Air Compessor - no idea what I'm doing

I think the time has finally come to buy an air compressor. Unfortunately, I know nothing about them other than get the biggest one you can afford. My garage is only wired for standard 120 volts, so my options are limited, and I'm probably going to buy used.

The use will be to occasionally run air tools, maybe hook it up to a media blaster and possibly at some point in time to do small paint projects. The media blasting and paint are what have me looking at the 30 gallon tanks.

I was considering this:

http://raleigh.craigslist.org/tls/5261399608.html

Wondering how hard this will be to fix:

http://raleigh.craigslist.org/tls/5260554919.html

Best I can say is don't buy an oilless. I have had no luck or joy with them. They are loud and vibrate-ey enough to make a top fuel rotary look like a soothing white noise machine with the longevity to match.

I suggest running a 220 line out to the shop. You are not really going to be painting or running an abrasive blaster tool with anything under about 4 real HP, or 6 HP as they are called today. Even a DA sander will max that out, and 4 real HP is going to take a 220 line. That's 4KW. 40-ish amps on a 110V line. Give or take, SWAG.

Dr. Hess wrote: I suggest running a 220 line out to the shop. You are not really going to be painting or running an abrasive blaster tool with anything under about 4 real HP, or 6 HP as they are called today. Even a DA sander will max that out, and 4 real HP is going to take a 220 line. That's 4KW. 40-ish amps on a 110V line. Give or take, SWAG.

I second the 220v idea. And add that the tank needs to be at least 60 gallons. I bought one of these a couple of years ago:

http://www.homedepot.com/p/Puma-60-Gal-3-HP-Electric-Single-Stage-Air-Compressor-PK-6060V/204343981

I paid about $450 at Northern Tool for it on sale and with a coupon.

I use it for a small media blast cabinet (barrelblaster.com), sanders, grinders and painting, but only on a hobbyist level. It is sufficient for those things, though barely. I do have to wait for it to catch up sometimes when I've been at the blast cabinet awhile or if I've been running the DA constantly for a time. It would be unacceptable in a commercial shop, but works OK for me.

If you want to do anything more than that, you ought to look at two-stage compressors. The least expensive one I've seen is from HF. It actually gets pretty good reviews, but will set you back about $750-$800.

Try garagejournal.com for more information on air compressor purchasing than you can swallow in a lifetime.

So, get a 220 and try to find an oiled model.

Like this: http://raleigh.craigslist.org/tls/5181888086.html

My dad bought me a $25 broken compressor off Craigslist a couple of years ago for a Christmas present. Locked up motor. Dropped the motor off at the local commutator place for a $100 rebuild. Masked the labels and gave it a good cleaning and coat of paint. Good for another 25 years. They are simple machines, and I'd rather have old tools than new junk.

You want 220 because next on your list will be a welder.

If it doesn't have a belt driven compressor it will be loud and inefficient. I was in the same situation with no 220 (I rent) and waited until I found a 110v model that was belt drive. It's wait quieter than the oiless direct drive I had a couple years ago. My neighbor has an old craftsman that is similar style and it ran a sander and paint gun.

Some of the belt driven compressors are loud. I know mine is. It would really be cherry picking if you could find a two stage, 60 gallon compressor that runs at 1,725 rpms. You cannot get a good deal on a compressor around here. You may want to check out some estate sales.

It's all about CFM @ (X) PSI. Look at the rating given for 90 psi. A double digit figure is required for blasting, painting, sanding. I wouldn't buy one with less then 11 cfm @ 90 psi.

Brett_Murphy wrote: So, get a 220 and try to find an oiled model. Like this: http://raleigh.craigslist.org/tls/5181888086.html

Yes. That one is a good deal.

I have a rental home with anemic garage wiring, and a 26 gal Husky I bought used for $250 I think? It was under $300. The compressor is oiled and belt driven. My requirements were belt driven and oiled. I wanted it to be quiet as possible and the biggest vertical tank I could find. Someday I'd love to have a small tool shed outside the garage where it could be mounted. Even though it's relatively quiet, it still makes noise.

A new/ used 220V 5hp 60 gal. single stage, oiled, cast iron pump will do what yur lookin for. Duty cycle on these will prolly be around 50%, gotta let 'em regen... lotta stop n go w/ a DA sander, media blast or air hog tools but still a good compromise. The ones I've used had a lot of moisture so a good filter/ separator or dessicant drier is important for painting and media blast. There are sites for DIY aftercoolers/ air dryers so Google that if ya want the driest air. Moist air can clog your media blast.

Might actually be more than what ya want now but you'll be glad ya did down the road.

When you are checking the output, also check what rpm the pump runs at. I have a "5" horse single stage 5500rpm unit at home that makes a rude enough noise I have it in a different part of the building, and the 5 horse Dev-air unit at the shop is a 2 stage 1700 (or so) rpm unit that doesn't even make you raise you voice during a conversation.

If you can track down a Devilbiss or Binks unit built in the 50's or 60's you will be happy...other than the floor space you need to give up for it.

This is a new version of the small unit that's been built since WW2.

It's awful easy to spend other people's money...without knowing anything about your garage and the wiring situation, that may cost a lot of money.

Oh, and it's 240 volts.

This is what I did. I have about $700 in it. It will be left to the kids when I die. 18+ CFM at 175psi at 900 rpms. It's as quiet as a tomb.

https://grassrootsmotorsports.com/forum/build-projects-and-project-cars/1971-quincy-325-roc-13-air-comptessor/68684/page1/

This is the only compressor I have ever used that will not only keep up with every tool I own, it will fill and shut off while sand blasting, rather than having to wait for the compressor to catch up.

Go as big and as old as you can afford. Buying a old industrial compressor will get you 10 times the machine a new consumer grade will. You won't regret it.

stuart in mn wrote: Oh, and it's 240 volts.

Whatevs...it's enuff to kill ya. What else do you need to know?

When shopping for used unit look and see if it has a Cert tag welded to the tank. The newer box store compressors are not certified tanks and as such are made of thin dog E36 M3 recycled tin cans and rust from the inside out if there not drained often.

Dr. Hess wrote: I suggest running a 220 line out to the shop. You are not really going to be painting or running an abrasive blaster tool with anything under about 4 real HP, or 6 HP as they are called today. Even a DA sander will max that out, and 4 real HP is going to take a 220 line. That's 4KW. 40-ish amps on a 110V line. Give or take, SWAG.

actually.. about 34 amps.. more than twice that of the average household outlet (rated for 15amps) The same Compressor running on 240v will only draw about 16 amps

Most of an air compressors noise comes from the intake. Routing the intake through a radiator hose to a box will make it quieter. If you have an old car air box it will be even better, and the filter should last forever.

I built my own air box with the stock filter inside, and it makes 1/4 the noise it used to.

Get an auto drain valve

Toyman01 wrote: This is what I did. I have about $700 in it. It will be left to the kids when I die. 18+ CFM at 175psi at 900 rpms. It's as quiet as a tomb. https://grassrootsmotorsports.com/forum/build-projects-and-project-cars/1971-quincy-325-roc-13-air-comptessor/68684/page1/ This is the only compressor I have ever used that will not only keep up with every tool I own, it will fill and shut off while sand blasting, rather than having to wait for the compressor to catch up. Go as big and as old as you can afford. Buying a old industrial compressor will get you 10 times the machine a new consumer grade will. You won't regret it.

How old is too old and are their some brands to stay away from? I see a good amount of old compressors but I have no idea which ones are serviceable and which are just a rats nest waiting to happen. Ideally I would find a 60-80 gallon horizontal that I could mount in my attic.

For instance....

http://tampa.craigslist.org/pnl/tld/5223306676.html

This thing looks massive

Enyar wrote: For instance.... http://tampa.craigslist.org/pnl/tld/5223306676.html This thing looks massive

Thats about 6ft long 3.5ft wide

There is this, but it is HUGE.

http://raleigh.craigslist.org/tls/5239616646.html

In reply to Brett_Murphy:

That's pretty much the exact same compressor I have. Just the horizontal version. It will do everything you ever need a compressor for. I paid $400 for mine with a bad motor and other problems.

Do It!!! That's a $2500 compressor new.

I may have to rent a truck.