Yesterday, my elderly uncle gave me his Craftsman air compressor. It is basically an unused 5 year old 60 gal, 220v oiless model. I got it home, plugeed it in and WOW! This is the loudest noise that has ever come out of my garage. I closed the garage door and went outside and you can hear this thing around the corner. I cannot believe someone would design such thing. I really can't see myself using it the way it is. My question is, since it has a good tank and a basically new motor can I remove the existing compressor, turn the motor sideways, add a pulley and a 2 cylinder pump (maybe a 2 stage) and end up with a decent, quieter compressor?

I've got a craftsman air compressor and it's loud as hell too!
Don't know much about em, think they're all that way.

Some compressor designs are simply loud, and you aren't going to be able to change that without spending more money than replacing it with a quieter model.
Oilless models seem to be the noisiest, but I've seen at least one two-stage model with a crankcase that was just as bad.
Your other option is to enclose a compressor room in a corner of your shop so you don't have to listen to it anymore. Insulate the walls between the compressor and yourself, and add an exhaust fan to the room to get the heat from the compressor outside in summer, and add heat if necessary for winter.

I ran my air intake outside, made a little difference.

TechNova,
What kind of compressor do you have? Mine is oiless which means there is no crankcase - the crank, connecting rods and pistons are exposed and I thought it was these moving parts making the racket. If it is the air intake I will try to fab some kind of silencer.

My solution to the noise problem was to build a box on wheels for my noisy aircompressor, added a vent fan to pull out the heat and a baffled inlet to draw in the cooler air, sound proofed the inside of it, then ran a feed line to a filter/regulator mounted on the outside. The compressor and fan are both controlled by one switch. Plug it in, hit the switch, and use all the air you need without all the darn racket those things make. With 4 swivel wheels I can move it around in the garage, out to the drive, onto the patio, etc and use it. Double doors open to access the compressor, store hoses, air tools etc inside, and to drain the moisture trap. Downside, that flat surface on the top has collect stuff-itis, like every other flat surface at my place. Just a suggestion to save the hearing. Not a big huge project, some MDF sheets, some screws, wiring, bathroom fan, etc...

From what I have seen, two different designs have two different, comfort levels. The oil less have a crank that is driven right directly off of the motor. On these the displacement is less due to the higher working RPM. I tend to steer toward the belt driven, seperate motor and compressor unit. I have one of hte 6.5HP, 60 gallon, 240V units from Home Depot and have no problem working next to it while it runs.

Cam

I would suggest getting a new compressor and use that one as an add on tank. Not sure it's worth it to spend the money on parts when you can get almost a new one for the same price as the parts cost.

I had a Craftsman 60gal direct drive too, was very noisy and pumped very fast. It broke 2 pistons before a gave up and got a belt drive that I'm happy with. Much quieter.

Noise is an interesting thing... we perceive one noise but it is really many noises all munged together.

The "oil-less" compressors tend to be driven at higher speeds and thus generate a higher frequency of noise. It is a combination of the sound power and frequency that makes them so darn irritating.

The old fashioned belt drive compressors operate at a much lower frequency so their noise is less objectionable. Here though the major source of noise becomes the air intake. This can be silenced through muffler technology just like you use on the exhaust of your car. Longer tubes, chambers, resonant chambers, etc. can all be used to control the intake air noise.

I once bought an upright Coleman oil-less compressor because I really liked the upright packaging and footprint. I had to take it back because it was just too darn noisy to work around.

I now have a belt driven Craftsman and am much much happier with it.

You may also note that Craftsman had two different versions of the oil-less compressors. The black tank "Professional" version runs at a lower speed and is likely quieter than the much more prevalent red tank version.

Anytime you're compressor is running, theres something on the end of the air line thats making noise, sometimes really loud and sometimes not.
My idea for whats it worth, is to keep the compressor out where it can get good air circulation and all the air lines will be at the same temperature as the air in the shop, especially when painting. I'm not sure drawing cool air from outside is a good idea, you usually have to have it pretty warm when you paint, what will that cooler or warmer air do to the atomization at the spray gun. I'm guessing here so don't jump on me.
They sell ear plugs that are on a half round plastic ring that can hang around your neck, then if you need hearing protection it's real handy, you will never be sorry for using hearing protection.
Maybe some of the body shop experts can elighten us on different air temperatures, I may be way off base here, but I'd like to know.

Rob

I have a compressor with oil in it.
I draw in outside air even in winter. The air gets warmed up during the compression process (feel the side of your tank after it's run alot).
The only problem with outside cool air is the additional condensation caused when you warm up the air. I have a air drier system to solve that. It requires me to change the dessicant more often than if I was sucking warm air but it is minor compared to hearing the extra noise.
I am planning a shop addition so the compressor will be in the semi-unheated addition next winter.

Addition sounds like the way to go, I wish I had another room to put mine in.

Rob

I put my comp in the attic room above my garage and piped it down to the garage. I wired a 220 switch so I can turn it on/off from the garage. I also set it on a thick rubber mat to cut down on vibration. I can still here it but it's much better.

I had one of those Craftman 60 Gallon Upright oiless compressors and it was a pile. IF you use it for any length of time the rod will break on the compressor piston and you will have to replace it for about $60. I did it twice before I realized I could soon buy another compressor. Finally I bought a good Ingersol Rand compressor and it runs great for hours and hours. My advice would be to dump that craftsman and get a real compressor before you have to start replacing parts. The ingersol compressor is noisy too, but it is a nicer noise (kind of like a big block compared to a 4 banger??). Don't paint with that compressor because you risk it breaking in the middle of your paint job.

I am thinking about buying the 80 gal. belt drive at Sears. I going to put my compressor outside behind my shop to get rid of the noise and to free up a little more room inside.

I didn't mention before but the noisy model I have is the professional one with black tank. What's the value of this basically new unit?

I was a former engineer at Campbell Hausfeld for quite a few years working on air compressors, there are a couple of things that I can say about the noise. Your noise problem comes from 2 areas, first is the cheap reed valves in the intake, a good air filter with a silencer from a company like soldberg will help with that, you can also redirect the intake to somewhere else via a hose perferrably a high temp rubber to naturally baffel the sound waves. The second area of noise is the check valve going into the tank, unfortunately it will reach 300 -500 F depending on the type of compressor with oilless being the hotter version so there is not much you can do about that. I recommend to anyone who whats an air compressor for thier garage to avoid the oilless unless they only plan to use it a couple of times a year. Belt drive oil lubericated is the best way to go, depending on the voltage 110v usually run the pump at 700 rpm for a twin cylinder(can still carry on a conversation with it on), at 220v they run at 1400 RPM if I remember correctly (which is not too hatefull). Your direct drive oilless at 110v or 220v all run at 3450 RPM which is screaming. Not to mention you can expect about 2 to 4 times the life with a oil lubed.

As for the guy that started this thread I would very strongly recommed that you don't change the pump orientation, most tanks are designed speciffically to accomodate the stresses and vibrations associated with the pump and a cracked tank can ruin more than just your day (trust me I have seen pictures). I'm running a 26 gallon 220v belt drive and it will power just about every air tool out there, and the disadvantage is that I don't have a big reserve tank, but the refill time is less because there is a lot less tank to pressureize. In case you were wondering most of the time the difference between the red and the professional is the paint, decals and the air filter, they are the same pump and motor inside.