Announcement: Make your own silent air compressor

[dlilazteca]

I have not tried this but I am so tempted what do you guys think will this work what problems will I run into?

https://www.youtube.com/watch?v=9jOcLdZXRRs&feature=youtube_gdata_player

I also found this.
http://www.dakkadakka.com/dakkaforum/posts/list/505675.page

Carlos De La O III

 

[Beladran]

my stones are not big enough to monkey with an air compressor..
we had one blow up with enough force to move a 3000lb lathe = (

 

[dlilazteca]

But I would be using the components that are already on my compressor such as the cutoff valve, gauges the only difference would be air supply/ compressor

Carlos De La O III

 

[Tim Wells]

In short, I made one exactly like the guy in the video out of a tank I took off a cheap walmart compressor that the motor burned up on. I got the compressor from a discarded fridge and it worked fine. I'd make sure those hose clamps on that hose are good and tight so it stays on and you use properly rated hose. I blew up my first hose as soon as it turned on, those things are more powerful than they look. Proceed carefully and you'll be fine.

 

[JJ Roberts]

I have a Craftsman 30 gallon air compressor I drain it every two weeks had it for 20 years works great and its far away from the shop in the root cellar. How that for silent air. J.J.

 

[ED DELORGE]

Hello Carlos, I have put together two big compressors for my work, just like the video. All the parts are the same but larger. That looks like a fun project. I would build one myself if I had the time.

Ed

 

[monk]

i can see a possible problem for your air toys. the system is closed. the lost oil and condensate is going out to your air toys. if you do this, you better make sure the output is filtered really well. you want to catch the condensate, as well as the oil. this will bring havoc to certain of your air toys if not filtered properly. you may also be breathing the oil, no need to mention what that can do.

 

[dlilazteca]

i can see a possible problem for your air toys. the system is closed. the lost oil and condensate is going out to your air toys. if you do this, you better make sure the output is filtered really well. you want to catch the condensate, as well as the oil. this will bring havoc to certain of your air toys if not filtered properly. you may also be breathing the oil, no need to mention what that can do.

Hmmmm:what:

Carlos De La O III

 

[metalchipper]

i can see a possible problem for your air toys. the system is closed. the lost oil and condensate is going out to your air toys. if you do this, you better make sure the output is filtered really well. you want to catch the condensate, as well as the oil. this will bring havoc to certain of your air toys if not filtered properly. you may also be breathing the oil, no need to mention what that can do.

I agree with monk, In the tutorial link it reads you have to add oil to the compressor as it is expelled with the compressed air.
The compressor needs oil or it will seize up, it is not in a closed system any longer. Air and oil = not good---- for your use.
Have fun! Be safe.

 

[mitch]

Hmmmm:what:

Carlos De La O III

it just means you need to have good water & oil filters between the compressor and any equipment you're running with the compressed air. http://www.grstools.com/air-compressors/004-579.html

 

[bthomas]

I did not watch the video link (slow bandwidth).

Not endorsing or suggesting anyone play with pressure vessels . Buy these new direct from reputable manufacturers and your attorney will thank you should something go wrong. Scrounge /repurpose parts and you are on your own most attorney's won't want to take your case if you get injured.

But FWIW there must be some hillbilly in my past and I confess I have assembled 2 compressors using salvage refrig compressors. The motor/compressor unit has two steel lines. Shove the bare end of your wires into an outlet to test and you will find one steel line has suction when you put your thumb over the end and one is blowing. I brazed a nipple on the one that blows and then attached it to a complete salvaged compressor unit. The air blowing out should have minimal oil spray (hold open discharge line in front of a sheet of paper to check). If the video shows some sort of "soft air line" That might make sense as I can see where blowing a plastic or vinyl line would sure beat shrapnel from blowing a steel tank.

At this stage it is useful to drill a hole in the top of the sealed can (this will be your oil fill). Plug the hole with anything convenient (tapered dowel, cork etc). The plug doesn't have to be pressure tight there is no pressure in the can. You will use another longer dowel as a dip stick to monitor oil level since you won't have a nifty factory sight glass to monitor oil level...fill it to about 2" below the top. You should not have to add oil frequently. If you are using oil more frequently your compressor has a problem ...just scrounge another one [you should have identified this problem when you checked the oil spray pattern with the paper in front of the discharge line.]

#1 MOST IMPORTANT before attaching the discharge line to anything it is essential to wire your motor to the existing pressure switch controls. You are relying on the pressure control switch to limit the pressure. Your only backup is the safety blowoff valve. Identify both items on your donor compressor...if either looks at all suspect stop and find another donor. You may want to adjust the controls to turn on frequently but run briefly.

Pros: cost effective (if you find it cost effective to trade your time)

Cons: the refrig size 110 v compressors are not as large as the units that come from a factory assembled Silent Compressor. These are not rated for continuous duty so you may NOT want to place your refrig compressor onto a giant tank. As I mentioned I built 2 of these. The 1st I mounted onto a tank too large and did not have a oil fill hole and I damaged the compressor motor in 6 months time. [Over time it became "hard starting" and I would occasionally have to bang on the casing to get it to start]. At that time I remade the whole kit and made it with a much smaller tank , and reset the pressure switch so the compressor turns on and off more frequently rather than runs continuous for a long time to fill. And I added the oil fill hole. My 2nd unit was in service w/o issue for about 2 years.

Eventually I stumbled upon a factory SilentAir unit locally on C/L and bought it thinking at the time it would be vastly superior. It is a larger compressor motor but functionally I found it to be the same.

BTW from actual experience I did not add oil any more frequently than I add oil to a factory unit. IOW I found the amount of oil that actually enters the air stream is no different than a factory unit and the same separators are able to filter in the same manner

 

[ED DELORGE]

Hello bthomas, that was a very good post and you answered several questions that I had. I have a question or two for you.

First, how about the chips from drilling through the caseing? Do you need to worry about them?

2nd, would an air conditioner compressor work better?

Ed DeLorge

 

[bthomas]

Ed,

First---regards chips...I don't know if they are something to worry about or not...can tell you I did not take any special precaution and used an ordinary spiral twist drill bit which makes fairly good size chips. Would it have been better to use a high speed dental air grinder (like NSK) and make lots of little chips? Probably with care that could keep most of them out of unit that way but all I can say is I didn't give it a thought. Strike that .....makes me sound thoughtless ...lets say I did not over think it.

AFAIK the can is just a way to submerge the compressor in oil which cools and muffles it .

2nd, another question regards using A/C....again I don't know...I wanted convenience of 110v and "selected" my refrig compressor from a scrap pile. I would have been just as likely to scrounge a 110v A/C compressor if that had been on top of the pile.

On both I did remove them from the refrig units (the refrigerators at the scrap yard already had Freon or whatever gas "removed") but I was just selecting my candidates at random. They were sold to me at $0.30 a pound so it wasn't a big risk. Another source could be a used appliance shop...they might be able to comment on A/C vs. Refrig compressors ...relative size etc. and almost certainly would be able to tell you if the unit powers up (not something you know in advance when you shop at the scrap yard).

Bill