Page 1 of 3

1000 psi Air compressor project!!

Posted: Tue Feb 01, 2011 9:42 pm
by BigBang J
Hey guys, Here is my first project posting, ya'll have probably been wondering if I was ever going to do anything besides ask questions :)
Well I finally got my hands on a mini fridge that had a refrigerant leak, so I removed the compressor and turned it into a high pressure air compressor.
When I cut the refrigerant line hardly any gas came out since it mostly all leaked out already. It probably cost me about $35 to build.
I was hoping to get at least 700psi and was really hoping for 800, but when it hit 1000psi! Wow I am like so happy:)
And actually it was still slowly but steadily climbing at 1000! But 1000 is enough for me, besides I don't trust the copper tubing for much over that.

Here is a parts list:

Various brass fittings ( some of which I had already)
a 1/8" brass check valve from McMaster Carr (which I had already)
4' of copper tubing for the radiator
a needle valve to de pressurize the line (which I had already)
a pressure regulator for the pressurized inlet, that way I don't have to readjust my other compressors reg every time
a 1000 psi gauge off ebay for $10
A paintball 1/8" quick disconnect for a c02 line $5 off ebay
All the wood and hardware I found laying around my shop.


Well it isn't completely finished, since it runs 1000psi I went ahead and soldered all my fittings together. So I am now giving it the stress test, holding 1000psi
overnight, I already found a few weak spots in my soldering that I had to repair (thin spots in my solder that started leaking after a 5- 10 minutes holding pressure).
And eventually I will give it a paint job and fill in my imperfect holes and such. Well enough talking here IT IS!

Posted: Tue Feb 01, 2011 9:49 pm
by POLAND_SPUD
Nice
My simple copper radiator. I hoped it would also help contain the oil to reduce the amount that comes out
It should work great as a radiator.

It will help to contain oil to some extent... after the first vertical section and the first bend from the output all oil that condensates inside will be expelled down the air line anyway. But don't worry it should work fine. You can always build an air/oil separator like I did

Posted: Tue Feb 01, 2011 9:56 pm
by BigBang J
How do you build a air/oil seperator? it needs to withstand 1000psi as well.

Posted: Tue Feb 01, 2011 10:03 pm
by POLAND_SPUD
It is built completelly from iron fittings and a ball valve (for draining)
So if you can find fittings that can handle 1000 psi then you've got a HP oil/air seperator.... personally I wouldn't feel safe using iron fittings at 1000 psi but that is just me


w8 I've got a pic somewhere
nahh for get about it.. there is no point in posting pics that are already here

FOund it! here is my thread >>
http://www.spudfiles.com/forums/how-do- ... 18978.html

ohh and here are a few pics of the filter itself http://www.spudfiles.com/forums/viewtop ... tml#260066

Damn, I know there is no pic of the finished seperator but it basically looks just as depicted on the diagram

Posted: Tue Feb 01, 2011 10:10 pm
by Crna Legija
very nice, but you don't need a check valve at the out put, and you might wanna put a fan in the box to cool it down they get pretty hot.

i have a 1000psi gauge on my but have only taken it to 900psi. that was in the hose that has a 2500psi burst pressure. i got my gauge for free from work, the compressor its self from a junk yard and i had to buy the hose buy got the push to connect fitting free from work aswell.

Posted: Tue Feb 01, 2011 10:26 pm
by BigBang J
Yeah I wasn't to sure, obviously the compressor works fine without a check valve installed since it did not have one in the fridge installed ouside of the compressor. But somebody said to put one on, and it was just lying around so put it on.

I don't plan on running it for very long periods of time, but then I don't really know how hot it will get, so I will monitor it and if it gets to hot I will install a fan or 2.

Ah, I see poland, that is pretty simple for a oil seperator I will have to see about incorporating one in my compressor.

Posted: Wed Feb 02, 2011 1:42 am
by jackssmirkingrevenge
Very nicely done, all it needs is a couple of cooling fans ;)

Posted: Sun Feb 27, 2011 7:49 pm
by BigBang J
NOOOOO!!!

Well guys, my compressor died. I finally got a needle valve and fill nipple fitted to a 20oz. c02 tank, and so I got to filling it with my compressor.
The first try did not make it to 800 psi, so I adjusted my regulator for the compressed air input and tried again, this time I made it to 1000 psi.
I noticed the compressor getting warm after 2 fills in a row so I proceeded to install some fans, the temp of the case was about 110 deg f.
It took about 6 minutes to fill my tank, and so now I was going to fill my tank one last time to get make sure everything was set good, and the pressure halted at about 770 psi and it would not go any higher so I tried adjusting the input pressure a little higher and still nothing. So I turned off the compressor, disconnected my tank and blead the pressure out of the line. I turned it back on and it made a weird gurgling sound, I plugged the output and it would not compress at all.

Do you guys know why it just quit? Was it something I did wrong?

Posted: Sun Feb 27, 2011 7:58 pm
by POLAND_SPUD
hmmm hard to say...
maybe the overcurrent protection thingy shut it down...
if that's the case then w8 15-20 minutes and try to turn it on again
if it's something else then I am afraid that you might have damaged it and you need another one

Posted: Sun Feb 27, 2011 8:29 pm
by BigBang J
No it isn't the over current thingy cause it will turn on and blow air but it wont compress. Maybe this was just a whimpy one and it couldn't hang in there?

Posted: Sun Feb 27, 2011 8:58 pm
by POLAND_SPUD
well then you probably damaged it...
not sure if you can do something with it - I guess not

the good news is that you already have everything for it (tubing, gauge etc.) so in the worst case scenario you only have to replace the compressor

Posted: Sun Feb 27, 2011 9:03 pm
by BigBang J
Yeah, I just need to get another compressor now, disconnect my setup from the dead compressor and reconnect it to the new compressor.
Let me know if you guys come across a compressor that you want to give away:)

Posted: Sun Feb 27, 2011 9:28 pm
by POLAND_SPUD
I know it isn't helping at all and I know how you feel...

but personally I try not to put too much strain on them
sure they are tough when compared with almost anything else but they definitely have their limits

Even if 800-1000psi is possible (never gone that far) it doesn't mean that it is ok for them to reach such pressures

I might sound a bit paranoic but back then when I introduced them 200psi was considered high pressure... anyway this fact is reflected by the title of the original thread '300psi and more' - as 300 psi was a lot back then

Posted: Sun Feb 27, 2011 9:48 pm
by saefroch
I'm personally a big fan of human-powered HPA systems. They don't break down on you like a compressor will.
And they're great for building upper-body strength

Posted: Sun Feb 27, 2011 9:52 pm
by BigBang J
Hmmmm. That is not very encouraging. I was really hoping to get a good 800psi air source from one of these compressors.

Anybody else using these compressors for around 800 psi?
And if this is not my answer for an 800-1000psi air compressor, does anybody have any suggestions for building something that is? Even if it is a hand pump it would be fine.

Thnks guys.