W. P. Davis Lathe

well.... its been about a year since our last conversation on the Davis lathe, hope everyone is well and had a good Christmas.
i insulated and installed pine boards over the concrete wall where the lathe will live and am ready to power it up.
i have decided to use a vfd and 3 phase motor to power the lathe and have a few questions.
should i set the motor on the lathe and run a flat belt directly from motor to lathe pulley or connect the motor to the wall ?
would you involve the counter shaft and step pulley in any of these scenarios ?
a few photos of a similar install would be helpful.
i have done some searching-studying here on vfd installs but the motor and belt to lathe connection is my main concern right now.
i think i may purchase a vfd and motor kit from dealers electric unless someone has a better place to go.
any help and encouragement will be greatly appreciated.
Dan

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I didn't realize this thread was a year old until your last post. What a cool find. How did you address the excess spindle play mentioned at the beginning?

I would keep the countershaft assembly, even with the VFD set up. It allows more flexibility while maintaining motor speed in its maximum torque range.
 
the spindle play was due to the cap screws being loose on the bearing retainers.
dodged a bullet there!
ndnchf said:
What a cool find. How did you address the excess spindle play mentioned at the beginning?
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Dan,
I would most certainly keep the countershaft, you want to go down to low speeds on this pattern of lathe from the last century, I at home have old tpes of machine tools and as one is not on production work, What is the purpose of having a machine that is going at breakneck speed ? In the day and age that nice old machine was built carbide tools and throwaway tips had not been invented, but that did not stop the guys who worked these old machines of that pattern of turning out some pretty spectacular work, you are fortunate to have also obtained with that old girl a nice batch of good basic tooling , I think your lathe is most handsome, An absolute gem , Will the lathes being made today still be around after the time scale of the old Davis.
Enjoy your old Davis and be like me machining work at a lesser speed than todays burst your rear end guys Hey know what? I get there just the same.!
 
Nice old lathe, looks very much like a Star, especially the tailstock. Love those massive bronze/brass spindle bearings!
I would mount the motor TO the lathe and not to the wall though, unless the lathe itself is also mounted to the wall.
Mark S.
 
thanks guys.... so mount drive assembly to the lathe.
i though that the use of a vfd speed control would eliminate the need for a counter shaft, maybe just belt the motor to the large pulley on the spindle ?
i was not planning to run the lathe faster than its rated speed, by the way what would be the top speed at the spindle ?
if any of my thoughts on this are off the mark please correct me as this is my first attempt to re power a lathe.
Dan
 
I believe most line shafts ran at between 250 & 500 RPM. So with an 1725 RPM motor you would still need 4 or 5 to 1 belt reduction driving the countershaft.
 
should i work my way backwards with pulleys from a max. spindle speed of around 500 rpm to a max. shaft speed of 1750 rpm of the motor.
then use the vfd to decrease rpm of the motor to decrease spindle speed ?
and of course the back gears can come into play for even slower speed.
CluelessNewB said:
I believe most line shafts ran at between 250 & 500 RPM. So with an 1725 RPM motor you would still need 4 or 5 to 1 belt reduction driving the countershaft.
Click to expand...
 
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