CO2 laser - the learning curve

[raymw]

Yep, a nice steep learning curve, if you're coming in from manual machining. Easy, isn't it. All done by a computer. (insert irony emoji). If the controller does not have an emergency stop position, hopefully  for the limit switches, any one stops all movement (but leaves spindle running - no real need for controller to control spindle - you've got to be left with something to do, instead of just standing admiring it doing its thing), then connect an emergency stop across one of the limit switches (depending if normally closed/open, series/parallel, etc). The emergency stop is necessary in testing, since it seems the controller and software is initially a bit 'random/unpredictable?'

 

A piece of acrylic sheet , even cardboard, will deflect the chips, maybe mounted to a magnetic or heavy base. It could be nice, since it's small, to fold up a steel tray, big enough to contain all the table movement, and enclose it totally - like some of the 3d printers. I'm guessing that the spindle is high speed, low torque, so it will be flinging very small chips (dust) quite some way, as you won't most likely be using flood coolant. If you can stand the noise, then a decent vacuum cleaner will help.

 

wrt making mistakes - you'll learn not to, Already you crashed the spindle - no damage -, but you know what caused it, and thus know how to avoid that. If nothing worrying had happened, you most likely wouldn't bother avoiding the error in future.

To start off, before you are confidant, to test the g-code, then run the machine, with spindle off and well above table, finger hovering over e-stop. I know of folk who've made a spring loaded holder for a pencil, to draw/check the outlines of parts.

 

wrt homing, if you need to, but again, I've never needed to, then get, or make the inverted Renishaw tool setter/probe type device (like at the back of the table in the Haas video I linked to) the patent is well expired, and there are plenty of folk who've made their own, or you can buy for not to much cash from various places. It is still quite legal to use dial indicators, feeler gauges, etc. A couple of cheap digital calipers could be used, with a bit of ingenuity, and would most likely be more accurate than a mechanical switch (even cheaper, the  digital tyre depth gauges - about £4 each.) But, an analogue dial is better, since you can see as it creeps into position, whereas a digital gauge is unreadable while changing. If the gauge is not bolted down solid, then it can be pushed out of the way without damage, if hit too hard.

[raymw]

 

wrt making mistakes - you'll learn not to, Already you crashed the spindle - no damage -, but you know what caused it, and thus know how to avoid that. If nothing worrying had happened, you most likely wouldn't bother avoiding the error in future.

To start off, before you are confidant, to test the g-code, then run the machine, with spindle off and well above table, finger hovering over e-stop. I know of folk who've made a spring loaded holder for a pencil, to draw/check the outlines of parts.

 

Coincidentally, today, this popped up  reference to checklist, dry run through, etc. https://www.youtube.com/watch?v=zMKp-CYTjww