Identification of old 300s

[Lee's Plumbing]

Im looking for a little help identifying the Ridgid 300 I have that was handed down from my father. I contacted the extremely helpful people on Ridge's tech support line. they informed me that the machine is more than 5 years old, and that they cannot help identify a machine that old. SMH.

Anyway, I was hoping someone can help me identify the RPM's on my machine. I pulled the model # and serial # from the rating tag.
Model # 3158
Serial # 788870.

Im thinking that the machine was manufactured in 1978?

This machine has paid for itself probably 40+ years ago. Crapped out on me 2 months ago . Took it into the repair center in our area- they still haven't gotten around to looking at it.
I have a few gas piping jobs coming up, and think I will be better served buying a new machine. Only problem is, I want to make sure I am buying a machine with the same RPM's I'm guessing that my machine ran at 38 RPM's, but want to make sure.


Thanks

[PLUMBER RICK]

What size pipe is your main concern. Small pipe faster rpm.

Only drawback with slow speed is slower production.

Too fast and you burn the dies and produce power results especially with the lousy pipe we have now.

Rick