I’m fitting a drag knife to my laser cutter - removing the laser head and putting a knife there instead, actuated with a solenoid for the Z.
It kind of works already with no changes from how I use lightburn for the laser, since I set lightburn to 100% power in line mode - that causes the PWM to be 100% duty cycle, which means the solenoid keeps the knife down.
However, I wonder if I can get slightly better results by configuring either GRBL (on the Ortur board), or configuring lightburn - if the X and Y are held steady for just a moment while the Z (AKA PWM) changes. In other words, when PWM changes, I want no other movement for a few milliseconds.
I tried setting $32 to off (e.g., laser mode off), but then the solenoid stays down all the time even during Moves. I didn’t figure out why yet.
I’d expect there’s something I can do related to “spindle spin up time” but my search-foo across the web didn’t figure it out yet.
Any tips for me for my hack?
This hack might be quick and easy! My other idea is to (ab)use the 3d printer frame for it. The laser frame really is just a (not high torque, but probably enough for thin vinyl and paper cutting) X Y movement system… (and similar for the 3d printer, that’s a generic XYZ system that just happens to have a hotend on; but the bed size is 1/4 the size…)