Quieting an air compressor?

[Brad54]

I've heard that most of the noise we hear from an air compressor is generated by the intake side of the head, and that good air cleaner assemblies will quiet it down some.

What about routing a automotive muffler to the air intake side of the compressor and capping it with and air cleaner?

-Brad

 

[AussieDan]

1 or 2 90 degree bends on the inlet will cut the noise a lot, I made this adapter to put a Solberg intake filter/silencer on my craftsman and it made a big difference from the stock foam filter.



I was thinking about adding another 90 to see if it quieted it down any more, but haven't gotten around to it.

 

[theoldwizard1]

If you want to make it quiet, put it in a box.

Well not a 4 sided box with a lid ! Build 3 sided box using 2x2 framing. Do NOT attach it to the floor or to any other walls so that it can be easily moved out of the way to service the compressor. You need about a 6-12" gap all around the bottom. Leave the top OPEN. The sides need to go about 12" above the top of the compressor, plus you need at least 1-2' of space above that before you reach the ceiling. The sides can be something like 7/16" OSB as long as the frame you build is strong enough to with stand occasional moving.

The real trick is to line the box with 4" of foam board. Also make certain that there is a good 12" between the hot parts of the compressor (pump, motor) and the foam board. You might consider the foil faced foam board.

Oh yeah. If you have an upstairs, this will not help them!

 

[mdbeck1]

For Father's day SWMBFAO bought me the 80 gallon compresser from Lowes. It came with two air intake filters. They look like miniature automotive intake air breathers. I turned the compressor on with one of them off and it was REAL loud. Later I put it back on and ran it. MUCH QUIETER.

I finally got it placed and ended up having to put a 90 degree "street elbow" on it to save a little bit of room. It still works just fine.

 

[Brad54]

I ask because I'm in the (long, drawn-out) process of getting a huge 10hp 120-gallon LeRoi compressor. It won't fit in my shop. Correction: I don't WANT it in my shop. So I'm going to build a shed for it outside. I like my neighbors, so even though it will be in an enclosed shed, I want it as quiet as possible for them.

-Brad

 

[930dreamer]

I ask because I'm in the (long, drawn-out) process of getting a huge 10hp 120-gallon LeRoi compressor. It won't fit in my shop. Correction: I don't WANT it in my shop. So I'm going to build a shed for it outside. I like my neighbors, so even though it will be in an enclosed shed, I want it as quiet as possible for them.

-Brad

Can you post some pics?

 

[A_Pmech]

I would add a compressor intake silencer. That's what I intend to do with my Quincy 5120, even though it will be in a separate concrete building. In my case, I need two!

http://www.solbergmfg.com/ViewSeriesDetail.aspx?SeriesId=12&src=drill

http://www.vanec.com/Reciprocating.Htm

 

[Brad54]

Can you post some pics?

No. The compressor is in storage, and I don't have good access to get a pic.

The pump model is 550A, with a GE 300 line control box.

According to LeRoi, the 10hp motor runs the pump at 1250rpm, 7.5hp runs it at 860rpm and the 5hp runs it at 570rpm.

-Brad

 

[Falcon67]

YMMV on the air filter - see this thread, post #40 in particular.
http://www.garagejournal.com/forum/showthread.php?t=25979&highlight=sound+compressor&page=2

I would plan on a sound deadening box as a complement. The air filter may work for you, but may not. Just so you know it's not a given.

 

[HAP]

The slower the compressor turns, the quieter it will be with extended longevity. However the low rpm models cost a bit more.

 

[NewShockerGuy]

1 or 2 90 degree bends on the inlet will cut the noise a lot, I made this adapter to put a Solberg intake filter/silencer on my craftsman and it made a big difference from the stock foam filter.



I was thinking about adding another 90 to see if it quieted it down any more, but haven't gotten around to it.

What size is that solberg housing and filter? I have a 1/2" on my husky and it looks identical to yours however I only have one inlet hole and your's looks like it has at least two... Just wondering if this is due to say if you have 3/4" filter..etc.

Thanks,
-Nigel

 

[koditten]

I'm betting this compressor is fairly quiet to begin with. If you slow it down a bit with a different pully, its gonna be quieter yet. I bet an intake silencer will make this thing nice and quiet. My antique Quincy (sirca 1926) was nice and quiet. I sure miss that thing. Some day I will by a new tank and get it going again.

 

[Stuart in MN]

A 10hp motor is most likely going to require three phase power (there are 10hp single phase motors, but I've never seen one.) Before you go any further make sure you can run the thing in your shop.

 

[mdbeck1]

For Father's day SWMBFAO bought me the 80 gallon compresser from Lowes. It came with two air intake filters. They look like miniature automotive intake air breathers. I turned the compressor on with one of them off and it was REAL loud. Later I put it back on and ran it. MUCH QUIETER.

I finally got it placed and ended up having to put a 90 degree "street elbow" on it to save a little bit of room. It still works just fine.

A further note on this one. Since receiving it I have made a "closet" for it in the garage. Three sides are insulated, the top is insulated, the feet are attached to hockey pucks, and I'll be putting a door on it soon. There's a bathroom on the other side of the wall from it and you can hear it but it's not too irritating. Kind of like the CH&A unit coming on.

I also was a little bit worried about heat build up so I put an old CH&A motor above it (blowing down). The air will come IN from the garage through a filter and will vent OUT through a filter in the front door. I'm also thinking about putting a temperature gauge in the closet so that I can monitor the heat.

 

[Brad54]

A 10hp motor is most likely going to require three phase power (there are 10hp single phase motors, but I've never seen one.) Before you go any further make sure you can run the thing in your shop.

It is 3ph... I'm looking at motors this week: one to replace the burned out one on the unit, and another to make a phase converter. (I've also got a lathe and will have a bridgeport one day, so the phase converter makes sense)

The compressor is NOT quiet as is... I was in the shop with it frequently, and you couldn't have a conversation with YOURSELF once the thing kicked on.

But it recovers very quickly, and has a huge tank.

For the price of a new motor, a phase converter, an outside shed on the shop and a bunch of aggravation, I'll have a kick-*** compressor.

Or, for $800-$1200, I could get a smaller one that's probably not made in America, and plug it in.

-Brad

 

[koditten]

I just checked Grainger real quick and I found a 7.5 1p. and a 5 1p. 800 bucks and 600 bucks. They have always sold to me at below book price.

What kind of money is involved for a phase converter? I've only heard that they are not cheap. Don't know much about them.

 

[930dreamer]

It is 3ph... I'm looking at motors this week: one to replace the burned out one on the unit, and another to make a phase converter. (I've also got a lathe and will have a bridgeport one day, so the phase converter makes sense)

The compressor is NOT quiet as is... I was in the shop with it frequently, and you couldn't have a conversation with YOURSELF once the thing kicked on.

But it recovers very quickly, and has a huge tank.

For the price of a new motor, a phase converter, an outside shed on the shop and a bunch of aggravation, I'll have a kick-*** compressor.

Or, for $800-$1200, I could get a smaller one that's probably not made in America, and plug it in.

-Brad

Is this for a home garage or a shop? Building a rotary phase converter can be intimidating but you can do it. Since you want to add a bridgeport mill in the future go for it. A variable freq drive (vfd) is common for 2 hp or less three phase equipment (Bridgeport).

The only limiting factor I see is the availability of a 50-70 amp circuit.

Look in the Practical Machinist forum under transformer, rpc, vfd's.

 

[Torque1st]

YMMV on the air filter - see this thread, post #40 in particular.
http://www.garagejournal.com/forum/showthread.php?t=25979&highlight=sound+compressor&page=2

I would plan on a sound deadening box as a complement. The air filter may work for you, but may not. Just so you know it's not a given.

I think Falcon was trying to win an argument and not trying very hard to really test an intake filter. As others have reported here an intake silencer makes a big difference.

When building a box around a compressor airflow is important as is a labyrinth style baffle system with sound absorbing materials. There are many companies that specialize in industrial sound reduction techniques and materials. Visiting their websites may help with designs and techniques. I am not an expert in sound reduction but I have designed a number of successful sound reducing systems for industrial machinery. European requirements for noise levels on the factory floor are incredible but I was able to meet them even for high speed hydraulic punch presses and other machines.

 

[Torque1st]

I just checked Grainger real quick and I found a 7.5 1p. and a 5 1p. 800 bucks and 600 bucks. They have always sold to me at below book price.

What kind of money is involved for a phase converter? I've only heard that they are not cheap. Don't know much about them.

There is a lot of info on Rotary Phase Converters (RPC's) and Variable Frequency Drives (VFD's) here:
http://www.practicalmachinist.com/vb/forumdisplay.php?f=11

 

[Brad54]

Is this for a home garage or a shop? Building a rotary phase converter can be intimidating but you can do it. Since you want to add a bridgeport mill in the future go for it. A variable freq drive (vfd) is common for 2 hp or less three phase equipment (Bridgeport).

The only limiting factor I see is the availability of a 50-70 amp circuit.

Look in the Practical Machinist forum under transformer, rpc, vfd's.

I'm a full-time freelancer writer for car magazines. I've got four full-blown project cars, my wife's daily driver is a '61 Corvair wagon and my daily is a '61 Chevy Suburban.

So it's not a "shop" per se, in that I don't do commercial work for customers out of it.

But it's a shop in that I do more than the average guy out there. I'm trying to be out there every day doing SOMETHING. The big-*** compressor will help, because there's always bead blasting and painting to be done. ALWAYS.

(I actually have a friend who just started a real shop, doing repair and restoration work. I have more tools and equipment than he does.
By a long way.)

The shop has it's own 200amp service with independent meter.

-Brad

 

[Stuart in MN]

The trick with a sound enclosure is that it needs to allow enough air to flow for the compressor inlet as well as for cooling purposes. I would try to come up with a labyrinth for the passage of air into and out of the shed or enclosure. Here are a couple examples, one is for a shop vac and the other is a box for a small compressor inside a shop, but they show the general idea of how the air has to flow back and forth through sound insulated passages that will dampen the noise.

http://home.comcast.net/~prestondrake/Stuff_Workshop_shopvacsilencer.htm

http://www.cianperez.com/Photo/Expo...ssor_Enclosure/Pages/Compressor_Enclosure.htm

 

[rodm1]

You can hang a piece off sound deadening materiel in front off the compressor and that will help quit a bit. My box is in front of the compressor and I open the top when its running and that help a lot to.

Try hanging and moving around some sound deadening materiel. You might just find that will be satisfactory.

 

[Torque1st]

You can hang a piece off sound deadening materiel in front off the compressor and that will help quit a bit. My box is in front of the compressor and I open the top when its running and that help a lot to.

Try hanging and moving around some sound deadening materiel. You might just find that will be satisfactory.

Even a piece of carpet will help some.

 

[AussieDan]

What size is that solberg housing and filter? I have a 1/2" on my husky and it looks identical to yours however I only have one inlet hole and your's looks like it has at least two... Just wondering if this is due to say if you have 3/4" filter..etc.

It's a 1", 1/2" would have been smaller cross sectional area than the intake port on my compressor.

To make the adapter I started by cutting a flange out of a piece of scrap steel, then cut down a pipe ******, ovalized the end and welded it to the flange.

The ovalized 1" pipe turned out to be a perfect match for the intake port, so I went with a 1" filter/silencer since the price difference between 3/4" and 1" was negligible (hooray ebay ). It has 3 equally-spaced intake holes.



Dan

 

[incurablescrounge]

A friend of mine mounted his compressor on rubber isolated studs and put an automotive exhaust muffler on the intake. He just attached the air filter to the muffler. I can't get pics but it sure did run quiet.

 

[noboD]

Brad, I have a 5 hp upright in my shop. I ran a 2 inch pvc pipe from the original inlet up above my suspended ceiling for the intake and placed a car air cleaner on top for a filter. Elements are still available and it runs MUCH quieter. Bring the long legged school teacher to Hershey and I'll show it to you. The rubber feet help too.

 

[TWX]

Don't forget about bushings between the compressor and the concrete lab and anchors. that'll reduce the amount of vibration in the slab, so the slab itself won't resonate as much.

I used old hockey pucks. My compressor is a little light compared to the hardness of the pucks, but they'd work very well on a heavier unit.

As for quieting, older auto-style air cleaner pan assemblies with snorkels work quite well on cars and should work well on an air compressor...

 

[hammerhead611]

Routing an automotive muffler will silence your air compressor for sure. Or even extending the air intake valve to outdoors using an air hose(as the exhaust valve is the main culprit most of the times)? If not, then you're missing a golden chance. You can drill a hole to a nearby wall and pass an air hose which should be connected to air intake valve and left open on outdoors the other side.

Only 8 years late to the party...

 

[kbs2244]

A small car muffler plumbed into the intake is the usual way for those that cannot build a closet.

 

[rburke65]

Wow....2011 original post....maybe these posts could drop off after ..???... 5 years. Or how about a pulsing “year” alert after a few years to bring to our attention that this is an ancient post.

 

[BajaScout]

Don't forget about bushings between the compressor and the concrete lab and anchors. that'll reduce the amount of vibration in the slab, so the slab itself won't resonate as much.

I used old hockey pucks. My compressor is a little light compared to the hardness of the pucks, but they'd work very well on a heavier unit.

As for quieting, older auto-style air cleaner pan assemblies with snorkels work quite well on cars and should work well on an air compressor...

Did the hockey pucks hold up?


Sent from my iPhone using The Garage Journal mobile app

 

[marinusdees]

In general, compressors don't like phase converters Dunno if this general statement applies to VFDs.

 

[rick carpenter]

Brad, I have a 5 hp upright in my shop. I ran a 2 inch pvc pipe from the original inlet up above my suspended ceiling for the intake and placed a car air cleaner on top for a filter. Elements are still available and it runs MUCH quieter. Bring the long legged school teacher to Hershey and I'll show it to you. The rubber feet help too.

From what I've read and tried trying to quieten my little 8gal you can't do much more on the unit than what the factory provides. I'd think an insulated enclosure and/or a remote intake like noboD has with a section of maybe auto radiator hose would do the most.

 

[JRC3]

I order my compressed air through Amazon, couldn't be more quiet. Order enough and get free delivery. You just gotta watch out for that imported counterfeit stuff.

 

[aka Larry]

I order my compressed air through Amazon, couldn't be more quiet. Order enough and get free delivery.

I did the same, but I had to return it. For some reason it wouldn't fit in the original box though.

 

[mike93lx]

Wow....2011 original post....maybe these posts could drop off after ..???... 5 years. Or how about a pulsing “year” alert after a few years to bring to our attention that this is an ancient post.

Why? Is there no value to people seeing previous discussions? Why always start from scratch?

 

[JRC3]

Why? Is there no value to people seeing previous discussions? Why always start from scratch?

When I first found the forum it was while looking at mid-lifts. Went through every old post I could find with them. Made me join the forum.

The archives give this place more value.

 

[Citation]

Wow....2011 original post....maybe these posts could drop off after ..???... 5 years. Or how about a pulsing “year” alert after a few years to bring to our attention that this is an ancient post.

See that Lucifer quoted post a few up? It's a spam poster that brought this back to life.

 

[mgent]

I'm glad the page came back up, as the link to the 'cianperez.com' compressor box looks like a great solution... Depending on which compressor I end up buying I'd plan to build something similar, but with a few minor changes:
- sound deadening material lining the 'face' of the exit/inlet pathways - why just the sides in the example?
- sound deadening material lining the inside of the box
- A switch or two to turn compressor and fan on/off when not in use
- 'finish' the exterior with drywall and paint to match the rest of the garage...

 

[Slednut]

My old compressor was outside, a month ago I bought a new one and put it inside and made a box around it. It's OSB with two layers of sound board on the inside.

It has venting going through 4 inches of foam. It sounds like a car idling, you can have a conversation next to it without a problem. If I'm going to do something where it's going to run a lot I remove the top which isn't screwed down.