[Rees Guitars]

I have a new 2'x2' router nearly built, budget is tight and I don't really feel like getting into changing up my 3 axis drive unit right now.

Does anyone see a problem with using a timing belt and pulleys across the back shafts of the two X steppers? One stepper would be live, the other would just be spun by the belt. Planning to only use it for light duty PCB milling and engraving work, for the time being.

[JerryBurks]

I believe a single stepper with belt is not unusual, but often centered so that both screws are driven by the belt. Maybe the reasoning is that both screws are then affected the same by belt flex. But in any case this is much better than a single screw and centered drive on a crossmember.

[wizard]

Obviously this is less than ideal. I would suggest removing the motor to eliminate cogging, steppers aren't exactly smooth free spinning devices with the strong magnets In place.

However do realize that if you have a step and direction machine you could just add another drive. You would need to run step and direction to both drives. If the motor is there already then it probably is in the same ball park as new belts and pulleys.

I have a new 2'x2' router nearly built, budget is tight and I don't really feel like getting into changing up my 3 axis drive unit right now.

Does anyone see a problem with using a timing belt and pulleys across the back shafts of the two X steppers?

I don't like the idea of driving the slave stepper around. You would also be better off centering the motor between the two lead screws. One foot to either screw isn't too bad. Use a fairly hefty belt and keep it taught. An idler on the long side will likely help too.

One stepper would be live, the other would just be spun by the belt. Planning to only use it for light duty PCB milling and engraving work, for the time being.

Both of these are precision uses as such you will need to pay attention to the belt fit up. Make sure you have plenty of wrap around each pulley.

I have to wonder why the motor is already there. All things considered it would probably be easier to get the alternate motor running.

[Rees Guitars]

Ehh, you're right. I already have the pulleys, so figured it would only be around $10 for the belt, but I just bit the bullet and ordered another Gecko driver. Gonna do it the right way.

Thanks!

[JerryBurks]

When you set it up, keep in mind to get both steppers to cooperate in lock step. That means turning them on to hold in the same step position before you tension the belt and tighten the pulley screws. Otherwise it becomes a crap shot and you may end up with steppers working against each other and having less power than with a single stepper.