Powermatic 45 vs. Rockwell 46-450

[Dan Cobian]

Second posting on this site and the the last one helped me quite a bit, looking for a repeat performance. Looking at 2 lathes that are local. Both are 240v 3 Phase 1 HP.

The powermatic 45 is selling for $450 and the Rockler 46-450 is up for auction starting at $300.

I plan on turning mainly bowls and I know (after my last post) that I will have to spend another $120 on a frequency converter.

Any thoughts?

[Bob Hallowell]

Both are a great price but the delta going down to 320rpm is great plus it is only $300. It would be my choice.

Bob

[Bernie Weishapl]

Rockwell would be my choice. Would make a great lathe with the VFD on it.

[Bob Bergstrom]

I've been turning on my 450 for 15 years. Only thing I've replaced is the bearings. The lowest speed is 340. This is the outboard table I built to turn up to 24". Both lathes are tanks. See it here http://i306.photobucket.com/albums/nn274/bbergst/IMG_0302.jpg

[Bill Bolen]

I turned on both of these lathes a number of years ago and both are real tanks. I think I lean towards the Delta with the lower speed though. My big question to you is, is the swing big enough since you mainly want to turn bowls? You will find you will want to try bigger and bigger and unless you can turn outboard on one of these you will be limited...Bill...

[Wilbur Pan]

What's the swing over the bed on these lathes? Having had a gap bed lathe in the past, I can say that the gap isn't going to be really useful for anything besides platters if you are using a modern day chuck. So if you are looking at turning bowls, I'd go with whichever lathe gives you the bigger swing over the bed.

Also, if you are getting a frequency converter, presumably to allow you to run a 3 phase motor off of your single phase shop electrical, you might want to consider getting a variable frequency drive, which would give you variable speed as well as the 3 phase --> single phase conversion.

[Dan Cobian]

Thanks again to everyone for your help and interest. I am stepping up from a Jet mini, I do feel that this will tide me over for a while. Also, my logic is that I will be able to resell this at some point in the future at a profit when/if I outgrow the 46-450. Bob Hallowell recommended the FM50-101-C from “factorymation” which should get me both a step-down in voltage and an adjustability that wasn’t there before. The swing over bed is 12” on both lathes I'm looking at I believe. The Powermatic shows 16" swing over gap bed (which is 4 1/2" in width).

Still looking into how hard it would be to turn outboard on these. I saw an interesting post (with pix) from Bob Bergstrom in this thread that looks like a reasonable option for "outboard turning". I hope to pick his brain if I can get the lathe. Surpisingly, everyone has recommended the Rockwell vs. the Powermatic. I thought that Powermatic had a bigger following.

[Dan Cobian]

From the looks of these pix, I believe I can turn outboard?

[Bob Hallowell]

My 80's delta that I show'ed a pic of in your other thead has the same outboard thread and locking ring as yours does, you can get faceplates and chucks to turn outboard prolly 1x8 lh. You can mount a toolrest many ways form buying an aftermarket rest that stands on the floor like the powermatic to mounting a pipe and a big hinge like Keith Burns did ( you can do a search) and maybe even come up with a bed extension and a bigger banjo and mount it to the outboard side somehow like a oneway.

I said the delta beacuse of the lower speed means more turque when you use your vfd cause you don't have to go as low in hz and the outboard threads for turning bigger and also easy vacuum chucking

Bob

[Jim Underwood]

This is the image Bob was trying to post:
http://i306.photobucket.com/albums/nn274/bbergst/IMG_0302.jpg

[Bob Hallowell]

Jim,
That is what I had invisioned, my 80's delta came with something like that.

Bob

[Bob Bergstrom]

Thanks Jim, Will figure it out eventually

Dan,
Turning outboard isn't really any harder than cutting to the left rather than the right. My outboard banjo is quite stout, (make from one inch plate) but I saw one on the internet that used two squared 1" dowels with a spacer welded in between make the a slot. I only use the tail stock to reverse turn the bottom. The oneway 1x8 threaded chuck can go both inboard and outboard. I have acquired a 1 1/2 hp. 3 phase motor and if someone could advise me on which variable speed to use (variable toque or constant toque I would appreciate it.

[Mike Spanbauer]

Constant was the recommendation to me when I was investigating VFD's for my PM90 (1hp 3ph).

It'll offer better "oomph" at all speeds when you reduce the frequency for slower speeds.

mike