Stepper to SerVo motor change-out

Hey all,

I am new on here and have a question regarding changing out my 2006 (year) Vexta (model ASM911AA) stepper motors (DC 2.56V, 2.1A) for new servo motors. I am running a 5x8 table w/ a HSD 4kw ER25 spindle which almost exclusively cuts wood. I have had GREAT luck w/ the steppers but I am itching to increase my CNC output by improving the motors. Any suggestions or recommendations about brands and change-out pit falls?

BTW, I am also getting a new "good enough" 4kw ER25 spindle/VFD ($650 all in) so I can have my HSD 4kw ER25 rebuilt ($1,200). Been considering the Chinese manufacturer Changzhou Hua Jiang Electric Co. who seems to own the Alibaba, AliExpess and Ebay channels in the low-mid tier spindles. Feel free to share any thoughts about spindle/VFD upgrade as well.

https://www.ebay.com/p/Square-4kw-Ai...3327128&chn=ps

Cheers everyone,
'06 Shopbot still running strong!

The DMM servos are nice, I've installed a few of them. DMM | AC SERVO DRIVE | AC SERVO MOTOR | ROTARY ENCODER

Also the ClearPath servos work well, I put a set on a customer machine and just ordered 4 more for the next upgrade on his other machine. https://www.teknic.com/products/clea...-servo-motors/

Either brand will take a step & direction input and close the loop at the drive.

Looks like those Vexta steppers are almost NEMA 34 frame. Mounting hole spacing is a tiny bit off (probably close enough though,) and the pilot boss diameter is much smaller (60mm vs 73mm on a standard NEMA 34.) If their current mount uses the pilot boss as an alignment feature, you'll need an adapter plate. Also looks like it uses a 14mm shaft, which you don't usually see on NEMA frame steppers (common on metric servos though.)
Also, those look to be pretty high performance steppers according to the datasheet. 4Nm holding torque and up to 4000 RPM?
You're looking for higher speeds, precision or both?
What are your max cutting/rapid speeds now?