I'm looking to purchase a small air compressor for the shop. I want it primarily to use with a paint gun to prime and coat mdo sheets. I have no intent to build or use a sandblasting booth.
How much air do I need ?
Would a 6hp, 6cfm @ 90psi, with a 20 gal tank suffice??
What kinds of paint can I use with an air gun. Would I be able to use it to spray Jay Cooke primer for example..
Any thoughts or advice welcome
Posted by VICTORGEORGIOU (Member # 474) on :
Mike, someone else will have to advise you on volume. I want to talk about noise.
The older compressors had cylinders like a car engine and were relatively quiet. I don't know how the newer ones work but they are outrageously noisey. You can't carry on a conversation over the noise that they make.
It would be worth paying a little more to get a quieter compressor. Vic G
Posted by Michael Boone (Member # 308) on :
Mike. the Compressor you describe is plenty powerful enough foryour needs. I would consider a larger tank. If the tank is larger..you have a bigger reserve of air...so the pump doesnt run as constantly. As you work and stop..the bigger tank will be replenished. Its like a cushion. This keeps the pump cooler. Moisture is another cosideration. I have an aftercooler on my compressor.,which is simply a radiator in the air line rom the pump to the tank. cooler air holds less moisture. The water drops to the bottom of the tank...and I have an automatic drain. Each time the pump cycles...it drains the tank by means of a pressure switch
Posted by J.T. Gazaway (Member # 2001) on :
All great advice above. I second the part on tank size. A 2 hp is better on a huge tank than 6hp on a small one. As for the noise factor, the belt driven ones are much more quiet than the direct drives.
Posted by J.T. Gazaway (Member # 2001) on :
Oh yeah, If you're limited on floor space (like me), you might want to consider a vertical tank. They take up a lot less space. You can put an 80 gallon tank in a 2x2 space.
Posted by Wayne Webb (Member # 1124) on :
Michael, I just bought one of those automatic drains from Harbour Freight Tools. The drain works fine......but only when the compressor kicks on. After about 3 seconds the little plastic hose ruptures with a perfect little round hole about 1 cm wide. The hose came with the drain and is supposed to be rated at 250 psi. I mounted the hose fitting between the check valve and the unloader valve. All the fittings that came with this gizmo are for the plastic hose. Is yours copper and where did you connect it?
Oh yea mike, like michael says, a compressor with an aftercooler will make a world of difference by keeping moisture out of your lines.
Posted by pierre (Member # 1462) on :
We've had a compressor and DeVilbiss and Binks guns for years. If you want THE most powerful, smallest and quietest system available, do what we just did. Buy a 9100 Series HVLP Turbine setup. It cost $985.00, but it's the most incredible setup I've ever seen. Almost NO overspray, quiet and you can even lay down 1 finish coat of the heaviest Latex paints. The oil based go on automotive smooth. Best move I've made in years.
Posted by Michael Boone (Member # 308) on :
wayne. Minesa factory option..it hooks into ther unloader..they had all the stuff there for me.yes copper....it spits about 2-3 oz a watwer each time.which is sufficient to keep the tank empty...on this unit you can asdjust the duration of drain..
Hay Pieere... I suspected someone would recommend that setup...and Ive heard its the absolute best as well..but I couldnt say..I never used it.. These days......ANY sprayin whatsoever..goes to the bodyshop..no question.. As I get a lil older...Im reconsiderin...Maybe I DO wanna die healthy after all...
Water traps in line..also good idea.. ANd I liked the plastic plumbin I did..They have a plastic pipe suitable for air lines...its easy and way cheap
Guess what else....
WEAR A RESPIRATOR!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!.
Posted by roger bailey (Member # 556) on :
For years I bought the "high quality" american made, 7 hp or 10 hp for the body shop.
Well, we need air for some machines at Rapid Tac, this time(cause of low need) I bought a "dirt cheap" 6 hp-60 gal. tank from Wal Mart, it was one of those oilless imports($400.00 or so), the damn thing lasted about 4or5 years without problems.
I bought another one(same cost) and went another 4or5 years, no problem, and its quiet compared to a 10 hp, belt drive 2 stage etc. and now our needs are greater, the last one was runnin about 5 hours a day.
I did break down and buy another american made 7 hp two stage(a real good deal on a practically new one). But if you just need a compressor once in a while, buy a oilless from Wallys. Thats my tip today ! Roger Posted by Robb Lowe (Member # 2121) on :
Just out of curiousity, and playing devils advocate here...
1 - why do you want to spray MDO sheets versus rolling them?
2 - have you ever sprayed paint with a gun before?
Spraying with anything other than a HVLP (high volume, low pressure) turbine rig will always have some overspray, which overtime, will leave most everything within the shop speckled in various colors. Then you've got gun cleanup, air hoses to wind up and stow away, etc. Lots of extra steps and work versus a disposable foam roller or even cleaning out a good brush.
As for compressors themselves, everyone has set up straight so far. Decide whether you want to buy one good one, or several cheapies though. Also, trust me, buy a compressor at least one step better than you need right now. Sooner or later you'll get a DA (dual action sander) and that will change your life for prepping boards, and they use air like nothing else. If you're a fix-it kinda guy, you'll end up with a air-rachet, and they can suck up some air if you are tearing apart and engine or something similar.
The super 'noisy' compressors are the oil-less variety. They are more low profile than the traditional style. I have no expierence with them, so cant say if they are good or bad.
The traditional compressors look like Briggs&Stratton type engines. Less noise, a bit heavier construction and uses more space in the shop.
If buying a used one, be sure and let it run at least once from no pressure to full pressure (when it cuts itself off). They have flapper valves in the head that wears out, not a big deal to fix, but a good indicator of age and wear.
Hope that helps.
Posted by Ricky Simpson (Member # 1318) on :
Mike,
Victor brings up a good point concerning noise. I would buy one with the cast iron pump versus aluminum. There is a big difference as far as noise is concerned.
Posted by pierre (Member # 1462) on :
A respirator is a must, even with the Turbine setup, and we have a positive air flow through the paint room. This turbine pushes hot air, so the paint actually comes out warm, and because it's warm in application, it flows out smooth almost immediately. We'll never go back to a standard compressor again.
Posted by Ricky Simpson (Member # 1318) on :
Also Mike.....I dont know if you have tried it before but if your main use of the compressor will be to spray mdo, you can get a surprisingly smooth finish on mdo with a foam roller and the proper technique. Might save you some bucks.
If you do go the compressor route, I would definitely recommend a HVLP spray gun. The regular type guns have so much overspray that every thing in your shop will be covered with "the fog of overspray" and I mean literally a fog.
Posted by Steve Purcell (Member # 1140) on :
The Ingersoll/Rand T-30 is a nice shop compressor.
My Sharpe HVLP gravity feed has been treating me well for about five years. All paint types and no overspray.
Posted by John Arnott (Member # 215) on :
Mike Don't spray M.D.O. panels! I use to spray everything just to get a nice shiny surface to letter on, but that did not have enough mill thickness to the paint, so the backgrounds started failing. I learned the hard way, but I now roll the boards. Even if you need special effects, roll first, then spray the effects. Not only is it better for for the sign, but it keeps the E.P.A. off your butt and the fire deptment leaves you alone. John Arnott
Posted by old paint (Member # 549) on :
jon i kinda disagree here. i got a an old stwert warner commercial paint gun, 5 hp sears alum oil sump 20 gal 220v compressor. now the sears i bought new in 86-87 and have done everything from sprayin mdo panels to sandblasting a boat trailer with it. as for sprayng mdo, i 1st coat them out with KILZ, then i spray then with A/ENAMEL car paint...yep just like whats on the automobile you drive. used to work at a NAPA store and learned about missmatch paints(they usually just chuck em) but you can buy a gal of a missmatched white,blue green, red, non metalic paint for $10-12 bucks a gal, normal price is $50-60. as for longevity ...the car paint will last longer then anything you can roll. added feature is if you paint on these panels ..you make a mistake or drip paint on it, you can wipe off with mineral sprits and never disturb the background paint.
[ March 11, 2002, 02:38 AM: Message edited by: old paint ]
Posted by TransLab (Member # 470) on :
Thanks people ... for all the info.
You've given me much food for thought, and many points to ponder ..
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