 3/4 plumbing copper..
 
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