ZenXY v2 - Orientation and Endstops and homing

Just finished a Zen XY v2 build. Using an MKS DLC32 board to drive it. It is using grbl 1.1. I bought the full kit from V1 including optical stops.
My question is about homing.

  1. If I’m looking down at the board from the top, should the end stops be on the bottom left or top right? From reading, end stops should be at the end so top right.
  2. In grbl settings, I have $20=0, $21=0, $22=1, $23=3 does that seem correct?
  3. Either way when I home and it gets to the edge, I get a thug thug thug sound like the belt is slipping. Is this because the belt is not tight enough and it “should” stop when it gets to the end? How does it know? Are the motors too strong? Should the machine just stop when it gets to an edge?

If I manually home (Jog to 0,0) then “print” sandify images draw nicely. I would like to queue up multiples or select another one and have it draw the next one without having to manual home once and a while.

Thanks for any help.

The ZenXY hould have homing switches, in which case you can home the machine by starting your sandify image code with G28. This will home the machine, and then it will work fine from there. Or if you know that you’ll have homed the machine first before the “playlist” you can use G0 X0 Y0 at the start of each.

(If you are using GRBL or FluidNC, $H homes the machine instead.)

I use layers to string several elements together with sandify. so all of my code starts with G28 now. When I was using the previous version of the ZenXY, my table would frequently lose the ball homing the X axis, so it used to be:

G0 X0 Y6 F1800
G0 X332 Y6
G0 X0 Y6
G0 X0 Y0 F600

This would home the machine, move the magnet up 6mm from the Y origin, then wipe it back and forth across the table to pick up the ball, which would frequently get lost in homing with Y at zero, becuse I built the table so that the “0” point for Y was actually right on where the center of the magnet was under the table wall. This was a mechanical error in assembly on my part, and I fixed that among other things when I built the beta test Zen V2.

Sandify also has “start code” and “end code” on the export dialog, so you could also end each pattern by deciding the best path to the 0,0 point, if you want it to go to the nearest edge, and then go around the perimeter, you could do that for example.