Air Compressor custom housing, cooling questions?!

[ClimberD]

Greetings,

Huge fan of this forum, long time lurker.

I have a 2 car garage (my happy place), setting it up for compressed air. I am a hobby mechanic, but it is turning into my living. My place is townhouse style, so I want to keep things quiet.

I bought an Ingersoll Rand, http://www.amazon.com/Ingersoll-P1IU-A9-Carry-Twinstack-Compressor/dp/B0035HYJN4/ref=sr_1_1?ie=UTF8&qid=1343515167&sr=8-1&keywords=ingersoll+compresor and even that is too loud for frequent use.

I will need to build a NOISE BOX .
Had idea to unbolt the compressor/motor and put it in a box made of this: http://www.homedepot.com/buy/building-materials-insulation-sheathings/1-2-in-x-4-ft-x-8-ft-temple-quietbrace-141134.html#.UBRqzrSe52A

Noise will be the easy part to control. Can put one box side on hinges, and line the edges with a gasket to seal air gap.

HOW DO I KEEP IT COOL?

Goals:
1) 15cfm (hopefully buy one big compressor on Craigslist)
2) Silence, hence the noise box...
3) Keep tight budget (can't afford to buy a $1000 Ingersoll Rand )

Ideas to keep it cool:
1) Submerge the compressor in fluid inside box? (oil, coolant, etc?)
2) Setup a cheap car-style fluid pump, move fluid out of the noise box and through a heat exchanger?
3) ??? How would you do it?

Many thanks in advance!

 

[chevelle67]

If you submerge the compressor and or motor in any fluid I can guarantee it will be the quietest one around. After 2 seconds of runtime it would get extremely quiet to point you would swear it's not even running.........

 

[ClimberD]

If you submerge the compressor and or motor in any fluid I can guarantee it will be the quietest one around. After 2 seconds of runtime it would get extremely quiet to point you would swear it's not even running.........

My biggest concern is the vibration, causing an improper build to fail, causing the seal around the compressor side to fail...

-Leaning towards antifreeze since nothing will corrode... I've never used it outside of a car, but will be mindful of material interactions.

-Is there any special reason the air line off the compressor to the tank is always a hard line? Would a soft line wear out with the pulsing? Because I could do a hard line into a small accumulator still inside the box, then a soft line off of that and onto the box-mounted bulkhead passthrough... Don't want to make it unnecessarily complicated, so hopefully that's not necessary.

-Will try to figure out which design will be better to seal up so liquid never touches the electric motor. Maybe it makes not difference since either way a compressor drive input shaft needs to be sealed... getting it all sorted out


Edit: After looking over my portable compressor, it appears a belt driven will be a lot easier to deal with.

 

[ClimberD]

Or could just put the compressor/motor in a fridge and turn up the thermostat to highest temp.
Air tight, on demand cooling, cheap (craigslist), and consequently a bit of a muffler!

 

[PT Doc]

Submerge compressor in fluid? What?

 

[Burgerkong]

Nothing wrong with that as long as it's something like mineral oil, look at the mineral oil submerged PC's.

 

[kursplat]

use a big ice chest

 

[mdbeck1]

My wife bought me a compressor for father's day. It came with mufflers for the input side. It was real quiet until I took one off.

Talk to a local compressor shop and see if they can order you some mufflers. I can have a conversation standing next to mine (80 gallon Kobolt).

 

[pipsters]

Most of the noise from a compressor comes from the air intake

 

[fourjeepin]

At my last house, I put the compressor in the HVAC closet in the garage. This closet was insulated and had an insulated door. It was so quiet! I wouldn't know it was on when using an air tool. After stopping the tool, you could hear it running. This is an oiled compressor. I had one of the oiless and it was deafening.

 

[pipsters]

Or could just put the compressor/motor in a fridge and turn up the thermostat to highest temp.
Air tight, on demand cooling, cheap (craigslist), and consequently a bit of a muffler!

That would work but the problem would be the wear on the pump from starting cold. Maybe use a good synthetic oil. At 40*F it's not too cold, anything below freezing and you might start having issues.

 

[slomatt]

The first compressor I owned was a Craftsman oil-less model that was extremely loud. I built a compressor shroud that gave roughly 6" of space on all sides of the compressor which is less than the minimum recommended space in the owners manual. The walls of the shroud were 3/4" melamine, 1.25" of foam on the inside, a layer of soundboard, and then two layers of sound deadening drywall on top of that (entire box weighs well over 200lbs). For airflow I placed a ~6" 120v fan at the bottom and built an exhaust muffler at the top.

I used this setup for about 5 years and with the fan running the compressor kept at a reasonable temperature. The shroud made a major difference in noise level, but never got it to be as quiet as the Kobalt oiled compressor I now use.

- Matt

 

[ClimberD]

You guys are awesome. The car forums I'm on probably wouldn't be anywhere near as helpful...

I do a little redesign work for aftermarket race parts, so heat is always on my mind, though it looks like I overdid it. Get the compressor some air flow, and it will be fine without a complicated setup of heat exchangers. My particular IR compressor is rated for continuous duty, so it most likely won't cook if I'm a little careful. Helps a lot to have fresh perspectives

Submerge compressor in fluid? What?

The aluminum / cast iron compressor body, of course not the electronics and motor

Nothing wrong with that as long as it's something like mineral oil, look at the mineral oil submerged PC's.

Wow, will read more about that for solid state electrical heat management issues. Still my IR portable compressor motor has a big fan mounted on the end... would make a freaking mess if the motor could somehow survive and run...

use a big ice chest

Good cheap air tight housing idea, thank you.

My wife bought me a compressor for father's day. It came with mufflers for the input side. It was real quiet until I took one off.

Talk to a local compressor shop and see if they can order you some mufflers. I can have a conversation standing next to mine (80 gallon Kobolt).

Most of the noise from a compressor comes from the air intake

NICE! will order a intake muffler / silencer first! I just popped the filter off my compressor, made almost no noise difference. If there is not one to buy, I can just make one

That would work but the problem would be the wear on the pump from starting cold. Maybe use a good synthetic oil. At 40*F it's not too cold, anything below freezing and you might start having issues.

Manual said range was 32-100*F, ideal being 70*. I wonder how hot I can get a fridge to run... maybe increase resistance to the sensor to fool it... Now I'm over-complicating things again, maybe. It does run synthetic, comes in the box, but I'm with you on wanting to get max ring seal life out of it, so 70*+ it is if I can help it.

The first compressor I owned was a Craftsman oil-less model that was extremely loud. I built a compressor shroud that gave roughly 6" of space on all sides of the compressor which is less than the minimum recommended space in the owners manual. The walls of the shroud were 3/4" melamine, 1.25" of foam on the inside, a layer of soundboard, and then two layers of sound deadening drywall on top of that (entire box weighs well over 200lbs). For airflow I placed a ~6" 120v fan at the bottom and built an exhaust muffler at the top.

I used this setup for about 5 years and with the fan running the compressor kept at a reasonable temperature. The shroud made a major difference in noise level, but never got it to be as quiet as the Kobalt oiled compressor I now use.

- Matt

Matt, wow... questions: did the fan in the bottom **** air from outside the box? In other words how did air get into the box to then get out through the exhaust muffler? This interests me, as I've spent a ton of time learning to silence LOUD engines, sure it's all similar tricks. Thinking I would just double the parts shopping list for the exhaust muffler, so intake through one muffler system, out the other, plus fan(s). Not sure it's any cheaper than a fridge... but might be the more sane route to go if the compressor intake muffler does not achieve the goal...

 

[ClimberD]

Just ordered this: http://www.amazon.com/Solberg-FS-06-050-Miniature-Silencer-Compressors/dp/B00153AIMQ/ref=sr_1_1?ie=UTF8&qid=1343550565&sr=8-1&keywords=FS-06-050
Solberg FS-06-050, Miniature Filter Silencer/Breather for Compressors & Blowers, 1/2" MPT,10 SCFM

If $23 shipped for a better silencer filter is really all it takes, I'm going to be in hog heaven.

Knowing it's simple/cheap/available 1/2" NPT, I can also throw together a muffler to go between this silencer and the head, depending on how quiet this silencer is first.

Added silencer to put on after this Solberg filter would be something like this since it's so cheap and I have a 1/2" npt tap, or could find some other way to get it to connect in line pretty easy. http://www.amazon.com/Briggs-Stratton-89966-Muffler-Horizontal/dp/B0038U3KVU/ref=sr_1_28?ie=UTF8&qid=1343551660&sr=8-28&keywords=1%2F2+npt+muffler

 

[PT Doc]

The highest db noise from some compressors is from the air intake. If you put an intake silencer on the intake, you might be surprised at how little it did since the next loudest noise is quite high tis is likely the electric motor.

Building an enclosure is really the best options or ultimate quiet. Is your compressor noise lower when you are outside the garage around the corner? Of course it is, because the garage serves as a sound enclosure. Now, go build yourself an enclosure and post photos of what you built long with pre and post dba levels.

 

[Burgerkong]

I know Bel-Aire has models with a shroud on the motor/pump.

 

[mdbeck1]

Additional ways that I silenced my 80 gallon Kobalt...

First... the compressor came with inlet mufflers. I ran it without the mufflers and it was VERY noisy.

Second... I built a "closet" about 36 X 36. I insulated all three walls. The closet was 8 feet tall so I built a shelf and installed a an old central air blower motor (air flow is down toward the top of the compressor). The motor helps keep the compressor cool. I also put a door on the "closet".

The top of the closet (intake for the central air blower motor) has a furnace filter on it. This helps filter the smoke and dust out of the air.

The door of the closet (exhaust for the central air blower motor) has a furnace filter on it. So when I get smoke, sheetrock dust, sawdust, ... in the air I get double filtered air.

The central air blower motor is noisier than the compressor. I can actually stand next to the compressor and have a "normal" conversation. If I were to insulate the door more it would be even quietter.

 

[ClimberD]

Thanks guys, interested to see how this turns out. I also found exhaust mufflers for the compressor output, no idea much that would help... will put a screwdriver on every part of the assembly to see what's resonating and what's not as much. Will be hard to tell since the vibration is so intense.

 

[ClimberD]

Held my hand over the compressor inlet, and it cut noise down by maybe 30%... as where the IR filter canister only cut down the noise level slightly. So yes I'm going to build a box out of sound board.

One idea I had for sound box heat management is to have the compressor output line plumbed immediately outside the box, so the heat from the immediate compressed air itself will radiate outside of the box instead of inside it. That leaves internal compressor heat transfer, drive friction and motor heat. I'll be interested to measure box temperature...

Will post pictures

Had a separate idea for an air dryer, for later. Could plumb the compressor air inlet tube through a small fridge. Have not settled on the details of the design, though I have lots of ideas. One thing I like about this is it would feed the compressor 40* cooler, denser, dryer air, but the compressor itself would still be at or above garage ambient temperature.

In short, mini fridge LOADED with as much heat capacity material as possible so I can get the longest duration of cooling before the ambient garage air warms up the fridge temp. So big picture, air would go: Garage ambient air (70-74*F air conditioned and dehumidified to 40%) > filter/silence > through pre-cooler inside fridge > conventional air dryer while still cold > compressor(s) > tanks > regulator > tools.

Cheap parts, simple, should be great for intermittent use. Also means no further upgrades except an additional final bead dryer and a final .5 micron filter would be needed for painting, bead blasting, etc.

I like this enough that I am interested in buying another IR portable air compressor for parallel hookup. Only bad thing about it is the direct drive, but in turn it's compact and portable for if ever I do a job off site.

 

[EOC_Jason]

Most of the noise from a compressor comes from the air intake

Look at the Solberg silencer filters, you can get them on Amazon. You can upsize it too and just get pipe fittings to adapt it.

Also people say to put at least two 90's in the intake line to help reduce noise. Haven't tried this myself yet but thought I would pass it along.

If you are going to get a new compressor, pay attention to the PUMP RPM... The slower the better... But with your budget you probably won't be able to be picky.

 

[ClimberD]

Solberg Filter arrived today! Was surprised, it's half the size as the OEM Ingersoll Rand filter assembly. Though its CFM spec is still double the compressor, so no concern there.

Made NO DIFFERENCE!!! I switched them back, forth, back, forth, back, forth, absolutely zero difference.

Thus, the OEM Ingersoll Rand filter happens to be a silencer as well.

Yup going to build a box. I'm going away, back Wednesday. Will build it after then.

Anyone want a 1/2" NPT silencer filter?

 

[PT Doc]

I think that you kind of knew that it wouldn't make a big difference going in. I would guess 3dba drop. Not very noticeable to the untrained human ear.

 

[pipsters]

Solberg Filter arrived today! Was surprised, it's half the size as the OEM Ingersoll Rand filter assembly. Though its CFM spec is still double the compressor, so no concern there.

Made NO DIFFERENCE!!! I switched them back, forth, back, forth, back, forth, absolutely zero difference.

Thus, the OEM Ingersoll Rand filter happens to be a silencer as well.

Yup going to build a box. I'm going away, back Wednesday. Will build it after then.

Anyone want a 1/2" NPT silencer filter?

I have that same silencer (that came stock) on my Craftsman compressor. I think they are meant to silence an open air motor not replace something you already have.

You are on to something with running the compressed hot air line out of the box, cooling it, then back into the box. Would make the box a lot easier to cool.

 

[ClimberD]

Going to draw up plans. I'm more of a car person than carpenter, don't know much about wood and making boxes. I read up on some acoustical forums, have some general ideas about designing the quietness into it.

 

[ClimberD]

Very rough, very basic, no dimensions (maybe 5' wide, half as tall and deep, can draw up later). Already I see changes to make.

What I would change is putting the back-and-forth vents on the outside of the double wall box, and maybe have the vent holes be offset between the inner and outer layer, so inner layer vents would be near the ends of the box, while outer layer ports would be in the middle. Then proceed with exterior zig-zag baffles.

Pictured:
1)Ambient air getting drawn in from underneath (box will be on casters), and hot exit would be up, hopefully keeping the two apart.
2)I like that the baffles are in back, out of the way.
3)Floating compressor mount base on some sort of vibration-isolating stand, maybe rubber blocks if cheap? Don't know how best to suspend the deck from inner box, and inner box from outer box... depends on how strong the quiet brace sheathing is.

Everything except compressor/motor bodies and electric boxes will be outside the box. Air tanks will be near by after the dryer.

Not Pictured:
1: Both top layers of the box would be hinged, so swing open outer door, then inner door, and you're in. Foam gaskets to seal air gap.
2: Fan. Fan would be mounted inside the box, pulling out the hotside, not sure where, but that's not critical (probably sitting like a 5th compressor in a row. Would love a heat-sensing attic fan if cheap. Compressor motor fans will create plenty of turbulence, so attic or bathroom fan only needs to flush out the box frequently.
3: One pipe in (filtered), one pipe out (compressed air), both through bulkhead fitting and rubber connections, quick connects.

Optional:
Stuff air gap between two boxes with rockwool (Roxul Safe'n'Sound).

Am I missing anything?

 

[slomatt]

Matt, wow... questions: did the fan in the bottom **** air from outside the box? In other words how did air get into the box to then get out through the exhaust muffler? This interests me, as I've spent a ton of time learning to silence LOUD engines, sure it's all similar tricks. Thinking I would just double the parts shopping list for the exhaust muffler, so intake through one muffler system, out the other, plus fan(s). Not sure it's any cheaper than a fridge... but might be the more sane route to go if the compressor intake muffler does not achieve the goal...

The fan on the bottom sucked air from outside of the box. My thinking was that since heat rises I wanted the cold side to be at the bottom and the hot side to be at the top so that the fan wasn't fighting against the convection currents. Originally I was going to put a baffle on the fan input, but it turned out not a lot of noise was escaping, possibly because the fan was pushing air in. I did put a baffle on the air output which made a big difference in sound level.

Here's a quick picture of the inside of the shroud with the front wall removed. The fan is in the lower right, and no the wiring is not up to UL code but I unplugged it when not in use. I installed a sliding door on the front wall so I could reach in to drain the tank.

- Matt

 

[ClimberD]

Thanks Matt,

It's not so much the air movement as the fan itself that reduces sound transmission. Like how turbos reduce exhaust noise. That is a good idea right there, fan(s) as part of overall noise control strategy.

 

[mayday0017]

Looks like a lot of work, I prob would of just sold compressor and bought a used OILED compressor off Craigslist making it an even trade. The oiled compressor would prob be as quiet as you will ever get this setup & it is much nicer having it out in the open to move around when needed and peace of mind it won't over heat.

 

[pipsters]

Looks like a lot of work, I prob would of just sold compressor and bought a used OILED compressor off Craigslist making it an even trade. The oiled compressor would prob be as quiet as you will ever get this setup & it is much nicer having it out in the open to move around when needed and peace of mind it won't over heat.

I agree way too much work. 120v belt driven compressors run fairly slowly and are pretty quiet. I bet you're looking at $150 in materials when its all said and done plus time and hassle.

 

[ClimberD]

Just saw a $530 Puma 12cfm@90psi 60gallon at Northern Tool, that changed everything.

To review, I have an Ingersoll Rand 4.2cfm direct drive compressor, Oiled, reviewed to be quieter than almost all but maybe the Makita 2400.

$530 is a whole different story than $1300.

I also found on NT 16 or 18 cfm for $900? Or so? Single stage 230v models, with warranty.

Only thing I really don't like is the 50% duty cycle on almost everything <$1000. Can't find much info on making that closer to 100%. Really open to any modification to dissipate the heat better. More fans would be easy. I wonder if my (serious) idea for DIY precooler & aftercooler refrigerator would make a big difference in head temperature. Could test it easy with K-type thermocouple or infrared thermometer.

I need to buy something next week. Still have time to return my Ingersoll Rand baby compressor.

 

[shoot summ]

Solberg Filter arrived today! Was surprised, it's half the size as the OEM Ingersoll Rand filter assembly. Though its CFM spec is still double the compressor, so no concern there.

Made NO DIFFERENCE!!! I switched them back, forth, back, forth, back, forth, absolutely zero difference.

Thus, the OEM Ingersoll Rand filter happens to be a silencer as well.

Yup going to build a box. I'm going away, back Wednesday. Will build it after then.

Anyone want a 1/2" NPT silencer filter?

My experience as well, saw everyone touting the Solbergs, bought them and it made no difference.

 

[pipsters]

Just saw a $530 Puma 12cfm@90psi 60gallon at Northern Tool, that changed everything.

To review, I have an Ingersoll Rand 4.2cfm direct drive compressor, Oiled, reviewed to be quieter than almost all but maybe the Makita 2400.

$530 is a whole different story than $1300.

I also found on NT 16 or 18 cfm for $900? Or so? Single stage 230v models, with warranty.

Only thing I really don't like is the 50% duty cycle on almost everything <$1000. Can't find much info on making that closer to 100%. Really open to any modification to dissipate the heat better. More fans would be easy. I wonder if my (serious) idea for DIY precooler & aftercooler refrigerator would make a big difference in head temperature. Could test it easy with K-type thermocouple or infrared thermometer.

I need to buy something next week. Still have time to return my Ingersoll Rand baby compressor.

To step up to 100% duty cycle you are looking at a pump needing a pressurized oil pump on it.

You can run those ones over 50% you just have reduced life with them. On my compressor the duty cycle is limited over the course of an hour, and it recommends a 50%-75% duty cycle so 30 to 45 mins per hour. Unless you are doing extremely ********* sand blasting or sanding you won't be running it that continuously. You're a home guy not like it's at a shop running 12 hours a day constantly.

A pump rated for say 20,000 hours, maybe cut in half at worst, 10,000 hours. That is 14 years @ 2 hours a day. That's a pretty long lifespan and that is even if you run it constantly for 2 hours a day which I doubt you will.

The head temp won't be reduced with an aftercooler. That reduces temps from the pump into the tank. It's very effective though. Just keep in mind that heat will radiate into your garage.