Lathe Upgrade

[William C Rogers]

A while back I posted a question on how important larger than a 12" swing for a lathe was and should I consider buying a new lathe. That being a Grizzly G0766. In summary most of the comments were my PM 90 was a proven and quality lathe and if I wanted to turn larger than 12" I should look at either outboard turning or raising the lathe. I appreciate all the comments as they were helpful. There were a lot of pros for the Grizzly, but there were also cons. Evaluating everything I decided to raise my PM 90 up 3", giving me a 18" swing. Using hard maple and acrylic for the tailstock and headstock I followed Roy Turbett guideline posted on the OWWM site. The cost to raise the lathe was minimal, new belt, some acrylic, and steel around $150. However I bought 5 new Robust tool rest made specificly for me that were a bit more. Not unhappy at all as I really like the rest and Robust was great dealing with. I would have need some tool rest even if I went with the Grizzly. The last thing was my motor and speed consideration. I have a 1 hp single phase motor and my low speed is 330 rpm. I put a 15" (largest I had) chain saw rounded blank in the lathe. I had added 200lbs of sand before. The lathe rocked with the unbalance but did not walk and I was able to round it up with little problem. I haven't stalled the motor. For now I am going to stay with my single phase motor, but I I get larger blanks may reconsider go a 3 phase with VFD if I have speed/power problems. I don't have all the features of a new lathe, but I am happy with the end result. I can always add the 3 phase and get some of the same features, but more parts less reliability.


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[Doug Ladendorf]

Hey, that looks great! Very nicely done. Glad it's working out for you. I think you just increased your lathe's resale value more than the cost of materials!

Doug

[Roger Chandler]

Nothing wrong with upgrading "old iron!" Nicely done William. I had an opportunity several years ago to get either a PM-90, or a PM-45, but decided to go new. My understanding of lathes back then was not near what it is today, so that was the best move for me.

[William C Rogers]

I'm not in the selling mode right now. I bought this lathe 7 years ago for $180 and added the single phase motor for $75. At the time I was just turning pens and small boxes on a midi. Didn't even think about bowls at that time. The Grizzly seems to be a great lathe for the value and if I didn't have the PM 90 the cons would not have prevented me from buying the Grizzly. The PM 90 is somewhat bullet proof and for now it will do everything I need as a hobbist. With the money saved I bought some Thompson scrapers and gouges. I really like the Robust tool rest.

[Glenn C Roberts]

Bill, Is that a new window behind the lathe? (!!!)

[William C Rogers]

The shop is about two years old. Someday I will get around to taking the stickers off the windows. So no, it is not new from throwing something out of the lathe. Possible, but not too worried, always wear full face shield.

[William C Rogers]

I thought I would post some of the differences I did raising my lathe from the guideline Roy provided. I used hard maple instead of particle board with Formica. I used 1/2" acrylic for for my tail stock to slide on the ways. This was from a 100% acrylic cutting board sold by Menards. It can be cut and sanded. I glued it to the maple using contact cement. I made a "box" to help keep it place for gluing. It is also bolted to the tail stock.
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I cut dados a 1/4" in the top and bottom with the same setup. The head stock and tail stock are slightly different in width, I did the tail stock and then head stock. I installed a piece of cold roll steel 2 1/2" wide 1/2" thick in the bottom to run in the ways. I also used the 2 1/2" steel in the head stock. After everything was assembled I checked alignment of the centers and I needed to put a 0.004" shim in the tail stock to get a satisfactory alignment.
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One be thing I did that I hadn't seen before was modify my belt cover. I have seen where some have made them out of wood. Powermatic made some from plastic, thinking this would be easy to extend, I bought one and extended it. It "looked" ok, but the plastic is so thin (about 1/16") any pressure attaching, it would fail. So I thought I might as well try to extend the cast iron cover. it took me about a hour to cut the cover into two pieces using a 3" cutoff wheel. Kind of a pain. I then took some 1/4" steel and bent it to fit the contour cf the bottom. I tapped 1/4" -20 threads in the casting. I bolted the straps to the bottom with the bolt heads inside and put it on the lathe and bolted the top half to lathe as you would install it, then drilled to bolt the top half to the steel straps. There was plenty of clearance inside.
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I glued some plexiglass for backing and then bondo and grind off the screw protrusions.
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A little paint and done. Now this "feels" like a Powermatic belt cover.
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I added 250 lbs of sand to the lathe, 100 lbs on the shelf, 100 lbs hung from the bed in wood box, and 50 lbs in the bottom of the cabinet.
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Note that hat I have the offset tool rest extension shown in the last picture. This will allow me to make full use of the swing.