4 Axes Machine Questions

BigJohnT wrote:

The big question is this a stepper machine or servo?

If it is the machine I think it is, it's a bit of both. (step-dir servo)

Rick G wrote:

It seems to me that you might look at the gantry kinematic as a starting point.

Gantrykins appears to allow you to switch axis assignments on-the-fly.
So, to hook W to W, you would use an M100 like
And to slave it to X M101 like:
This is untested. If it doesn't work it can be made to work. (possibly with a tweaked version of trivkins instead)

The machine(s) are old Digital Tool routers, and they are plain steppers. The other machine Andy helped me set up with step/dir servos is only 3 axis.

My main consern about setting up the W slaved, is that I would still need to be able to jog and touch off the Z and W seperately, to set and adjust the depth on the tools. Would I still be able to do this in a configuration with them slaved using gantrykins? I need to go read up on gantrykins I realy haven't looked at it at all yet.

Todd Zuercher wrote:

My main consern about setting up the W slaved, is that I would still need to be able to jog and touch off the Z and W seperately, to set and adjust the depth on the tools. Would I still be able to do this in a configuration with them slaved using gantrykins? I need to go read up on gantrykins I realy haven't looked at it at all yet.

I know that you can jog individually, even when slaved in Gantrykins, by switching to joint mode ($).
You should be able to experiment using the stepper-gantry sample config. (it will work without any steppers attached). Just pretend that X is Z and look at the inputs to stepgens 0 and 5(?) in halmeter or the watch window.

I don't know if you can touch-off in joint mode. I suspect not, as touch-off is an axis thing. I am not sure what the consequences of that are.

I finally got some time to play with some setups and I am not quite sure that gantrykins is going to work. At least not as it is right out of the box. When I switch the command of the 4th axis from slaved to independent I am getting a joint following error. I'd like to look into tweeking the code myself, but I am not sure how to access it. (sorry my newb is showing)

Todd Zuercher wrote:When I switch the command of the 4th axis from slaved to independent I am getting a joint following error. [/quote]

As it is a stepper config it is easy for us to try it out. Can you attach the whole config directory as a Zip file?