Sound dampening options for a compressor

[Steve Middleton]

I bought a "shop vac" filter and added in line with the small, 4"(?) stock filter using plywood, silicone, and all thread. It made a BIG difference eliminating most/all of the higher pitched noise. YEMV

[Charles Lent]

I ended up adding a 6 X 6' shed to one side of my shop for my 80 gallon 14 cfm compressor. The shop wall between the compressor and my shop is an insulated stud wall, but not the studded walls of the shed and this shed is not heated or air conditioned, but North Carolina Weather isn't likely as severe as most of you deal with. Access to the compressor is from outside the shop and the noise level from the compressor inside the shop is very low. I can hear it when it is running if no woodworking machines are running, but it is not objectionable. There is one 6 X 12" air vent grill under the eave to let air out of the compressor shed and a second one down near the floor to let outdoor air in. I placed them this way to convection ventilate the shed of compressor heated air during the warmer months of the year. It is very rare that our Winter here remains below freezing for any length of time. It usually goes a little below freezing during the night and then is well above freezing in the afternoon, so I just use synthetic oil in the compressor and have not had any problem at all with it. The air vents seem to work well during the warmer months when the daily temperature is 90 - 100, keeping heat from building up within the compressor shed. I had a remote reading thermometer watching it for the first year, but it never ran more than about 10 degrees above ambient, so I no longer monitor it.

This set up may or may not be best for you if you live in colder climates, but it seems to work well for me here in NC. Putting the compressor in it's own space outside, but connected to the shop made a huge difference for me in shop noise level. It's also located on the North side of the shop where it faces a lake and not my home or the neighbor's homes. It's been there for 17 years and no one has complained yet.

Charley

[Keith Downing]

I ended up adding a 6 X 6' shed to one side of my shop for my 80 gallon 14 cfm compressor. The shop wall between the compressor and my shop is an insulated stud wall, but not the studded walls of the shed and this shed is not heated or air conditioned, but North Carolina Weather isn't likely as severe as most of you deal with. Access to the compressor is from outside the shop and the noise level from the compressor inside the shop is very low. I can hear it when it is running if no woodworking machines are running, but it is not objectionable. There is one 6 X 12" air vent grill under the eave to let air out of the compressor shed and a second one down near the floor to let outdoor air in. I placed them this way to convection ventilate the shed of compressor heated air during the warmer months of the year. It is very rare that our Winter here remains below freezing for any length of time. It usually goes a little below freezing during the night and then is well above freezing in the afternoon, so I just use synthetic oil in the compressor and have not had any problem at all with it. The air vents seem to work well during the warmer months when the daily temperature is 90 - 100, keeping heat from building up within the compressor shed. I had a remote reading thermometer watching it for the first year, but it never ran more than about 10 degrees above ambient, so I no longer monitor it.

This set up may or may not be best for you if you live in colder climates, but it seems to work well for me here in NC. Putting the compressor in it's own space outside, but connected to the shop made a huge difference for me in shop noise level. It's also located on the North side of the shop where it faces a lake and not my home or the neighbor's homes. It's been there for 17 years and no one has complained yet.

Charley

Thanks for the thorough response Charley. My only concern, other than the obvious costs involved, of building a room for the compressor outside was moisture buildup in the humid months. With no airflow at all I worry it could be problematic over a few years. Have you noticed anything like that?

[Charles Lent]

Where I am located, the Summer month high temperatures are usually in the 90's, but the humidity is usually in the 50-65%. My shop is located about 10' above and about 80' from a 250 acre lake. When the compressor is running extensively, the shed that it is in will increase in inside temperature by about 10 degrees, but the low and high vents cause enough convection circulation of the air to keep it from getting any hotter. The air is drawn in the lower vent, rises as the compressor heats it, and then exits from the high vent. The compressor shed is attached to the North facing wall of my shop, so it never sees direct hot Sunlight. In the colder months the temperature goes below freezing most nights, but only very rarely reaches zero F. If the following day is sunny, the afternoon temperatures will be above freezing, usually in the 40-50 range. We get snow occasionally, but more likely ice storms. Using synthetic oil in my air compressor it always starts easily on the coldest days and runs well on the hottest days here.
I change the oil every spring, just because, but it likely could go several years before needing changing. I'm not a very heavy compressed air user, but have the large air compressor to do sand blasting and painting occasionally. When doing these, I have a refrigerated air dryer that removes the moisture from the compressed air. Otherwise It just goes through a filter and regulator and then into my shop air lines. I have a condensate accumulator attached to the bottom drain port of the tank and it's outlet is piped out through the wall of the shed and down toward the ground. I periodically open a ball valve in this line and the air pressure blows the condensate out of the accumulator. I haven't made any changes to my compressed air system in the past 10 years or so. It is serving my needs just fine. For portable use I have a pancake style 4.5 cfm Junn-Air compressor to run my nail guns, etc. It's about as loud, when it runs, as a refrigerator. I also have an old 20 gal 2 hp air compressor in my garage for when I'm repairing one of my vehicles, because my garage and wood shop are on opposite sides of my property. It too, gets synthetic oil and sits inside the garage which shelters it from the rain and Weather, but not the temperature cycles here. I hope this answers your questions.

Charley