Air Compressor Buying Basics?

[Paschale]

Hi everyone,

I was in a thread about removing rust from a WM, and got some advice to use an air grinder from VA-Sawyer and Electic_AL.  It's definitely on my list of things I need/want to buy, and as I've been mulling this over, I'm wondering if I should buy one sooner rather than later.  I've had very little experience with compressors, though, so I'm not sure what the minimum requirements would be to do the things that I'd most likely want to use it for.  Any help would be greatly appreciated!

Here's what I'm thinking:

1.Using it from time to time to run tools, such as an air grinder.

2.Using it perhaps to do some blasting--VA-Sawyer mentioned glass bead blasting (which is new to me too), and in past posts, people have urged me to steer clear of sandblasting, since it could gum up the works of the bandsaw itself.

3.  Perhaps using it to repaint the WM.  I had thought about repainting once it's all rust free.  Maybe having Maaco or somebody do a cheapie $99 paint job.  Then, the thought crossed my mind with a compressor, if I buy the right one and a hand sprayer, I could do it myself.  

4.  Finish spraying for woodworking.

5.  Powering some air brad guns for woodworking.

6.  Uses yet to be determined!

I've been doing some looking in stores, and online, and I really can't make heads or tails yet of all the variables and differences one needs to consider.   : Any suggestions?  

Thanks!

Dano

[Buzz-sawyer]

Hey bud
I think a compressor is a must but there are several issues to consider..........first of all an inexpensive electric angle grinder works real well....I bought many, but the off brand china angle grinder has held up for a decade and cost 29.00 bucks.....they can cut really well with a disk and grind and polish , they are light and work great......
As far as compressors you need a high cfm capacity ( which mean cuic feet per minute....the amount or vollum of air you can push)... to run those little cheap grinders, which means a bigger motor 5 horse is min. but will work..........and big air res. bout 20 gal or bigger.
I would recomend air nailer and brad nailer , and impact  wrench ...I cant live w/o em...... :D :D
I would recomend paintin it yourself its fun and totally easy.....you can get a cambell-hausfeld kit with above mentioned tools combined for cheap or free with one of thier 5 horse compressors...like 250 at lowes for everything you need
except cheese cake to eat when your worn out from all that grindin ;)

[Norm]

Just to show you how much I appreciate having an air compressor I own three of em. Handiest tool on the farm, at the mill and in my shop. :D

Sears used to have some good deals on em too, I have a campbell hausfeld that broke after about one year of light use, not sure if this indicates anything but the old sears just keeps on plugging away. It's a five gallon size and 5 hp motor, I've banged it around for years. Plenty of other good brands out there too, after you get one you'll never know how you made do before.

[Gilman]

Paschale,

In your list of uses above, sand blasting will consume the most air, 2nd would be the grinder.  You'll need at least 22 CFM @ 90 psi for the sandblasting.  You won't be able to blast continuously but sandblasting is a miserable job and you won't mind a break. I have a 7.5 hp two stage air compressor with an 80 gallon tank and it can't keep up with a sand blaster.

Get a 2 stage pump, they are more efficient and you get more CFM/ hp that way.  60 Gal tank would be ideal.

If you don't get the bigger 5+ hp & 60 Gal tank, I'd recommend getting a smaller 2-3 hp portable air compressor and later move up to the larger air compressor.  You'll always have a use for the portable air compressor. And you can run the two compressors into one line when sandblasting.

Oddly enough, the paint sprayer is one tool that needs a large tank supporting it.  Not due to air consumption, but due to water condensating in your lines.  If you use a small tank the compressed air will not cool in time and will hold a lot of water in the air.  When the air expands in the line, this extra water will condensate and will come out your paint gun, ruining your paint job.  Doesn't matter that much on farm equipment, but on that woodworking project or a care, it is really frustrating.

Also, if you are going to use a paint gun, don't ever put lubricants in your hoses.  Oil at the tool only.

[GF]

Sand blasting takes a large amount of air, I have a two stage Industrial Air compressor made by Coleman  it keeps up with sandblasting pretty good.

I would also look to make sure it has a cast iron compressor and not an aluminum compressor.  I would prefer to pay a little more soomething that will last longer.

Here is the website for the industrial air compressor
http://www.colemanpowermate.com/compressors/industrial.shtml

I have the model IV5038023 it came with a 5hp balder motor, picked it up new for $999.  So far I have been pleased with it.

[jgoodhart]

A air compressor is a must in my book, got a 5hp 2 stage with 20 gallon tank that does most of the work painting, impact wrench, grinding and blowing the mess out the door. The 20 gallon tank allows it to be portable so I don't need to run long lenth of hose and have pressure and cfm drops. You just need electrical oulets here and there to handle the load 220 vac . I have used the 5hp for sand blasting and they will get the job done but I must wait for it to catch up. I also drug home 1 day a old 15hp 2 stage Ingersolrand compressor with about a 80 gallon tank and the compressor has a unloader for contiues running. I just run the compressor off the belt pully on my John Deere 70 diesel and I can sand blast all day at 150 psi. The important part of finding one of those old cheap compressor like that is it must have the unloading feture, that allows the compressor to stay running but it won't pump air till the pressure drops in the tank.

[Larry]

I have a 2 stage 7.5 HP compressor with 80 gallon tank.  The intention was to use it for a little sand blasting along with spray painting.  Got tired of sand blasting real quick.  Respirators, sand to buy, (and clean up) hot, and you can wear out a $1,000 compressor real quick.  We found a guy that will almost sand blast for the price I can buy sand.  It runs the rest of the tools like grinders very well.  It is amazing how much air a little die grinder can use.  My big complaint is the noise.  The 2 stage compressors in the $1,000 range run fast and generate a lot of noise.  They belong in there own little building way way out on the back 40.  I would like to sell it and get something with about a 20 gallon tank that is quiet.

Got a commercial Thomas 1-1/2 hp with maybe a 3 gallon tank for nail guns.  It has been abused and way over loaded for years but still keeps on ticking.  Only complaint is it is heavy and I think it pulls pretty close to 20 amps so it will trip a breaker now and then.

Next compressor is a cheap DeVilbiss import pancake oil less compressor.  I bought it about 5 years ago and figured with it would be dead by now.  I take it slow and easy on it and it runs good.  

I bet CK has a good advice on what makes a good compressor.

[karl]

Have worn out a half dozen or so 2 hp twin tank portables over the years- have a 3 hp 4 gallon porter cable that has the quick couplers and guages protected with a "roll cage" really like it as those were the areas most easily damaged on jobsites and in the truck- 'bout $260. Puts out 5.3 cfm@90 psi- pretty light for impact/die grinders but more than adequate for nail guns and staplers.
In the shop I have a 5 hp - 18.5cfm@100 psi with 140psi max.
Still not really big enough for serious sandblasting.
It is LOUD, It has caused a number of unsuspecting souls to call out to their Savior when it started ;) :D.
I'm satisfied with both compressors for what I use them for, course it would be nice to have a gas  one for the mill yard and those cabins off the grid.

[DanG]

I'm no expert, but I did some serious shopping when I bought mine. Ended up with a Husky from Home Depot. It is 5hp with a 26 gal tank, belt driven, cast iron cylinder, made in USA.  I think I paid a bit over $300 for it. It keeps up with all my air tools just fine, and isn't near as noisy as those "oiless" direct drive things.

Air tools to buy:
Impact wrench.. how could you exist without one?
Air ratchets...how could you exist without them?
Die grinder(whizz wheel)...how could you exist without one?
Air stapler...How could you exist without one?
Air chisel(great for digging nails out of logs)...how could you exist without one?
There's a lot more tools out there, and each time you buy one you'll be asking yourself that same question.

[Fla._Deadheader]

  I don't got none of them air thingys.  ;D ;D  All I got is a DA sander and a sand blaster (quart size). OH, and a tire chuck filler thingy. ;D ;D :D

[DanG]

How do you exist? ??? :D :D :D

[Fla._Deadheader]

  I'm just a figment of my wife's imagination : :

[Minnesota_boy]

Before you decide what air compressor to buy, find somebody with an oilless compressor in their shop.  Have them start it/use ait until it starts.  Bet you don't get one for your shop!  ;D

[J_T]

When painting I have put a large air tank in the line for more voloum and a good dryer is a must . Both are cheep .When I had a tire shop  I used Milton couplers they were the only ones that would take a lot of use and not leak.

[etat]

For a shop go ahead and spend the extra for a two stage.  In the future you'll be glad you did.  I used a 5 horse forty gallon tank for years, and grew to hate waiting for it to pump up.  Tools that take a lot of air include paint sprayers, grinders, chippers and air hammers.  Impact wrenches need a lot of volumn.  I've now got an 80 gallon two stage off brand, have had for five years, and still no complaints.  As JT said milton connectors are the best.

I too have a bone yard of them little double tank oiless compressors.  Used to wear one out about every 8 months to a year.  About a year and a half ago I bought a Dewalt, single tank portable 110 volt.  While still a oiless compressor it now contains a oil resivor that keeps a small amount of oil splashed ont he lower part of the cylinder.  As I said I've been using it a year and a half and still going strong.  They are lightweight and will pull up to three air nailers easily, though not effective for other types of air tools.

[CHARLIE]

Don't buy an oil less air cooled air compressor. They are extremely noisey.

Look for the highest CFM you can get for the money you want to pay. Be sure it is belt driven, oil lubricated with cast iron cylinders.  The oil lubricated with cast iron cylinders are a lot quieter.

I purchased a Campbell Hausfeld with a 20 gallon tank and 5HP motor. Mine is on wheels 'cause Tom told me to buy one on wheels.  I can take my air compressor to the work if I have to. If you buy a stationary compressor, you have to bring the work to the compressor.  I have had my compressor for about 8 years and have never regretted my choice.

Once you buy a compressor, be sure to keep the water drained from the tank so it won't rust. That's important!

[VA-Sawyer]

Dang,
Man, you sound about like me. All them years of working on planes got me in the habit of running an air line over to the job before moving the toolbox.  I have a regulator/separator/lubricator mounted on the side of my main box. It has 1 in and 3 outs. The first outlet is teed into the inlet so you can drop another hose off of it. The second outlet is between the separator and the lubricator, just in front of the check valve going into the lubricator. This give me clean regulated air for things that don't use oil. The third outlet is from the lubricator for feeding tools that need oil. I use different style couplings on my oiled hoses than I do my oil-less ones. Like somebody said earlier, you don't want any oil in air hoses you use for painting. This setup makes sure that the tools that need oil will be hooked up to a lubricated source. I have a 25 year old air drill that still has pretty good power after years of drilling out rivets.
Do you get the feeling that I depend on a lot of air tools too ?
VA-Sawyer

[Paschale]

Guys:

Thanks for all the replies!  I'm going to have to sit on this for a few days and process it all, and then I know I'll have a few more questions.  I did a lot of looking today at Menards, Home Depot and Sam's Club at various size compressors, so I'm gettin' a bit of an education on these things...

Need to absorb the info you guys gave me, and figure out how I ever existed without a compressor!   ;)  

Thanks!

[OneWithWood]

One thing I have done that has not been mentioned is to run a solid line around my shop with outlets where I work on different projects.  I used PVC pipe rated a 400psi.  Standard water supply line works fine and is cheap and easy to work with.  At each drop I extended the line below the coupling and incorporated a ball valve so it is easy to evacuate the line and blow out any condensation.  I mounted the compressor on wheels and use a flexible air hose to connect to the solid line.  This way I can disconnect and move the compressor if I need to.  I ran a line to the outside of the building for working on things like the crawler that I do not want to bring inside.

[Gilman]

VA,
Good idea about using different couplers for you clean hoses and oiled hoses.  I'll have to take some photos of some features I like and don't like about my air system here.

Gilman

[Rocky_J]

Paschale-
Take it to heart when you hear one after another advise against an oilless compressor. Virtually every compressor at HD is oilless except for one or maybe two models. I am also looking at that $300 deal at HD for the 26 gallon tank and 5hp belt driven compressor. The only reasaon I haven't bought it yet is because I don't have the concrete floor poured in my shop yet.

[ElectricAl]

We were given a 6 month old 5.5HP 30 Gal compressor by my Grandfather. It is oilless and really makes a racket.

It get's 4-5 minutes of run time 6 days a week.

About a year after we got it the compression ring broke.

I took the cylinder head off and looked inside..........SAWDUST

Wonder were the sawdust came from ???


Well, I ordered up the parts including a new cylinder : and reed valves and slapped it together.

To prevent that pesky sawdust from getting in the cylinder I added a K&N cleanable air cleaner.

We use to use K&N air filters on our race cars and motorcycles, so I guess its good enough for an AirCompressor

[Mark M]

Dan,

Keep in mind that the 5 hp and bigger compressors usually require 220 volts. I have a small Porter Cable oil-less that works well for my air nailers etc. It is noisy and I wish I had bought the one will oil. I also have a 5 hp Sears that works very well. Check out the farm stores as another source.

Don't forget safety glasses and a face shield (I use both) when using air tools, especially grinding.

Mark

[CHARLIE]

Mark M, my Campbell Hausfeld 5HP, belt driven, oil lubricated, cast iron cylinders on a 20 gallon tank with wheels (whew! :D ) runs on 110V.  If I had to make the choice again, I'd buy the same thing.  

My cousin bought an Ingersol Rand, which is the cadillac of air compressors, but very spendy.

[Quartlow]

ok for my 2 cents worth, 2 stage compressors do not always equate into more volume, more pressure is the goal with a 2 stage.

A friend of mine in washington purchased a single stage 5 HP quincey last year that is a low rpm 4 cylander unit. It's quiet and makes a gob of air volume wise. it only makes 135 psi but thats plenty. I checked the quincey website and can't seem to find it. I calledhim and he couldnt remember the model number off the top of his head. It's in storage right now but as son as he gets a chance he is going to get it for me.

He has ran as many as 3 lines of of it at once working on trucks and has yet to run it out of air. the best part was he bought it for less than $1000.