Hallo Stew,
this is my very first post here and I’m absolutely not used to publish in English, so have a little mercy with my grammar, its rusty. So I will try to use more pictures and reduce my statements…..ha ha ha…..
Some years ago I began experimenting with sewing machine motors for the same purpose than you, it was really not very satisfying. Cheap okay, but a lot of noise and vibrations too (poor bearings), and the little types up to 90 Watt are too weak for the most of that jobs on the lathe, particular for outer grinding operations with wheels obove 1” diameter.
So, if it has to be a little bit nice, really low vibrating, very compact and silent too what’s about using that type of servo motor:

This is a Nanotec DB42 Brushless DC Servo, 48 V, 150 VA, 6000 rpm, and it makes enough power for using 2” to 3” grinding wheels without problems. The only crux is the need of some special servo motor amplifier and a DC power supply. I use the Maxon DEC 50/5 amplifier and a switching power supply 50 V, 6.8 A.

Normally I use the spindle on my Mini_Bonelle tool and cutter grinder…..

but it always does a good job on the lathe too…..

Otherwise, for the limited purpose of internal grinding with small tools this little spindle with an Escap 36 V, 70 VA DC motor is really sufficient.


The system is very compact and can be convenient used on even small machines in the class of 13” between centers. Every normal DC power supply with a max. out put of 36 V and 2 A is sufficient to run this high precision motor.

Bye, Achim from Germany
P.S. more details can by seen on my web site
http://www.metallmodellbau.de , sorry, but only German language there
P.P.S. oops...got some problems with linking the pictures??
P.P.P.S...problems with pictures are solveld...ha ha ha