Inspired in the last couple of days by the work of another member here:

(http://www.cnczone.com/forums/vertic..._log_pics.html)

I've decided to dust off the project I had going on way back in 2009 and build something similar myself.

At the time the project got sidelined for one reason or another, but I had built up a good selection of components, including a set of Mitsubishi HC-PQ43 Servos and drivers which I had planned to use.

Looking back at my notes though, I remember not being entirely confident that they were actually a good choice for the project - part of the problem being that I didn't have a full design for the mill at the time so there were lots of variables that could, well, vary!

Having seen Katran's project though, I think that this project would probably represent what I am aiming for and so just before I get started with it again, I wondered if anyone could give me a view on these servos and - all other things being equal an opinion on whether they'd be a reasonable choice (given that I already own them) vs the Keling hybrid 8Nm/ 1000ppr steppers he used.

Obviously I realise that the devil is in the detail, but a 'your wasting your time, sell them and buy something else' vs 'they'd be OK with some setup (pulleys for example to manage torque) would allow me to just tick that one off the list.

Thanks for any help.

The full spec for the HC-PQ43 servo is up here:

http://www.audin.fr/pdf/documentatio...MR-C.doc00.pdf

In summary:

Output : 400W
Torque: 1.27 (rated) 2.92 (max)
Speed: 3000 (rated) 4500 (max)
Pulses: 4000 per revolution