diy compressor



Im sorry i know alot of posts have been made about this, and i read all the way through Fez's post. it was sorta helpful, but i was wondering if my diagram looked about right? i had thought about buying a compressor but at 300 dollers i had to ask myself why when i could make one.

the only thing stumping me is the placement of the auto shutoff switch and power, also what to use for the auto shutoff switch.

mind you when built it would be much more compact but i find exploded views make things easier to understand


I would forget the moisture trap between the compressor and tank, that is the reason for the tank, it is called a separator in technical terms, so it separates out water and oil.

As for a pressure switch, the one you get should have multiple outlets, and have provisions for a safety release, and hopefully an unloader valve. A check valve should be inline from the compressor output to the tank, downstream of the unloader hook up, this way when it shuts off, the check is closed by tank pressure, and as the unloader circuit opens, it relieves all pressure eon the compressor, making starting much easier.

Your power wires for the compressor will tie into the pressure switch, as well as the cord coming in, thus breaking the circuit as pressure is achieved. I used a Porter Cable donor. This is the easiest way. Then all the switches, check valves, wiring and such are there. You just have to hook the power wires for the fridge compressor to the pressure switch and hook the discharge line to the tank inlet.

Think I posted it before but this site,DIY Silent Compressor, was the directions I followed. It even gives part numbers for items if you are purchasing everything from scratch.

If you need it I can take pics of my unit so you can see how I hooked everything up. Just let me know.
Eventually it would be nice to have a sticky post on how to build a silent compressor with a fridge motor. It could have diagrams and parts list, warnings, explanations, videos and useful links (to more information or online stores) :)
yeah i was hoping that my diagram was right but nope im still missing parts
The power to the motor goes through a pressure switch that's on the outlet of the tank before the regulator. It is that that controls the power when the pressure reaches the minimum or maximum.
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So after that last diagram wmle posted this is what i came up with, im hoping its right

i reviewed all the comments in this thread, and as far as i can tell this is correct with the exception that the fittings to make it airbrush size are missing

Ok, instead of a separator between the compressor and the tank you want a check valve. This will keep air from coming back on to the compressor. Going to your pressure switch you do not need one. In between the check and the compressor should also be a "t" fitting allowing a line to connect to the unloader which should be in your pressure switch, this is how the air bleeds off the pressure side of the compressor before start up. If i think of it ill make up a diagram.

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Here is a modified diagram.


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thanks Wmle im trying to do the community a bit of a service as i try to save up the money and bookmark all the parts i need. So at least now as a community we have a diagram to run off of