Tag Archives: 500mw

Robots, with Frickin Lasers – GRBL Settings

While setting up my NEJE 500mw Desktop violet laser engraver, I found there was absolutely no documentation.  It came with a version of grbl on it, but I updated it to the latest Grbl 0.9j.

These settings are working pretty well for me.  I’ve tweaked the dir port invert mask to make the origin (0,0) take place when the gantry is closes to the circuit board.

Grbl 0.9j ['$' for help]
>>> $$
$0=100 (step pulse, usec)
$1=25 (step idle delay, msec)
$2=0 (step port invert mask:00000000)
$3=2 (dir port invert mask:00000010)
$4=0 (step enable invert, bool)
$5=0 (limit pins invert, bool)
$6=0 (probe pin invert, bool)
$10=3 (status report mask:00000011)
$11=0.010 (junction deviation, mm)
$12=0.002 (arc tolerance, mm)
$13=0 (report inches, bool)
$20=0 (soft limits, bool)
$21=0 (hard limits, bool)
$22=0 (homing cycle, bool)
$23=0 (homing dir invert mask:00000000)
$24=250.000 (homing feed, mm/min)
$25=250.000 (homing seek, mm/min)
$26=250 (homing debounce, msec)
$27=10.000 (homing pull-off, mm)
$100=80.000 (x, step/mm)
$101=80.000 (y, step/mm)
$102=80.000 (z, step/mm)
$110=750.000 (x max rate, mm/min)
$111=750.000 (y max rate, mm/min)
$112=500.000 (z max rate, mm/min)
$120=1000.000 (x accel, mm/sec^2)
$121=1000.000 (y accel, mm/sec^2)
$122=10.000 (z accel, mm/sec^2)
$130=175.000 (x max travel, mm)
$131=1200.000 (y max travel, mm)
$132=175.000 (z max travel, mm)
ok

Robots, with Frickin Lasers…

Wow, It’s been far too long since I’ve updated the site.  It’s not that I haven’t been doing stuff, I’ve just been bad at documenting them.

Well, the latest project really deserves a post.  For a while now, I’ve been wanting to do 2 things.  1) be able to make my own PCB’s, and 2) get started in using CNC (Computer Numerically Controlled) machines (robots!).

NEJE 500mW Desktop Violet Laser Engraving Machine Printer

So I find one day searching the interwebs there is a method for making PCB (printed circuit boards) that uses a laser.  The basic process is you take a blank copper pcb, paint it with black paint, use the laser to etch off the paint where you don’t want the copper to be, then use acid to remove the copper.  And then I find this little laser kit online.  Not too expensive, so I take a shot on it.

20150812_143756

Shipping from China it took a little while to get here, but it made it. The parts all seemed to be pretty solid and everything was there.  It was basically just a box of parts, with no instructions, no documentation at all.

Assembly was straightforward though and went quickly.

Gotta say I’ve got no complaints.

20150820_143040Ok, Maybe one complaint.  At some point during the first day, the laser quit being able to shut off during use.  It appears that the SMD mount transistor on the board that controls the laser went bad.  In my attempt to replace it, I managed to screw up the board a bit, but finally just soldered some jumper wires in place and plugged in a replacement transistor I had laying around.  Bada Bing, Bada boom, I’m back in business.  It looks a little goofy, but it works fine now.

20150820_143032Here it is all together. I printed a little grid on the backing board.  Really quite a lot of fun.