Type of air compressor...

[dternst]

Which type of air compressor, oil-free, oillube, 2-stage oil pump, etc is the prefered type of air compressor? Which requires the least amount of maintenace?

Thanks in advance,

David

[gb387]

I just bought a new compressor about 2 weeks ago.... Only after a long search and here is my opinion.

I had a craftsman oil free single 2 stage compressor first and I did not like it so it went back... WAY to loud and the oil free/worry free pump gave me the worries, no oil come on! It was like the one below.

This has a 2 stage oil free pump.
http://content.sears.com/data/product_images/009/16778/00916778000-dlv.jpg

Here is another: This has a single stage oil free pump.
http://content.sears.com/data/product_images/009/16731/00916731000-dlv.jpg

For me its oil pumps all the way... either an aluminum pump with cast iron sleeves or better yet a solid cast Iron pump. Yes there might be a tad more maintenance with an oil pump, changing the oil and checking the oil level from time to time and tightening the belt(s) from time to time. Here is what I like about them (solid cast iron oil pumps), they are much quieter, run cooler, and some might argue this but more durable than oil free pumps, I have seen this time and time again where I work when oil free pumps fail. Now I have and really like the one below(husky pro).

Here is the one I have now: This has a solid cast iron oil lube pump - single stage.
http://www.homedepot.com/cmc_upload/HDUS/EN_US/asset/images/eplus/045564587338_4.jpg

Here is another: This has an aluminum oil lube pump with cast iron sleeves - single stage.
http://content.sears.com/data/product_images/009/19541/00919541000-dlv.jpg

Here is another: This has a solid cast iron oil lube pump - 2 stage.
http://www.homedepot.com/cmc_upload/HDUS/EN_US/asset/images/eplus/045564587321_4.jpg

Now a 2 stage pump (both oil free and oil lube) is going to provide you with a higher pressure say 175 PSI vs a single stage pump at say 135 PSI if you want or need the higher pressure 2 stage is the one. If 135 PSI is fine single stage is for you.

[gb387]

EDIT photo moved to above post.

[dodgecharger-fan]

I have the 60 gallon, stationary version of this one.
It's great.

http://www.homedepot.com/cmc_upload/HDUS/EN_US/asset/images/eplus/045564587338_4.jpg

[gb387]

dodge... I really like mine couldn't be happier! I just finished getting the separator and fittings that I wanted hooked up the way I wanted, just need to make a bracket to support the regulator, separator and fittings, I don't want to pull on the hose and pull off the pressure switch and everything else. I wanted to keep it mobile so its all mounted to the tank.

[sca037]

I agree that having to change the oil once a year is a worthwhile trade for the quieter (and possibly longer living) belt driven compressors.
I have a 20+ year old 220V 2HP Craftsman with a twin cylinder SINGLE stage compressor, which provides me plenty of volume at 150psi or less. A multi-user setup might need more airflow, but unless you need higher pressure the increased volume of a single stage twin might just be the hot ticket.
Other than annual oil changes, the only maintenance I've had to do over the years is to change the belt and replace the head gasket (once each).

Brian

[ultgar]

Here are a few tips on buying compressors.......

1. Buy the most CFM at 90psi that you can afford. Forget about hp ratings. My little 5hp rotary screw compressor makes 25cfm at 90psi. Most air tools require a working pressure of 90-100psi.....a manufacturer's claim of 12cfm at 30psi is useless. Sanders and grinders use up plenty of air volume. Average size sandblasters often need 10-15cfm alone.

2. Buy the biggest storage vessel (fancy name for air tank) that you can handle. More air storage means less compressor cycling.......if you're using a grinder or polisher with a 20 or 30 gallon tank or blowing the water out of your sprinkler system in the Fall, you compressor will run non stop. A 60 gallon vertical tank takes up very little space. 80 gallons is better. Car dealerships often go to 120 gallon or larger.

3. Look at running speeds (RPM's). Higher RPM's mean more noise. A single stage compressor running 3000rpms is going to be a lot noiser than a 2-stage or rotary running under 1000rpms.

4. Lower peak pressure means fewer leaks. Why buy a compressor with a 175psi peak when the most you'll need is 90-100psi. The only time I run into higher pressure requirements is if I'm doing a shop with tire changers. Most tire changers require 140psi operating pressure. If you've got a lot of air plumbing in your workshop, you're more likely to develop leaks running higher pressures. For the average garage, a compressor with a 125-130psi shutoff is fine.

[JasonJ75]

For me its oil pumps all the way... either an aluminum pump with cast iron sleeves or better yet a solid cast Iron pump. Yes there might be a tad more maintenance with an oil pump, changing the oil and checking the oil level from time to time and tightening the belt(s) from time to time. Here is what I like about them (solid cast iron oil pumps), they are much quieter, run cooler, and some might argue this but more durable than oil free pumps, I have seen this time and time again where I work when oil free pumps fail. Now I have and really like the one below(husky pro).

Here is the one I have now: This has a solid cast iron oil lube pump - single stage.
http://www.homedepot.com/cmc_upload/HDUS/EN_US/asset/images/eplus/045564587338_4.jpg


I just bought this bad boy Saturday and love it! I looked long and hard at the 60gallon version (only ~$60 more), but I a) don't have 240v in the garage and b) don't have any plans on doing the kind of work that would require the extra capacity until I get into a bigger house/garage.

I don't think there is really any debate that an oiler is going to last longer than an oil free until. Particularly when you start doing more than just filling the car's tires with air. I find it funny that the 'maintenance free' units are advertised like they save you so much time. We're talking 11 ounces of oil once a year. :willy_nil

Just to echo other's comments, what's the best compressor really comes down to what you want to do with it. More CFM/Bigger Tank is always better, but if you're not going to use it why buy it? This is really a 'what kind of car should I buy' question. First decide what you want to do, everything else will fall into place.

[240kid]

i have an oil-free compressor, just recently got it, and it is pretty noisy and all, but it gets the job done, and it has a 3 year warentee, although i agree that changing the oil on the compressor is a minimal ammount of maintanance

[OzCop]

Interesting thread. I bought a two stage 35 gallon, 6hp Craftsman about 3 years ago, and it recently locked up. Not sure if it's the motor or the compressor itself, but all it will do is hum. It is a 220 setup. I intend to take it to the Sears repair center and see if they can fix it, but in the meantime, I have been using a 30 gallon, single stage, 5hp, 110 that is not only more quiet, but seems to be much more efficient. It's also a Craftsman, but is about 10 years old.
I am getting a tire changer that will require a good air supply. Someone mentioned 140 PSI. Is that sufficient to run most tire changers? Thanks....

[casaleenie]

Damn, I thought an air compressor was an air compressor... Looks like I've got some homework to do...
Should I have the 220 run to the garage now?????? and keep my options open. :withstupi

[OzCop]

Good info on this stuff...
As regards my old (3yr) compressor, the Sears repair facility advises it will cost more to repair it than a new one costs. I picked up my heavy duty tire changer last Friday, and need to purchase a new one. Ultgar mentioned that 140 psi is required to run a tire changer. Sears has a 60 gallon tank, single phase, oil type 7hp compressor with max 150 psi. However, at 40 psi, it operates at 12.4 scfm, and at 90 psi, only 10.2 scfm. Would this be sufficient to operate the tire changer?
Thanks.

[Major Ramifications]

[QUOTE=OzCop]Interesting thread. I bought a two stage 35 gallon, 6hp Craftsman about 3 years ago, and it recently locked up. Not sure if it's the motor or the compressor itself, but all it will do is hum. It is a 220 setup. QUOTE]

Is it an oil lubed or oil free compressor?

[OzCop]

Yeah, it's the oil free type. Just picked it up from Sears today, no repair as they wanted 400 plus to replace the electric motor. Bought a new one from Sears, belt drive type that does require oil, 7hp, 150 psi, 60 gallon upright, 240 connection. Just hooked it up today and got it running. Since it is stationary, I need to run some conduit to get the hose connection in the location I need...

[GearHead_1]

Since it is stationary, I need to run some conduit to get the hose connection in the location I need...

Conduit? Please explain.

[Major Ramifications]

I think he meant conduit in the acedemic sense of the word. I don't think he meant electrical conduit, but I was wondering.
I have found copper pipe to be the best for air piping. It is easy to work with, inexpensive, and it is cold so it helps the moisture in the air to condense, where it gets caught by the trap. We run a main line around the room and came off of that with a riser for each drop and a drip leg with a ball valve 6" below the quick connect.

[OzCop]

Yeah, should have been more clear on that. I read another thread advising copper may be the best way to go...

[chaotik]

I have the same stationary 60 gallon dodgecharger-fan has...LOVE IT!!