208OZ.IN stepper motor

[whensparksfly]

so do you think theses motors will work or do i need bigger ones

[Robin Hewitt]

Quite possibly the motor is fine and dandy. Fitting a larger motor might be better, could make things worse. You can either have a wild guess or you can do the maths. The wild guess is standard practice but I cannot say I would recommend it.

Let me pinch a stepper power graph at random from Gary's ZAPP Automation website. Gary is helpful because he gives you graphs. It is unwise to assume the motor holding torque number tells you much about what the motor will actually do. Gary has the right idea.

Notice how by 300 rpm the torque has fallen by about half and is just about to plummet should you dare to go any faster.

(HLAF should read HALF, meaning 400 steps per rev)

You don't actually require much torque for a plasma cutter because you aren't pushing against the tool. OTOH, should you find yourself at the wrong end of that 4 foot table with this motor fitted, you might have enough time to make a cup of tea before it was ready to start cutting.

Can you find a graph for your motor? Only then can you start to decide how to gear it. It is always a compromise between step accuracy and rapid movement. There will also be a maximum speed where you can slam the gantry in to reverse without losing position, it is very useful if that is near your proposed cutting rate.