Archive for January 2nd, 2020
Yeah, a Portrait mode plot kinda squinches the annotations into the corners.
Rotating the coordinates to put the X axis along the length of the new platform is, of course, a simple matter of mathematics, but it’s just a whole lot easier to rearrange the hardware to make the answer come out right without fancy reprogramming.
The first step is to affix an MBI-style endstop switch to the left end of the gantry upright:
Shut down the Raspberry Pi and turn off the power!
At the CAMtool V3.3 board:
- Swap the X and Y motor cables
- Move the former Y endstop switch to the X axis input
- Plug the new endstop switch into the Y axis input, routing its cable across the top of the gantry
- Abandon the former X axis switch and its cable in place
Modify the GRBL configuration:
$3=4– +Y home @ gantry left, +X home @ frame front
$130=338– X axis travel along new frame
$131=299– Y axis travel across gantry
Tweak the bCNC config similarly, if that’s what you’re into.
Verify the new home position!
I reset the G54 coordinate system to put XY = 0 at the (new!) center of the platform, redefined G28 as the “park” position at the (new!) home pulloff position, and set G30 as the “tool change” position at the -X -Y (front right) corner of the platform, with bCNC icons to simplify moving to those points.
And then It Just Worked™:
The Spirograph patterns definitely look better in landscape mode:
I eventually turned the whole machine 90° clockwise to align the axes with the monitor, because I couldn’t handle having the X axis move front-to-back on the table and left-to-right on the screen.