[Yellowbeard]

Does anyone know where I can find a controller for 3 axises, XYZ with two synchronized stepper motors, (Y axis)? One which will control 1200 in/oz motors. I am building a cnc machine for cutting, shaping and polishing granite countertop. I've modified a Bridgeport milling head so that I can obtain spindle speeds necessary for cutting as well as speeds for polishing. I'm using 1" ballscrews and Hydwin slides to move axises. I'm planning to use 4 of the following motors:


Holding torque-Nm (oz/in) +/- 10% 8.7 (1208)
Rated voltage 2.7
Rated current per phase (amps DC) 6.0
Resistance (Ohms) +/- 10% .45
Induction (mH) +/- 20% typical 5.1
Motor length (mm) 118
Rotor inertia (g-cm^2) 2700
Weight (kg) 3.8


The motors will be belt driven and geared 2:1. Two motors will drive the gantry (X axis, with Z axis), (Z axis approx 200 lbs, X axis total approx 500 lbs) down the Y axis. This should be enough to drive the gantry. I need these motors to be synchronzied. I'm also looking for the right power supply and parrallel interface card. I'm planning on using Gecko drives for the motors, but I need to find the board / interface card which connects the motors to the PC.

[turmite]

yellowbeard Mach2 will do slaving, which is what I think you are talking about. Using one of those motors on each end of you Y axis? Right? If that is the case Mach2/3 will work just fine and is only $150 US with free upgrades. Support is first class. I would also make the suggestion you contact Mariss at Gecko about drives for those motors and I would do that before I actually bought the motors if you don't have them yet! The guy is a stepper motor genius!

Mike

[JRoque]

Good advice Mike. Yellowbeard, this might also work: get a single axis drive and connect it to the existing Y drive input. Drive inputs are usually high impedance allowing you to connect both of them to the same Y output of your PC. Both drives should have similar specs.

BTW, I've heard that sync'ing two open loop motors tend to cause problems. It seems most folks go for mechanical synchronization. A timing belt between the two Y screws is one idea.

JR