Shop compressor air dryer for DIY resto projects

I'll relate my experience with trying too hard to DIY and not just simply spending the money on proper equipment. Quite a while back I stripped my 66 Mustang down to bare metal. Like you I wanted to control moisture, but instead of buying suitable equipment I searched around and built my own desiccant based drier. After shooting two coats of epoxy on the car I noticed small "bumps", after to talking with everyone here it looked to be bits of that desiccant I used. So yeah, I had to strip off all the epoxy and went back down to bare metal and shot the car again with two more coats without the DIY rig. Hmmmm how much money did I save?
 
On the other hand, if you found a used refrigerated dryer, you could probably sell it for what you paid for it when you're done. With a homebuilt copper / filter setup, they're pretty much worthless when you're done.

Exactly! Not to mention it would take about an hour to plumb and plug it in and your off to the races with no worries.
On my set up I have my compressor on 80 gal tank outside under an awning then its plumbed through the wall and goes about 15 ft to a second 80 gal tank. from there it goes to a motor guard m800 system (which is a oil coalescing filter, a particulate filter and regulator good up to 120 cfm). I have that regulator set to 120 psi. after that regulator there is where my refrigerated air dryer is located. By having the dryer so far from the compressor and after 2 tanks I have already pulled a lot of moisture out of the air which allows the dryer to be that much more efficient. after the dryer the line splits one feeding my booth which still has a sharpe desiccant system hooked up but really doesn't do much any more, I just leave as a just in case. The other line feeds the front of my shop where I need air for air tools.

you should have the dryer 1st after the tank. That is what is is designed for.
 
Ok ok, you guys all make good points. I had another thought. What if I coiled up 50' 3/4" copper line, put it in a bucket of water, froze the bucket before painting or sanding, and then put it in line with my system. After the bucket would be a dip and a drain. From there would be the HF refrigerated drier. From there would be an m60 filter and finally my regulator.

Does that sound like a solid, done right setup? Is it enough filtration for oil? Again, as someone mentioned, I have a single stage compressor where oil may be more of an issue.

Yes, I like to explore the cheapest option, but I am NEVER against spending lots of money if it's the only way to do it right and purchase peace of mind.

do all that and including he cost of material you are so close to what I have been telling you, you might as well cave in and get and do what I said.

There are other makers of the unit I said, even though they were probably made by Hankison. Just make sure you get no less then 20cfm, HIT.
 
Yes, datec, after all your guys' help I have realized that this, like many other things, can't be avoided. If you want professional results you have to get the professional equipment.

I think I'll just get a HF drier and do exactly what I've outlined above. Do I need the ice bucket before the HF drier? the HF site says it brings the dew point to 36F. Is this low enough HF? i thought I've seen other units that bring it down to -80F.

Could you guys address the oil issue? Do I need all this stuff we've been talking about along with a DAD500 or other 5 stage filter system like what was posted earlier in the thread? Can I use one of these 5 stage systems alone and forget all this stuff we've talked about this far, or am I going to have to cook the air with a refrigerated system no matter what i do with filtration?
 
MX442, I like your method. Any idea on how much cash you got in your setup? I'm guessing the m60 is the most expensive portion of your investment, and they're only like $75. I have higher humidities (at times) than you being as I'm in NW Ohio. If you have such good luck, maybe I just need to go that way. It seems like the guys who have made similar setups all have very good luck without taking the refrigerated route.

DATEC, the $450 unit I see on eBay right now has all kinds of disclaimers on it and caveats along with extensive warnings that he doesn't take returns and hasn't tested the united. The listing doesn't give me a warm feeling. I will have to pass on it, but I really appreciate you teaching me about a good brand to look out for!

My compressor may not be a professional grade unit, but it should feed my iWata LPH400 which requires 9.5CFM at 29psi if I remember right. I do have horrible moisture problems though. After the compressor runs awhile I get TONS of water spraying out my die grinders and other tools. I've been ready to paint some parts in epoxy for a couple weeks now and have had to find other things to do on my project, because I am aware of this water issue and haven't decided how to address it. I don't know how important it is to have perfectly clean epoxy, especially since what I'm painting are interior panels that are only binge rust-proofed, but I figured I may as well do all of it "the right way."

I kick all these ideas around and typically I just end up flipping a coin of sorts and just picking one. I think I'm gonna go the cheaper route with this. It seems this route gets the same results as going the expensive route, and yes, I may do another car....in 15 years. The need for perfectly clean air is NOT typical for me. I am a farmer and use the air all the time, and while clean, dry air is great to have, I don't NEED it EVER. This project is the only time I have been sand blasting and painting quality paint. So if I can get away by doing this clean, dry air setup at a DIY budget, I think I'd be best off.

With all that said, since you guys have pointed out that I may have additional oil problems with a single stage compressor, would it be in my best interest to invest in two m60 filters? I could have one right out of the compressor. Next the line would go through a condenser or small trans cooler. I'll probably set up a fan to blow over this. From the trans cooler I'll run the air through 20'-30' of coiled up copper tube in a 5 gallon bucket of water. Out of the bucket of water and coiled copper tube I'll run into an expansion/ dryer tank. This tank will just be an old portable compressed air tank I have laying around. This tank will have the water drain on it. It will be a manual drain if I have this whole system setup on a bypass leg for times when I need the super clean and super dry air, and it will be on an electronic, auto valve if I decide to leave the whole system permenant as part of my day to day setup. From here I'll go into the actual compressor 60 gal tank. Out of the tank will be an additional m60 filter. After this filter the line will feed a standard regulator. Out of the regulator will be the line to my paint gun. I'm gonna keep an inline filter at the gun when I first use this setup to make sure it's working 100%. How's all that sound?

On a side note, should I remove the manual petcock drain on the bottom of my compressor tank, which I believe to be rusted shut, and replace it with an auto valve if i don't keep the whole system I described above in the normal loop and bypass the said system?
Schroeder, I don't have a professional setup, in fact my single stage compressor is smaller than yours. I'm in South Florida so it is always humid but I have clean, dry air coming out of the system. The cheapest way to reduce water at the tools or spray gun is to cool the air coming from the compressor. Just getting it to room temperature can be a huge improvement because the heated air from the compressor holds moisture like you wouldn't believe. A chiller coil used in home brewing (upside down so the water drains) might be your cheapest solution. This one is only 3/8 inch copper but you get the idea.
Copper%20Coil_zps8ycatzts.jpg

https://www.homebrewsupply.com/cold...ller-25.html?gclid=CLrVw_iEwdMCFceCfgod7NgCtw

In the beginning, I made the mistake you describe, putting an M60 filter right next to the compressor output. Within an hour the toilet paper roll is completely saturated and no longer doing anything but blocking the air flow. You want that filter at the end of at least a 50-foot metal pipe run with at least a drop leg and drain at the end of the run before the filter. If you decide to use a desiccant filter, it should also be at the end of the pipe run before the M60.

If you have an infrared temperature gun, you can verify this yourself but the pipe coming out of the my compressor head going into the tank is about 300 degrees F within minutes of starting. When that super hot air enters the cold tank, the temperature drops dramatically and basically it's raining in there until the whole tank heats up. The air coming out of my tank is around 150 degrees F after running air tools for a half hour. The water separator attached to my tank outlet has accumulated two drops of water in six years so anything besides a refrigerated dryer is useless in that spot. The 18-inch drop leg at the end of my 50-foot galvanized pipe run collects a cup of water in a typical session with the air tools (couple of hours). The $39 Harbor Freight desiccant tube next to that drop does a good job drying the air but I need to replace the screens (they've rusted).

I may have misunderstood the side note on the compressor tank petcock drain. If you can't open the petcock, you have a water tank, not an air tank. I suspect you have many gallons of water in that tank and it's the first thing I would fix. I don't have an auto drain on mine but I do drain a cup or two of water after every session.
 

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Exactly like I described but I've got the coil in a tub of water. Hot days I'll chunk a block of ice from the freezer in the tub. Crude but effective.
 
You think the water just sits in that low spot???? The pressure pushes it up and further down stream. I have a drop right after the coil with a ball valve to drain it.
 
The whole point here is the cooling separates the moisture from suspension in the air itself. Then a tee & a length of pipe dropping straight down do wonders for getting the bulk of water out before any other filtration means. The weight of the separated water causes it to fall with gravity. Simple as that.
A hint of oil may go with the water, but it pretty much takes a coalesing type filter to remove oil. Need one myself right now . Last I checked, cheaper ones were at least 80 bucks.
On a compressor tank itself, keeping it drained is as important as anything. On the 10 hp compressor at my work, I just ran an elbow & small length of galvanized pipe out to an easy to reach ball valve on the end. I can crack the ball valve just enough that the majority of the time I can have water bubbling out of it without much air loss.
 
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It seems like the coaleccesing filters are way more than $80. I don't know if the motorguard m60 falls in the coaleccesing family, but it's rated to .01 microns. The best coalesccing filters I saw had the same rating. So is that all I'll need?

Compressor, copper coil in bucket, water outlet tee, HF refrigerated drier, inline electronic dump valve, m60 filter, regulator, inline filter, and finally air tool. Yay or nay?
 
Compressor, copper coil in bucket, water outlet tee, HF refrigerated drier, inline electronic dump valve, m60 filter, regulator, inline filter, and finally air tool. Yay or nay?
Chilling the air in the copper coil and then running it through the refrigerated drier is somewhat redundant. I would say
EITHER:
Compressor, copper coil in bucket, water outlet tee, m60 filter, regulator, inline [desiccant snake] filter, and finally air tool.
OR
Compressor, HF refrigerated drier, m60 filter, regulator, and finally air tool.

That copper coil alone (no ice bath) and water outlet tee will help remove a significant amount of water from your air supply. Probably enough for running your air tools without water (or ice) forming at the tool outlet. I would fill the bucket with ice and use the desiccant snake for painting as the belt/suspender approach.

On the other hand, the refrigerated drier is all you need to dry the air completely and you shouldn't need the desiccant snake.

I have used those globe-shaped desiccant/filters a couple of times but they are a joke in Florida. I open the package (breaking the seal), screw it on to the end of the hose, screw the spray gun onto the filter and the media has changed from pink to blue. That's before I turn on the air or pull the trigger. But maybe that's just me.

[EDIT] Unless your compressor is spitting oil, the Motor Guard M60 filter is all you need to capture the oil vapor. I would recommend the slightly more expensive model with 1/2-inch inlet and outlet.
 
the m60 my remove some oil but is not a coalescing filter. the book the motor guard rep left with me shows part # co-4515 which uses 1/2 inch fittings like the m60, and the one I have #m-820 which has 3/4 inch fittings.
 
The HF unit lowers the dew point to 36F. That's not hardly low enough is it? I keep saying the copper coil needs put in after the compressor before the drier because I don't think the HF unit will take the super hot air coming in.
Schroeder, lets use the weather outside my home today to calculate what's going on. It's 80 degrees (F) with 52% relative humidity (pretty dry for Florida) which means the dew point is 61 degrees (F). That 80 degree air goes in the compressor and is heated to 150-degrees by the time it comes out of the tank. It goes in the refrigerated dryer and the air is cooled to 80 degrees again. If the dew point is 36 degrees, the relative humidity is 21%. That's some pretty dry air. Let's say the refrigerated dryer only gets the air down to 100 degrees. That 36 degree dew point means 11% relative humidity in that still warm air.

I see the dew point in Florida all the time. Coming out of a cold place like a grocery store into the hot humid outdoor weather and my sunglasses fog up. As soon as the glasses warm up higher than the dew point, the condensation goes away and I can see again. Take your glasses out of the refrigerator, go directly outside and if they fog up, the dew point is above 37 degrees. Make sense?
 
I gotta ask how old are you Schroeder? No offence is ment by my question but if you are young and strapped for cash I would fully understand you wanting to go on the cheep.

I have been doing this work for 34yrs and have been there when I was just starting out. I wish people would have guided me with what was needed because getting into this work can seem like a rabbit hole if your not guided correctly from the start (which is what we are doing). The M60 filter in my setup is the last filter before the spray guns hose, my reason is that the other filters in line with water separators will catch the crap before the final filter for the cleanest air, kinda of a last resort filter.

There can be a crazy host of designs that can be laid out for you like the desiccant filter really should have a filter before and after it. The first one catches crap before it enters the desiccant filter and a super fine filter is placed after it to catch any crap that might come out of the desiccant. We can get deeper into a design if you like, like using a twin self contained regeneration desiccant filter unit with filters before and after it but we won't go there but I assure you, you would have breathable air by the time I got done putting it together for you.

What you really need to do is not over think it you can get scrambled brain syndrome and completely loose what it is you are doing and end up getting nowhere, kinda like you are now, at least that is what I'm seeing.

No one hear will misguide you but for me I stand behind my suggestion on the HIT refrigerated air dryer I have been doing this too long and have learned too much to recommend anything else. That is your absolute best defence in getting the water out bar none. You mount it from your tank with a hi-pressure flexible air hose about 3ft long (depending on the placement distance from the tank) do not place it too far from your compressor tank because there is no need to. From there you can feed your shop with wall filters at the connections or use filters after the dryer and then feed the shop but the M60, desiccant filter etc is best placed at the point of the spraying area which should have it's own separate air hose. There is just no good reason to waste/use those on running air tools, it is just a waste of money having to refill them when they get clogged. The M60 and desiccant are considered last resort filtration to supply clean air to a spray gun for painting.
 
It seems like the coaleccesing filters are way more than $80. I don't know if the motorguard m60 falls in the coaleccesing family, but it's rated to .01 microns. The best coalesccing filters I saw had the same rating. So is that all I'll need?

Compressor, copper coil in bucket, water outlet tee, HF refrigerated drier, inline electronic dump valve, m60 filter, regulator, inline filter, and finally air tool. Yay or nay?

By the time you add all that, your little compressor will be choked down and NOT provide enough CFM to the spray gun. Like Bob said, two chillers is redundant. You are already at a disadvantage with the compressor, don't choke it down any more than you have to.

15 cfm refrigerated dryers use 3/8 OD hookups. This will really choke down the airflow. The 25 cfm dryers are 1/2 or 3/4 NPT.
Therefore, if using the HF dryer, it should be the last thing in the line of plumbing, followed by the m60. If you have 20'-30' feet of 1/2" or larger pipe leading up to the dryer, I would think it would be cool enough before entering the dryer.

I made my coil to drain from the bottom into an expansion tank. Clean air is piped out the top of the expansion tank. I keep a few 2 liter soda bottles in the freezer to drop into the water bucket if needed. You wouldn't see this setup in a pro shop, but effectively it does the same thing as a refrigerated dryer. A refrigerated dryer is a copper coil cooled by freon, followed by a water separator.

Like I said earlier, it ain't cheap. And of course you can't go wrong with Datec's recommendation, either. I have seen those dryers pop up on CL twice in the last year for about $500. I'm kicking myself for not buying one.
 
I got my son to send me a couple pics.

3/4" copper through filter/regulator. Don't laugh, the plastic bucket is lined with cardboard and foam. Acts as an intake silencer.


Air enters the coil in the top. Coil goes out the bottom of the bucket, then rubber hose to the side of the 3 gallon tank. Ball valve drain on the bottom of the tank. Dry air goes out the top of the tank, then passes through the M60 filter. Dedicated painting only hose connects after the M60. I had the hoses crimped at a local hydraulic hose supply place. I can't remember if the coil is 3/4 or 1/2. I bought it bulk by the foot, about 25'.
 
Thanks for all the help and examples. Mx442, how does yours work? Anything ever in your paint or water at your DA?

I'll do a little more research. I'm thinking about just buying one of the 5 stage filter systems like someone linked to earlier, maybe getting s copper coil, maybe an m60, and calling it good. This is definitely one of those things that can go on and on and on.
 
So far, I have only blasted and painted a truck frame. I have also run it quite a bit on a blast cabinet with good results. The M60 filter has stayed dry. Based on science and logic, I'm confident this will be adequate for a full spray. Hopefully I'm not back here to eat crow in 6 months. :) Otherwise, I'll be saving for a 25cfm refrigerated dryer.
 
Guys, I'm going to pull the trigger on his stuff his weekend and place some orders. So, is everyone in agreement that the copper coil or HF refrigerated drier will remove the moisture I need for a perfect paint job but also maintain a hobbyist budget? Is everyone in agreement that after sufficient drying through either of the above described methods all I will need is an m60 filter to remove all oil and debris? Or do I need one of these 5 stage systems as mentioned early on in this thread? https://www.amazon.com/ATD-Tools-7888-5-Stage-Desiccant/dp/B000YOSLE4

I'll make sure to get a new hose only for painting. I'm sure my current ones are full of dirt and crap.
 
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