compressed air dryer

[rhncue]

A question for those on here who are using compressed air to spray their finish or general air usage in the shop. Just what are you doing to eliminate moisture in their system? I'm having a fit trying to get a good finish because of all the moisture. Any ideas on a cheaper, but still effective drying technique?

Dick

 

[conetip]

I don't know of any cheap dryers Dick, sorry. The only ones that work well are expensive, but that is going back 10 years now. If there are cheaper options I am all ears as well.
Neil

 

[pescadoman]

I bought this one....
http://www.amazon.com/Sharpe-6760-D...d=1427269710&sr=1-1&keywords=sharpe+air+dryer
Of course, I also have one of these lying around that I haven't hooked up yet...
I've heard some good things about the harbor freight dryer too.

MOST dryers run all the time, so you would want to turn them off when you aren't in the shop. CYCLING air dryers work on demand and you don't have to worry about them using more energy than needed. They are also, of course, more money.

I bought mine, in what appears to be new condition, on Ebay for 400 bucks.

 

[scdiveteam]

Try 2 Desiccant filters.

One directly downstream of the receiver tank and a secondary at the both upstream of the regulator.

You can bake the particles a few times in a oven when they change color.

I buy my desiccant from MCMaster Carr.

In the winter I bake or change the pellets about once a month.

In the summer a few times per month even with the air conditioning keeping the relative humidity down.

It is easy maintenance and works very good. No moisture in the clear coat. I have two compressors in my shop and one is just for spray booth. My shop air is not dried and I blow down the tanks daily to remove accumulated moisture.

Rick

 

[rhncue]

Try 2 Desiccant filters.

One directly downstream of the receiver tank and a secondary at the both upstream of the regulator.

You can bake the particles a few times in a oven when they change color.

I buy my desiccant from MCMaster Carr.

In the winter I bake or change the pellets about once a month.

In the summer a few times per month even with the air conditioning keeping the relative humidity down.

It is easy maintenance and works very good. No moisture in the clear coat. I have two compressors in my shop and one is just for spray booth. My shop air is not dried and I blow down the tanks daily to remove accumulated moisture.

Rick

That's what I need to do. I've had my compressor since 1994 and it's only been turned off when the regulator or circuit breaker kicks out. Probably why my utilities run me 500-600 a month.

Dick

 

[rhncue]

I bought this one....
http://www.amazon.com/Sharpe-6760-D...d=1427269710&sr=1-1&keywords=sharpe+air+dryer
Of course, I also have one of these lying around that I haven't hooked up yet...
I've heard some good things about the harbor freight dryer too.

MOST dryers run all the time, so you would want to turn them off when you aren't in the shop. CYCLING air dryers work on demand and you don't have to worry about them using more energy than needed. They are also, of course, more money.

I bought mine, in what appears to be new condition, on Ebay for 400 bucks.

I was looking at this one a short time ago.

http://www.ebay.com/itm/520A-Top-Po...650?pt=LH_DefaultDomain_0&hash=item416fd6aeba

Dick

 

[rhncue]

Apparently, this one uses desiccant. Would it be better than the one that I was considering?

Dick

 

[rhncue]

At present, I'm using one of these at each airline.

http://www.harborfreight.com/air-to...es/industrial-air-filter-regulator-68247.html

Dick

 

[Bill the Cat]

No moisture option

Have you considered changing the way you apply finish instead. The problem(s) with compressed air for finishing is the the reason I opted for a HVLP system. Nothing but dry air with no oil residue. In the long run, I think it's cheaper than the expensive options to remove contaminants from the output of a standard air compressor.

 

[JoeyInCali]

http://www.ebay.com/itm/2-DISPOSABL...hash=item5b0efdf84d&item=391093549133&vxp=mtr
Put one in the gun too.
Also a compressor with a water trap helps too.
http://www.ebay.com/itm/SALE-Califo...339?pt=LH_DefaultDomain_0&hash=item4636ec30ab
I have that one. No rust in the tank after one year.

 

[cutter]

compressed air

What's the cycle time on your compressor. The more it runs the more heat cool cycle and such, more water in the air. If it doesn't run much the air in the compressor cools and the moisture settles in the tank, which you should definitely drain daily.
I have two water seperators in series. The first one does the grunt work.
I rarely have to drain the second one. The second one is about 20 ft from the first one. If you don't have that distance I would coil some air hose to let the air cool before it gets to the second one. Although doing it that way, you should purge the line to remove trapped moisture. I have water drains around the shop to keep the lines clean.
http://www.greenvalleycompressor.co...ssors/Champion-5-HP-Air-Compressor-VR5-8.html
These guys are just down the road from me and after lots of questions, this is the one we settled on. The higher pressure and larger tank makes for a very long cycle time.
My old Campbell would constantly run when gundrill. Talk about making water.
This one runs about 1 min every 8 when wide open gundrilling. Finish spraying, it may run once everty 20 minutes.

 

[pescadoman]

The thing to do is run lines from the compressor head>air cooler>refrig cooler>back to tank. You would also run sub mircon filters inline before the dryer. In that manner, virtually zero air makes it to the tank and there is little worry about the tank rusting out.

All of this is probably more expensive than a simple HVLP turbine. HOWEVER, if you need or ever plan to need clean dry air in the future for say.... ATC spindle, a spindle with an air bearing, plasma...ect...ect, then you are money ahead. Actually if you like any tool that runs on air, you will be miles ahead. The ones I listed above MUST have a clean air supply. Dry air doesn't hurt when you are blowing a piece of wood off either....

The very cheapest way to get water out is to use an automotive oil cooler or condenser with a fan. Go from the pump to cooler, then to tank. You need to plumb drops in order to drain the water, but alot of guys have very good success with them. I did alot of research, but I can't find the particular threads I was reading before.

I've seen guys use a bunch of copper coiled up vertically as well for a cooler, but that is a bit ghetto for me.

If all you are using air for is painting, I'd suggest an hvlp. Otherwise, I'd start looking at Craigslist and find the biggest compressor you can fit in your shop. The tank doesn't even have to be inside.

It takes some patience, but I've done very well in the used department. I paid 600.00 for this and it's worth every penny and more. You'd have alot of trouble finding another in this condition for hundreds more..

 

[pescadoman]

In my experience, the Harbor Freight desiccants are a waste. I don't remember what happened to the first one, but I had to replace it. Second one now leaks air constantly from the regulator. When I took the first one apart, the stuff inside looked like an elementary school paper mache project.

For reference on a couple "decent" cuemakers who use different methods.

Jerry McWorter uses a turbine HVLP.

Ariel Carmelli uses a desiccant very similar to the one I bought.

One more thing. Use hoses as little as possible and never in your main lines if running drops. If you're running direct from the compressor.....well ok, but it's always best to run copper, galv, or black pipe to your point of service and then the shortest hose possible. NEVER run PVC for airlines.

 

[cueman]

Back when I still sprayed using a compressor I hated all the water bubbles I would get from time to time. I put the glass water filters at the tank and that did not do the trick. But what helped the most was the little tennis ball size cheap disposable orange filters that attached to the gun itself.

 

[Thomas Wayne]

Back when I still sprayed using a compressor I hated all the water bubbles I would get from time to time. I put the glass water filters at the tank and that did not do the trick. But what helped the most was the little tennis ball size cheap disposable orange filters that attached to the gun itself.

Well I'm not an expert OR a genius, and I am certainly not a millionaire... but I have really expensive spindles that use air for a"positive pressure" bearing seal and also for the power draw-bar and I do NOT want to have them rebuilt just because I ran wet, dirty shop air..

So I bought one of these:

http://www.ebay.com/itm/INGERSOLL-R...660?pt=LH_DefaultDomain_0&hash=item58b6d67b6c

The bonus is I have really clean, dry air for my finish booth.

TW

 

[scdiveteam]

What's the cycle time on your compressor. The more it runs the more heat cool cycle and such, more water in the air. If it doesn't run much the air in the compressor cools and the moisture settles in the tank, which you should definitely drain daily.
I have two water seperators in series. The first one does the grunt work.
I rarely have to drain the second one. The second one is about 20 ft from the first one. If you don't have that distance I would coil some air hose to let the air cool before it gets to the second one. Although doing it that way, you should purge the line to remove trapped moisture. I have water drains around the shop to keep the lines clean.
http://www.greenvalleycompressor.co...ssors/Champion-5-HP-Air-Compressor-VR5-8.html
These guys are just down the road from me and after lots of questions, this is the one we settled on. The higher pressure and larger tank makes for a very long cycle time.
My old Campbell would constantly run when gundrill. Talk about making water.
This one runs about 1 min every 8 when wide open gundrilling. Finish spraying, it may run once everty 20 minutes.

You can also hook up an "auto drain" to the air receiver that has a timer to blow down. Some of these have adjustable timers and if you are going to be doing a lot of gun drilling you can set it for 5 mins between blow down purge cycles.

http://www.ebay.com/bhp/air-compressor-auto-drain


Mine blows down every 1/2 hour to purge water and is a very good thing that allows me not to worry about remembering to purge the tanks.

When a compressor is producing excessive water, one of the discharge valves could be stuck or restricted and the compressor can be building up excess heat because of this. This is very common thing and is the one thing that causes compressors to sh-t the bed. I had 14 compressors and I installed an in-line temperature gauge on the discharge pipes coming from the head. This way you could tell at a glance of the head was too hot.

Another thing you can do that we did routinely on our diving compressors was to remove the discharge valves from the head every year to clean them in solvent.

In a shop you don't have to go to such extremes as it is not breathing air. It is not a bad idea to touch the head quickly from time to time. If you have a stuck valve the head can go from 150 degrees to over 400. Very hot head and lot of water discharge means trouble. The oil will break down very fast also. So keep a weather eye on the head's heat.

You would be surprised how many compressors have stuck or restricted (build up) on the discharge valves and people just are not aware. The pressure will be the same but the volume CFM Free Air will be about half thus doubling the time of the pilot valve cycling. The cleaning of the valves is a good idea on reciprocating units with oil crankcases. If you are changing your oil a lot it should not be something that has to be done that often but you can spend two dollars, buy a few gaskets and do an inspection. If the valves are real black, take them out and use solvent to soak and clean them. You can tell at a glance if you have a problem.

Changing oil every six months on a compressor that runs every day and always use the OEM's oil recommendation for weight. It imperative to use a non detergent oil on compressors. Most compressor use straight 30 weight ND.

Those compressors are working all the time in our shops so it is a good idea to give them the attention they require by doing the easy maintenance.

As Barney Fife would say, " Nip it in the bud". LOL


Rick

 

[Albatross Cues]

For me the air drying was pretty easy and cheap. I picked up a Bendix AD-9 off of a wrecked semi. It has a purge valve right in the bottom of the air dryer, purges every time the compressor cycles. I figured if it worked for equipment, it would have to work for drying the air for painting. I still run the inline disposable filters on the gun just as a safety.

I have checked into the air dryers from Snap-on and down at the local auto body shops. If you make friends with the local painter/auto paint suppliers, they can be a world of knowledge as they do this everyday.

The AD-9 works great for me, only changed the desiccant cartridge a couple times in God knows how many years. The purge valve kits are cheap and easy to replace, and the cartridges are readily available. They also have heaters in the bottom of them for you folks that live in cold environments, and might have the possibility of dealing with ice. Never needed that particular option, but if your compressor is outside it would keep the dryer from freezing up and not purging.

This is just one of many options available, but works well for me.

Aloha

 

[pescadoman]

For me the air drying was pretty easy and cheap. I picked up a Bendix AD-9 off of a wrecked semi. It has a purge valve right in the bottom of the air dryer, purges every time the compressor cycles. I figured if it worked for equipment, it would have to work for drying the air for painting. I still run the inline disposable filters on the gun just as a safety.

I have checked into the air dryers from Snap-on and down at the local auto body shops. If you make friends with the local painter/auto paint suppliers, they can be a world of knowledge as they do this everyday.

The AD-9 works great for me, only changed the desiccant cartridge a couple times in God knows how many years. The purge valve kits are cheap and easy to replace, and the cartridges are readily available. They also have heaters in the bottom of them for you folks that live in cold environments, and might have the possibility of dealing with ice. Never needed that particular option, but if your compressor is outside it would keep the dryer from freezing up and not purging.

This is just one of many options available, but works well for me.

Aloha

That's awesome! Never dawned on me that big trucks used air dryers or to think about the pneumatic braking system. What a great idea! You're just running a simple 12v power supply to it?

 

[Albatross Cues]

That's awesome! Never dawned on me that big trucks used air dryers or to think about the pneumatic braking system. What a great idea! You're just running a simple 12v power supply to it?

No need for 12volts unless you are using the heater, the rest in just straight pneumatic.

 

[pescadoman]

Epiphany..........