I have wanted a vacuum pump for some time, but I refuse to pay the price for a new one that looks of sufficient strength and duty that I imagine I need.
I have read in different forums about the making of a vacuum pump from a fridge compressor, but with the mixed reviews I was reading I was a hesitant. I am glad I finely did. What a nice unit. I have not used it for any applications yet as I just completed the unit yesterday and have been testing it.
In an attempt to produce more airflow (CFM) I broke this vacuum. I am glad I have started to find these for free. I tried to drill out the discharge to see if I could get more air flow. I have to say don't bother. The line inside is far more restricting and what a pain in the arse to fix, and still have it not work.
The new pump I found is not as good as this one, but should still work for my needs. I will be keeping my eye out for another.
If you are hunting for one look for a compressor with the starting capacitor like this first one. The only real difference between the two compressers I have is that the first had one and the new one does not, and the new one seems to have a hard time starting against the higher pressures.
Step 1: Finding a Fridge Compressor
I found mine out back of a local Motel.
The unit is from a small bar fridge that is common in Motel rooms. Someone else had already removed the coil from the back so I could not scavenge that, but the coil and the coolant was gone.
Note: If the coil is still attached to the fridge there is a good chance that there may still be some pressure on the system, so be careful when cutting lines. There was also talk of oil spilling out of compressor, but mine did not spill oil, even when turned upside down.
I snipped the lines, leaving as much as possible, with a heavy set of side cutters I carry in the truck. The wires were cut as long as possible and the starting capacitor was unstrapped and saved.
What I needed besides was:
A power Switch w/face plate
Cord w/plug (junk TV I had)
Tennis ball ( with a few small scraps of rag)
Soldering torch w/solder
Small pipe cutter
Hot Glue gun