First "big" lathe

[calblacksmith]

Good morning everyone. It has been a little while since I logged in, i have been too busy and it has been too hot to do much in the shop so other things have taken my time. I was looking in the local Craigs list and came upon this add for a Powermatic  90 for $575.

 

I called him up and went over to take a look. It looked to be in pretty good shape and it ran though a prior owner had done a poor job of converting it to a single phase motor. He had just bolted it to the sheet metal shelf in the L cab and it rattled, shook and made a lot of racket. The lathe came with two face plates, two hand wheels/face plates, two tool rests and a live center. Also in the package was the old 3 phase 1hp motor that was the stock motor for the lathe.

 

We struck a deal for $500 and then disassembled the lathe to load onto my truck. At home, I decided to see if I could get the stock 3 phase motor back in as I do have 3 phase power and it would be a much stronger setup. Thankfully, the man who did the poor conversion, left all the stock wiring in place and he DID label what he disconnected so with a little looking to make sure things were proper, I bolted the motor in place and reconnected all the stock wiring. So far so good. I plugged it in and turned the 3 phase on to the outlet. I checked for power from the machine to electric ground to make sure I would not get zapped if I touched it and all was well. I moved the speed selector from off to the start position and it came to life! Another check from machine to ground showed all was well and a glance at the spindle showed it was in reverse, not forward. I turned it off, unplugged it and switched two phase wires in the plug, connected it all up and as expected the lathe now is operating properly. There is a noise from the outboard side of the spindle and it may be the belt system or the outer bearing going bad but it works smooth other than the slight noise.

 

A second reason that I wanted to run it on 3 phase is that I can get at a reasonable price, an electronic converter/speed control and then I can get any speed from the machine rather than the minimum 1000 rpm on the variable pulley setup. A digital non contact tachometer showed that at the low end, the rpm can go as low as 750, at 1000, it is really 1280 and by the time it gets to 4000 rpm it reads only about 50 rpm high. Now as a result of it running on the stock motor, I have an extra, near new Baldor fan cooled enclosed 1 hp motor to use for something else

 

I had to move things around a bit to setup my turning area but the result I think will be OK. The HF varispeed lathe is to the left and will be used for small things like pens etc while the bigger lathe will be used for bowls and the like. In the pic, it is still on the dollies to move it around and it will be lowered to the ground when the layout is final.

 

The paint is odd though, it is a speckled green/white. It goes behind the maker plate so if it was repainted, the plate was removed when it was painted but it does not seem to have been or the rivets were replaced at the time. By the makers plate serial number the machine was made in 1957 so I am older than the machine by 1 year!

 

I did try to clean up one of the face plates and discovered that the tool rest does not go far enough to the head stock to support my tools, that an as they were made for a small lathe, they are too short to work well on the PM, it looks like new tools are going to need to be made. At one time, two holes were cut in the sheet metal under the ways, it looks like they were there to let a fork lift move the machine. They don't hurt anything but they are not "stock" either

 

I just had to share this with people that would understand. I know it is out of production for a while and that the 12" ability is a bit small by todays standards but I have the ability to make riser blocks should the need come up. I think I got a lot for $500 and I think it is a lot more machine than $500 would buy new!

[Ozwald]

Excellent find!  You most certainly got a lot for your money.  The Delta that I picked up last week, also my first 'big' lathe, has a touch more capacity but that PM is most certainly a better machine all around.  (I got mine for $450)  I love those big older machines.  Thanks for sharing.

[CT Proctor]

I have a PM 45 that's still running good too. I would go through and lube up the Reeves drive and see if that takes care of some of your outboard side noise.

[calblacksmith]

Most of the noise seems to be coming from the spring loaded pulley on the motor, not the headstock. I ordered a digital tachometer yesterday and a 3 phase VSD (variable speed drive) controller will be on the way soon too so I will have full adjustment of the lathe speed with a dial and a readout, like modern lathes.

 

If I can get the speed range out of the motor and VSD, I am seriously thinking about replacing the Vari drive with a constant ratio set of pulleys, a drive I was looking at yesterday will allow the motor to go down to 36 rpm with full torque. At that speed, the cooling fan will not produce enough air movement to keep the motor cool at full power but I suspect I will not be doing a lot of turning at that speed anyway and even then, mostly sanding etc where a lot of torque is not needed.

 

Another thing I have found I need to do is build a false wall behind the lathe. The angled metal under the ways is designed to move most of the shavings to behind the lathe, this is now getting under the equipment that I have there. A false wall will allow me to keep the shavings in one place where a shop vac can get to all of them easily without moving other equipment.

 

I can tell I am going to need to make some longer tools, even my longest tools are uncomfortably short to use on the PM when they were fine on the HF lathe. It never ends huh? LOL!

[woodieboy]

Great find! PM 90 is good machine. It will definitely help you well in turning! Enjoy. Congratulations.