I've decided to bite the bullet and get myself an air compressor and air tools for working on the truck. There are lots of models out there and prices vary wildly. From experience what size should I be looking for? Will be used almost exclusively for mechanical projects. They seem to have three different ratings - size (gallons), pressure (psi), and power (horsepower).

Recommendations are appreciated.

 

If you're just using it to run a 1/2" impact, air ratchets, and that kind of stuff a 25 gallon would be fine. I have a small 25 gallon Harbor Freight one that I've used fairly heavily over the last couple of years between the boat, truck, and various other projects.

H-B stuff isn't top of the line, but for $130 or so it works for me. I think max PSI is 120# or so. You can get a two stage unit that will get you 175 PSI, but you probably won't need it.

I painted my 20' aluminum boat with mine, but it has a hard time keeping up with a regular (not HPLV) gun. If you're doing body work then you'll need a lot more air capacity, sanders, sand blasters, and things are air hogs.

I like upright units since right now I just have two car garage to work in, but that's just me.

Impacts are great time savers and make life so much easier when you're taking something like harmonic balancers off.

 

home air compressors - Google Search

 

plenty of threads in the garage and work shop forum. you can read until your head hurts!!

 

^^^^^^^hahahahahahahaha

 

I have a Craftsman that is similar to this one. I hate it!


It's loud and takes forever to fill the tank. It pretty much runs constantly with even modest use.

The most important number to look at when comparing units is the CFM. (Cubic Feet per Minute) It is usually rated at 40 PSI and 90 PSI. Look for the highest flow for the best performance. After that, I would have to hear how it sounds.

 

Stay away from oil less....

I have a friend that repairs air compressors and he says they will not hold up to much use, except maybe a nail gun or light use like that, and when they give trouble, parts are hard to find....

He says you can buy a new pump for about the same as repairing. If they are still making a pump that will fit your controls and tank...

 

I second the comment about the oil-less, I rarely use mine due to the excessive noise. If I would have know I never would have purchased my Porter-Cable unit.

 

I "third" the votes for NO "oil less" compressors. They're LOUD, they fail and...they're LOUD.

CFM, and not noise, of course, is the critical criteria, as was stated. Ignore any CFM ratings at less than 90 lbs.--most of the tools you'll want to use need the higher pressures.

Look for the lowest rpm one you can find. Typically, they are belt-driven, so you will see the big flywheel behind the shroud/screen. This means it's a separate pump and motor design. That's what you want--then you can repair/replace easier.

I have a nice, DISCONTINUED Sears, 30 gallon vertical model. It's oil filled, belt drive and turns less RPM than the ones you don't want. Spend the money, as you won't get good value if you get something that's weak, LOUD and doesn't last long.

The stats on mine are:

6.0 CFM @ 90psi.

2 h.p. continuous (5 hp max. but don't count on it--this rating was before the lawsuit on such things--I could have joined the "Class Action" but didn't bother--LOL)

1,950 RPM.

Max. pressure: 135psi.

Price: Was something like $340. I bought two of them on closeout for $185.00 and $220.00 each. Apparently this model represented too much value for the dollar, so it had to be dropped. My buddy and I got the last two in that store.

Mine's damn loud at 1,950RPM--I can't imagine what an oil-less model at 3,000RPM or whatever they run at must sound like.

I've not tried to run a DA with mine, or a paint gun, but it's almost certainly not up to it. IMO, real bodywork would require 5hp continuous.

Good luck.

 

The only spec that matters is cfm@90psi and you want as much of that as you can afford. I have a belt driven unit that delivers 5.5cfm right now and it's enough for an impact gun but the air ratchet can deplete the supply pretty quick. Air grinders and drills also use a lot of air and sand blasting is a real pig. IMO you really want at least doule that capacity to run these tools and tripple if you do any blasting.