Quiet air compressor?

No. All compressors are certainly not equally noisy. I had a 1.5hp Sanborn unit, one of those cheeseball things on 2 wheels. Then I got a 2-stage Quincy unit, solid, all cast iron, pretty old, and put a 5hp single phase motor and new controls on it. It is quite a bit less noisy than the little one.

Quiet usually equals heavy, which usually implies expensive. A side benefit of putting your compressor outside is that it's cheaper to compress cold air than warm air.

Avoid anything made by Campbell-Hausfeld, Husky, Sears or the like, as well as anything sold at a lumberyard or big box hardware store. Those are all el cheapo units cranked out by the bazillions for joe homeowner. Buy a solid unit made by Quincy or Ingersoll Rand, hopefully an old solid one. If the compressor comes with a motor bigger than you can run you can always put on a smaller motor and run the pump slower by changing sheaves and belts, and it will be even quieter.

There's a nice I-R 7.5hp unit which is sold by Harbor Freight. That's a nice compressor but you'll have to run a 60A 220V circuit for it.

GWE

I have an IR 11.8 runs extremely quiet, I have it in my basement although I can hear it when I am in the shop it does not bother my wife upstairs nor does it wake my 3 y/o when he is napping of the first floor.

Searcher1

Rotary screw compressors. Very quiet. Beaucoups air.

Not cheap.

--Winston

Generally speaking, compressors with lower rpm motors are quieter. Depending on your budget, have a look at these:

Also have a look at item 16561 on sears.com. It is a consumer grade two stage compressor that is supposedly quiet even though it is oilless. It is built cheap, but it is cheap too.

It depends a LOT on design. You won't find this at Sears, but a rotary vane compressor is a lot quieter than most piston compressors. (I'm not talking about Gast carbon vane compressors, here. There was a guy selling these on eBay a couple years ago.)

You can always build a muffler to silence the intake. A compressor with an automatic unloader won't make that loud hiss every time it shuts off. Mostly, pump speed is related to noise, so a larger, slower turning compressor will usually be quieter that a smaller one turning faster.

I have a 2 Hp Quincy 2-cyl compressor that is very quiet, and I have made no attempt to silence it. I can work right next to it without it being much of an annoyance. It is right behind my milling machine, in the basement, IN the house! You can tell it is running upstairs, but it is not annoying at all up there.

Hmm, my Quincy single-stage compressor is run by a 2 Hp motor, and produces 6.3 CFM at 90 PSI. I can run a die grinder full blast with it. Thge tank pressure DOES slowly drop to about 70 PSI if I run the grinder continuously for 10 minutes or so.

It sounds like a 3 or 5 Hp single-stage compressor might do for you. You can look for a Quincy or other high-end brand used, and it likely will give more life than a brand-new consumer-grade compressor. (And don't be fooled by the Sears "professional" label, it is all low-end consumer-grade stuff.)

Jon

Grant Erwin wrote: If the

That is not absolutely true. I have a Quincy 2 Hp 2-Cyl single-stage compressor that originally had a 1 Hp motor and was turning about 450 RPM. Since I wanted to get all the air I could, I replaced the motor with a 2 Hp motor and got the right pulley to load the motor to rating. (This was bringing the compressor up to the manufacturer's full rating. Depending on what year spec sheet you looked at, the rated speed was either 900 or 1000 RPM.) Anyway, I was pleasantly surprised that doubling the pump RPM made it MUCH quieter. At 450 RPM, the inlet valves (disc type) were bouncing, making a buzzing or humming sound. At 915 RPM, they open fully for the entire intake stroke, and the compressor is really quiet for its size. I could muffle it, but there's really no need.

Jon

No kidding! Although they are made in small sizes, almost nobody EVER buys one under 25 Hp, due to the cost difference. They are also a bit more finicky about maintenance!

Jon

On Thu, 18 Nov 2004 00:30:37 GMT, Richard Ferguson vaguely proposed a theory ......and in reply I say!:

remove ns from my header address to reply via email

A heck of a lot of the noise is at the intake, when the valves open and shut.

Not recommended to be done for too long, but to test the actual compressor noise, try to block the intake port while the comp is running, if you can find one to test in the shop. If it's quiet enough then, you can add a silencing system. These can be home-made, but the one I built is fairly bulky, using a baffled box.

***************************************************** Dogs are better than people.

People are better than dogs for only one purpose. And then it's only half of ofthe people. And _then_ most of them are only ordinary anyway. And then they have a headache.........

Suggestion, First borrow the loudest, noisemaking, shaking, vibrating compressor you can find and let SWMBO listen, then replace it with the compressor that will meet your present needs and with room for expansion in future. I ended up with an IR 2-stage 5 hp, and no, it will not run my 3/4" impact continuosly (sp).

John H.

That's why I added "preferably an older one" to avoid the off-shoring that has taken place recently. Good point, though. GWE

You can rig up a muffler system for any compressor. The noise is mostly on the intake suction, more so than the mechanical sounds of the motor and pump. just add a muffler to the intake side, and then duct it out side or into your attic.

fred

BEWARE - the Quincy is a "real" compressor, and powering it with a 2 hp motor will get you more air than most (if not all) of the 5,6, and 8 hp "home" compressors. My quincy compressor with a 5 hp motor puts out 21 cfm at 160 psi - a whole lot more than any of the sears/ingersol rand/whaever homeowner compressors. These cheap compressors use a small compressor and a big motor. Industrial compressors like the quincy are typically the other way