Powermatic Model 45 & Model 90?

[Steve Mathews]

In another post I asked for some advice on purchasing a Delta 46-541s. As it turns out a Powermatic Model 45 and Powermatic 90 lathes are also available nearby. Any opinions on these two lathes as something to start on? They are obviously much heavier and robust.

[Doug Ladendorf]

Go for the 90 if you can "swing" it. Much more substantial lathe and a very highly regarded workhorse.

Doug

[Roger Chandler]

The 90 is the way to go if you can. I considered a PM 90 that was available several years ago, but decided to purchase a new lathe with Inverter/VS. If the lathe is in good mechanical shape and has all the parts and is priced right, you cannot go wrong.

[Steve Mathews]

Thanks for the above input. No doubt the PM90 is a beast of a machine but from what I understand there are some disadvantages of it to compared to the PM45. This is what my online research has uncovered so far with some commentary.

The PM90 is 200 lbs. heavier than the PM 45. But is that critical, at least to me? I still don't have specific tasks laid out for my use of a lathe.

The inboard spindle is larger but non-standard as far as the availability of accessories are concerned. Seems like that would be a limiting factor.

According to specifications I've read on both machines the PM45 operates at a lower speed, 350 vs 500. Seems the lower speed would be an advantage.

Any additional comments would be appreciated before making a final decision.

Lastly, what would it cost to install a VFD on a 3 phase, 1 hp motor? Would that give me the opportunity to run the lathe at a slower speed? If installed on a mechanical variable speed lathe, what speed should the lever be set at?

[Michael Dye]

My son and I both have PM90's. We acquired ours at a school auction in Las Vegas maybe 20 years ago, before my son was even born. He is now 18 and a master turner, at least in my mind. All due to being brought up on the 90. It is a heavy machine but for turning large, raw edge blanks, you need the additional weight. Honestly, I have never used one of the newer electronic lathes so have nothing to compare with. But that being said, if you can find a decent PM90, you will enjoy the years of service it gives you. The only negative would be the 1 1/8" tool rest which can be a pain. But the headstock is 1 1/8" (easy to find faceplates and Novachuck bits) and I make my own toolrests so it's not such a big deal. Good luck

[Michael Dye]

Sorry, I didn't proof the text before I hit "enter". The headstock thread is actually 1 1/2" not 1 1/8". 8 tpi, I think.

[M Toupin]

The PM90 has a 1 1/2 X 8tpi spindle but I would not call it non-standard. Every chuck manufacturer sells either a 1 1/2X8 chuck or an adapter.

A VFD is a nice addition and will give you variable speed. Keep the reeves drive as it will allow you to fine tune your speed while keeping the torque up. Think of it like a transmission in your car, slow speed and high torque (like 1st gear) and high speed low torque (like 4th gear). Spend a few extra $$ and go with a sensorless vector drive which has some low speed torque compensation as apposed to the simple volts/hrz drives like the FM50.

http://www.vintagemachinery.org/photoindex/detail.aspx?id=13825

Mike

[Doug Ladendorf]

No doubt the PM90 is a beast of a machine but from what I understand there are some disadvantages of it to compared to the PM45. This is what my online research has uncovered so far with some commentary.

Goodness no. I don't know where you have been doing research but take a look at the PM 90 threads on OWWM.org. Three phase with VFD is pretty ideal. You have both the reeves drive AND the VFD to adjust speed. The thread is easily found in accessories since the 90 was so popular. You can also add riser blocks to provide greater swing if you desire in the future. The additional weight is exactly what you want to help reduce vibration. Absolutely no question over the 45.

[Steve Mathews]

I'm beginning to understand the benefits of a heavier lathe. The top of the line current model from Powermatic is apparently more than 300 lbs heavier than the PM90. There were only a couple of posts on other forums preferring the PM45 over the PM90 because of the smaller spindle. Thanks for setting me straight on that issue. As long as the selection of accessories is not a problem I'll lean toward getting the PM90. So, one with a 3-phase motor would be better because of being able to fit it with a VFD? The one I was considering has a single phase motor.

[Mark Greenbaum]

A fellow at work is the process of acquiring all US made Powermatics for his shop. Most from auction site (govdeals.com), and most have 3 phase motors. He purchased a VFD capable of running up 5 hp for about $200, and can if he wants do variable speeds. He's an electrical engineer, so wiring and controls are not a problem for him.