Electronics Question for DIY CNC Chassis Kit

[blackonblack]

I am looking to buy my first CNC machine here shortly. In an effort to save money and learn more about the machine i'd like to buy a CNC Kit from K2 and then install the electronics myself. I have a few questions regarding CNC electronics and wiring:

1. Does it really matter if you use Unipolar or Bipolar motors? I know motors with more wires gives more wiring flexibility. I plan on buying 8 wire stepper motors from probotix since these seem common. Also, most people seem to be buying 8 wire motors and wiring them in parallel, is this the recommended way to wire them? Best torque to RPM curve but at the cost of increase currant necessary?
2. Are there big differences in the stepper motor drivers? I was comparing Gecko, probotix and kelinginc. Are geckos worth more than double the latter two?
3. Can you use different drivers with different breakout boards or are they designed to work together? For example can I use a probotix breakout board with gecko drivers or keilingic breakout boards with probotix drivers?

[blackonblack]

can anyone steer a newbie in the right direction?

[oneturboneeded]

Ill say i think that gecko rules the roost because of its mid band resonance damping. ( sorry spelling is not my strong point)

[ger21]

1. Does it really matter if you use Unipolar or Bipolar motors?

It's more about the drive than the motors. There are unipolar drives, and bipolar drives. With 8 wire motors, you'll get more torque from a bipolar drive. And if you have the option, bipolar parallel will give more speed. It's also very important that the motors are a good match for the drives, and the machine. A lot of motors are sold to get the most torque from low powered drives. While they'll give you a lot of low speed torque, they're performance at higher speeds is disappointing at best. There's a lot of posts from people asking why they're big, powerful 425-495oz steppers are so slow. They're usually supplied with 24V systems, when in reality they'd need 100V or more to get the most out of them.

Are geckos worth more than double the latter two?

If you can afford them, then get them.


If you can afford a K2, then don't skimp on electronics. Depending on the size, get a Gecko G540 package with motors in the 380 oz range. You won't need a breakout board with it. Just plug it in and go.

www.kelinginc.net
www.cncrouterparts.com