[Newbie] Stepper motors

With a driver circuit called a "chopper" the 7.5-degree step can be divided into 12x steps or more. Premium drivers like Gecko do this. Set up with a pulse generator pendant you should be able to get the manual control you're after.

I have played with PWM generators for aligning servos. I wouldn't want to operate a machine on one.
 
My knowledge in this area is weak to non-existent so it's a steep curve for me. Not sure the CNC sub-forum is even the right place...
 
With ACME screws, the stepper locking is of limited use as it doesn't lock out the screw backlash, so you'd need to use the table lock anyway. When driven by cheap, basic controllers they're awful harsh, noisy things too. The more sophisticated controllers do some funky stuff micro stepping and operate steppers far more smoothly and quietly. A geared DC motor like most mill power feeds will probably do the job just as well as you're not looking for positional control.
 
DavidR8 said:
My knowledge in this area is weak to non-existent so it's a steep curve for me. Not sure the CNC sub-forum is even the right place...
Click to expand...

Take a look at how "normal" power feeds are built. They differ from CNC machines for a good reason. They are built to be cheap and provide good speed control. They do not care about position short of turning off if a limit switch is hit.

One feature they do have which you aren't discussing is an electromagnetic or manual clutch. When the power feed is not running, the motor is disconnected from the table. This keeps you from feeling the motor when you want to use the mill as normal. I'd argue that feature is more important than the motor selection.
 
macardoso said:
Take a look at how "normal" power feeds are built. They differ from CNC machines for a good reason. They are built to be cheap and provide good speed control. They do not care about position short of turning off if a limit switch is hit.

One feature they do have which you aren't discussing is an electromagnetic or manual clutch. When the power feed is not running, the motor is disconnected from the table. This keeps you from feeling the motor when you want to use the mill as normal. I'd argue that feature is more important than the motor selection.
Click to expand...

Indeed I hadn’t mentioned a clutch but that is definitely a necessary feature.
I started watching a build by Stefan Gotteswinter which appears to have an interesting clutch arrangement.


Sent from my iPhone using Tapatalk
 
... which Gotteswinter video is that?
 
You must log in or register to reply here.
Back
Top