A quiet compressor?

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Backally

Backally

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Right now I have a Craftsmen 6hp 33 gal compressor. 6.4cfm @ 90psi. It’s screaming loud, showed 92db on the other side of my 2 car garage, I put hearing protectors on before turning it on. Building a new house with a 1650sq ft garage and a lift. I want to run lines for the compressor, so we were standing there looking at the foundation and wife says since I’m running line why don’t I put it in the basement? Would probably be right under our bedroom. Is there a comparable compressor that would be quiet enough to do this? Or at least a quieter one for the garage?
 
The old 2 cylinder cast iron compressors ran slow and were quiet. Sounds like your compressor rins fast and screams. RPM and CFM delivered are what you have to look for. Low RPM and high CFM. Not too many are built the old school way nowdays. Big shops pull their air from outside which helps. Boxing in and insulating is not a great idea. Too much heat. Heat causes failures and moisture.
 
Upgrade to a larger capacity, 2 stage (more efficient) compressor. Remember that an internal combustion engine is just an air pump powered by a fuel. You can build a big inch low, rpm stroker or a short stroke, high rpm motor. I use an 80 gallon, 7 hp, 2 stage compressor at home. I use it to supply my sand/bead blast booth. I wore out 2 60 gallon Craftsman oil-less compressors in less than 4 years. My 80 gallon 175 psi is over 11 years old now. The 60 gallon ran continiously and the larger model now runs from time to time. The more reserve capacity that you have, the less it has to work. Rubber mount to a concrete floor and install a large, free flow muffler. Just like on your car. More economical in the long run.
 
X2 on what MoparLeo said. I got mine a year ago, a 60 gallon single stage from Northern Tool, and I'm very happy with it. It is fairly quiet for a big compressor. I do wish I'd ponied up the bucks for a two-stage, but this one meets my needs handily.
 
Look up the newer scroll compressors. They’re supposed to be pretty quiet and have great delivery
 
440seven said:
Guy might be a millionaire. He didn’t note a budget. Building a nice garage with lift may as well pony up and get your space the way you want it.
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One thing bad about rotary compressors is that they are made to run constantly. They are more for industry and don't cycle on and off like the piston compressors like what you would need for a home shop. And yes they are a thousand $ or so more than a good piston compressor. I sold compressors and shop equipment for 28 years and I know a little about them. A 5 horse 220volt 80 gallon 2 cylinder 2 stage cast iron unit is about all a home shop needs. Quincy sells them for about $1800.
 
Screw compressors are not really quiet. We have a half dozen of them at work and they are quite loud. They are made for high volume continuous duty, not really harry homeowner equipment.
I did a lot of shopping around and ended up getting a Quincy. Buy one of these and it will last your lifetime. The key to quiet is the low RPM (1750). I had mine in the garage for a year but it put out too much heat. I built a compressor building attached to the outside of my garage and its perfect. Its been out there for 2 years and its the best thing I ever did.
When im in the garage I can just barely hear the compressor running.
At 22.6 CFM this thing is no slouch. It will run any air tool and I do a ton of sandblasting with it.
Quincy QT-7.5 Splash Lubricated Reciprocating Air Compressor with MAX Package — 7.5 HP, 230 Volt, 1 Phase, 80 Gallon Vertical, Model# 271C80VCBM | Northern Tool + Equipment
Other Quincys
Quincy Compressor | Air Tools + Compressors | Northern Tool + Equipment

Get a compressor with more cfm than you think you will need. Also watch out for cfm ratings at 90 psi. Many of the cheaper compressors list their cfm @ 90 to make them look better than they are. My compressor is rated at 175 psi but I only run it at 125.
 
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MoparMike1974 said:
Screw compressors are not really quiet. We have a half dozen of them at work and they are quite loud. They are made for high volume continuous duty, not really harry homeowner equipment.
I did a lot of shopping around and ended up getting a Quincy. Buy one of these and it will last your lifetime. The key to quiet is the low RPM (1750). I had mine in the garage for a year but it put out too much heat. I built a compressor building attached to the outside of my garage and its perfect. Its been out there for 2 years and its the best thing I ever did.
When im in the garage I can just barely hear the compressor running.
Quincy QT-7.5 Splash Lubricated Reciprocating Air Compressor with MAX Package — 7.5 HP, 230 Volt, 1 Phase, 80 Gallon Vertical, Model# 271C80VCBM | Northern Tool + Equipment
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I hope they listen to you. They didn't care to hear what I had to say. I guess 28 years of experience doesn't mean squat!
 
Murray said:
Mount the compressor outside and make an enclosure.
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This^^^

Cheap metal shed next to the garage works.

You don't really want the compressor in the garage with you if you are painting. Outside, the compressor will get fresh air which is what it wants
 
I put mine outside under cover. 5 HP slow speed three cylinder single stage. Piped galvanized into the shop. Quiet and well performing-------------------------
DSC00404.JPG
 
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I have my big one outside the shop. My little one is the one I use all the time though and it's in the shop. When it cools off here, I am going to move it outside, under the shed, next to the big compressor. Will be much quieter outside.
 
Don't box them in. Don't enclose them. Look at the compressor heads. They have cooling fins for a reason. If you box them in they get very hot, can damage the compressor and the electric motor (which gets very hot as well) and heat creates moisture. You don;t want that in your air lines.
Murray said:
Mount the compressor outside and make an enclosure.
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Rainy Day Auto said:
This^^^

Cheap metal shed next to the garage works.

You don't really want the compressor in the garage with you if you are painting. Outside, the compressor will get fresh air which is what it wants
Click to expand...
 
Thanks for the replies. To answer some of the questions, no, I am not a millionaire. The car lift was a compromise...wife wanted a zero entry house for when we get old, I wanted the lift. We're both happy. So a high dollar compressor isn't in the budget. I also think I need to keep it to a 120v, I don't know the layout of everything and so may need to move it. Outside won't work, neighbors are to close and wife put the kibosh on that. Thought about enclosing it and thought it would get hot, thanks for the confirmation. The 6.4@90psi pretty much works for what I do. I have done a little spraying, and use a die grinder once in a while but not a great deal, so although not ideal it does eventually get the job done. If I could get more CFM I would, but at this point I need something quiet. 92db is somewhere between a train whistle at 500' and a subway train at 200', so it's flipping loud in an enclosed garage. I see some show 70db but they are smaller and probably would not be ideal, I agree more is good. So need to continue to search.
 
toolmanmike said:
Don't box them in. Don't enclose them. Look at the compressor heads. They have cooling fins for a reason. If you box them in they get very hot, can damage the compressor and the electric motor (which gets very hot as well) and heat creates moisture. You don;t want that in your air lines.
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That is why a metal shed works, you open the doors when you run it and close and lock when you want to store securely.
 
Backally said:
Thanks for the replies. To answer some of the questions, no, I am not a millionaire. The car lift was a compromise...wife wanted a zero entry house for when we get old, I wanted the lift. We're both happy. So a high dollar compressor isn't in the budget. I also think I need to keep it to a 120v, I don't know the layout of everything and so may need to move it. Outside won't work, neighbors are to close and wife put the kibosh on that. Thought about enclosing it and thought it would get hot, thanks for the confirmation. The 6.4@90psi pretty much works for what I do. I have done a little spraying, and use a die grinder once in a while but not a great deal, so although not ideal it does eventually get the job done. If I could get more CFM I would, but at this point I need something quiet. 92db is somewhere between a train whistle at 500' and a subway train at 200', so it's flipping loud in an enclosed garage. I see some show 70db but they are smaller and probably would not be ideal, I agree more is good. So need to continue to search.
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I always laugh at the guys who say "get a 220V" whether it's a compressor or a welder. Either of those pieces of equipment will do anything you could ever ask to a car in 115V. All I can says it, it must be nice to just be able to buy what you want. I like you it sounds have never had that luxury.
 
SGBARRACUDA said:
If you look around you can find a deal on older top of the line compressors. I found a cabinet shop that was closing down and Bought a big Comp Air/ Kellog 220 6 horse 2 stage comp. for $300.00. I mounted it outside on a slab with a roof over it. It's pretty quiet inside the shop and runs everything I need it to. This is kinda like the one I bought.
http://yabe.chudov.com/CommpAir-Kellogg-Horizontall-Air-Compressor-5-HP-80-GAL-17786/DSC_0029.JPG
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That's real similar to the big one I have out back. It has a Kellog American tank. It's a horizontal fat boy. I think it's either an 80 or 120.
 
toolmanmike said:
Don't box them in. Don't enclose them. Look at the compressor heads. They have cooling fins for a reason. If you box them in they get very hot, can damage the compressor and the electric motor (which gets very hot as well) and heat creates moisture. You don;t want that in your air lines.
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Heat does not "create" moisture, it is already there. But it can keep the humidity vaporized and send it down the outlet instead of condensing it in the tank.

But you SHOULD be able to build an enclosure that is vented, all you need "at least" is how it's done for combustion air---grills down low and grills up high, that create a "chimney effect" to flow air up and out. "At the worst" you might have to have a high mounted exhaust fan to encourage a stronger draft. Insulate the enclosure, and choose an area to reflect the noise away from the shop area "out back" so to speak.

But the BEST is the old school cast iron belt drive "slow" pump. some of those old girls--even a 10 hp 3 phase---you can stand there and hold a conversation, "at least when I was young" and could hear!!
 
RustyRatRod said:
That's real similar to the big one I have out back. It has a Kellog American tank. It's a horizontal fat boy. I think it's either an 80 or 120.
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After about 3 years use, I had to have the electric motor rebuilt which cost $125.00? and a new belt and that is it. I think if I recall it is a 1984 model. Oh and the shop that rebuilt it said it was packed with saw dust from the cabinet shop I took it out of.
 
SGBARRACUDA said:
After about 3 years use, I had to have the electric motor rebuilt which cost $125.00? and a new belt and that is it. I think if I recall it is a 1984 model.
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That not bad at all. You can find deals if you look and happen to have the cash. That last one always hangs me up. LOL
 
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