Two Stage Comperssors

Hello Men,

I am interested in a very nice two stage compressor. It was built with parts from a variety of sorces. I forget where the 80 gallon tank was purchased but it is an very old one with the cast iron plates fastened to the top that the motor and head are mounted to.

The motor and compressor were purchased from a Montgomery Ward Store many years ago. The motor is a single phase, 25amp, 5HP unit with a 1-1/8" output shaft.

Then my big question is with the two stage head.(also from MontWard)(so says the man); the numbers on the head are as follows and I wonder if anybody knows how to determine the SCFM and PSI from the numbers

one set is -------- H25.8B second set is ------------ 75-6-6515 R

I sure would like to hear from you and determin if I should consider this above mentioned unit or go with the Ingersol Rand that puts out the

15SCFM @ 90psi

Thanks,

Dean Pittsburgh, PA

Reply to
Rettgerinc
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You can expect maybe 14 CFM @ 90 PSI.

"Real old" isn't exactly what you want in compressors. "Brand new" is what you are looking for. Like car engines, they wear out. Tanks rust out, too. Here are a couple of tips:

Look very carefully at the motor control electronics. If there is a mag switch then open it up and examine it for voltage and current ratings. If it it was wired for 440V then it will likely be a small current rating, and if you want to go down to 220V you will have to find a big mag switch which is expensive.

Look very carefully at the compressor head. Is it really dirty? If so, maybe it was slinging oil which collected dirt - in other words, maybe it's worn out.

Look very carefully at the air intake filter. You want to see a nice new one, not a ratty old one or none at all. No air filter for sure means worn valves.

See if you can get the seller to run the thing, then while there is pressure in the tank open the drain valve. What you want to see is just a little oily mist. What you don't want to see is a huge puddle of rusty water.

It's real hard to sell things nowadays. Few sellers have guys leaping at them with cash in hand. Throw money around like a Scotchman with no arms. Think twice before buying, and make the seller really work to make the sale. You are doing a good thing to solicit advice. I once bought an old 2-stage Quincy compressor and put WAY too much money in it. Along the way I learned every lesson I mentioned in this post. Plus one more, and here's that one:

Compressors are top heavy. If you move the thing with a flatbed, really tie it down good. They like to fall over. And when they do, something breaks!

Good luck. The Ingersoll Rand 7.5hp single phase unit is a very nice compressor if you decide to buy new.

Grant Erwin Kirkland, Washington

Rettger> Hello Men,

Reply to
Grant Erwin

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