[jeremyrockjock]

I am building a plasma table and for my x axis I am using two motors, a screw drive and motor on each side of the table. How do I setup Mach 3 to run both motors in sync with each other?

[ger21]

Set up both exactly the same and use Config>Slave Axis.

[jeremyrockjock]

Here are some pictures to help clearify the table configuration.

Two green motors for x axis and the read one for y. I will have another motor for z.

[jeremyrockjock]

I tried that but I think I need to create the 4th axis first. I cannot figure out how. I am using the demo mach3 at the moment while I am still in testing. Is it posible to create the 4th "A" axis on the demo?

[ger21]

Just set it up in Ports and Pins. You also need the motor tuning exactly the same as the X. It should work fine in the demo.

[jeremyrockjock]

Sorry for being so clueless. This is my first build and experience with mach3. I set the pins in pins and port for A axis and X axis the same. I then tuned the motors the same. I then set the hot keys for both axis the same. The motor tuning makes a difference on how the motors run but the hot keys do not change. What am I missing?

[jeremyrockjock]

Am I making this harder than it needs to be? What I mean is am I going to have problems keeping the gantry square? Should I redesign it as a one motor drive belt or chain setup to eliminate constant realignment of he gantry?

[ger21]

Did you set up the slaving? That's all you need to do. If you run the machine within it's capabilities, you shouldn't have a problem.

[jeremyrockjock]

I guess what my main problem is that I cannot get A axis to work at all. The motor will not drive and the coord in mach does not change. How do I activate the 4th axis?

[ger21]

In the Motor Outputs of Ports and Pins, is there a green check under "enabled"? That and setting the pins and port should be all you need to do to get it working.

[scrambled]

Ger21-

I am kinda in the same boat, I have two motors slaved together. X and A axis. All the settings are the same in Mach and in my servo drive (granite devices VSD-e)

The output of each gearbox appears to be different.

Any Ideas? Let me know if I should start a new topic.


Steve

[jeremyrockjock]

I finally got the motors to drive together. However they are not perfectly in sync from one end to the next. I plan to run a timing belt to keep them aligned.

[ger21]

However they are not perfectly in sync from one end to the next.

You're possibly trying to accelerate or move too fast and are losing steps. If you lower the accel and velocity by 50%, will they then stay in sync?

Putting a belt on them will probably make them both lose steps, which isn't much better than being out of sync. Just easier on the machine.

[jeremyrockjock]

I will try that. Thanks Gerry.

[Rhino3Master]

I finally got the motors to drive together. However they are not perfectly in sync from one end to the next. I plan to run a timing belt to keep them aligned.

I had the same problem (1 second delay in the slaved A axis) and I fixed it by changing Config > Motor Tuning > Step Pulse from "0" to "2". Now my motors run perfectly synchronized.

[Tiziano Deodato]

Interesting problem.
I think the only solution is to mechanically/electrically connect the two motors.
By electrically I mean connect the motor coils in series each other (same polarity) and driven by one driver (of course same type of motor).
The electrical sync is required in hight precision.
Width out it at start up or on missing steps the two loose the sync.

[jeremyrockjock]

I will definatly try the step config. I really don't want to tie the motors up with a belt.

I tried running the motors on one driver when I first build it and fried the driver. Luckily they covered it under warranty. But warned me to only run one motor per driver.

I got the torch relay setup last weekend. I did some testing and was thrilled to see it actually cutting.

[ame="http://www.youtube.com/watch?v=j3r1l79moW8"]YouTube - Oct 30, 09 001[/ame]

[jeremyrockjock]

I tried setting the step config. It was already set at 2

[jeremyrockjock]

So I go in a unslave the A axis from Y and calibrate it so it is dialed in to a "t". Same with the Y axis. Then I slave A to the Y axis and A is off (slower by 3 inches over a 40 inch travel). I don't get it. Would the length of the wiring effect the motors?

[ger21]

Try creating a new profile from scratch and see if it works. You could have a corrupted .xml file. You only need to setup the two motors to see if it'll work.