Depth troubleshooting (way too deep)

1/8" (.1250") 2 FLUTE CARBIDE ENDMILLS - 1600.1250.500

**** Connected to COM4 @ 115200 baud ****

Grbl 1.0c [‘$’ for help]
modified by Larry Mayberry
[‘$H’|‘$X’ to unlock]

$0=10 (step pulse, usec)
$1=255 (step idle delay, msec)
$2=0 (step port invert mask:00000000)
$3=3 (dir port invert mask:00000011)
$4=0 (step enable invert, bool)
$5=0 (limit pins invert, bool)
$6=0 (probe pin invert, bool)
$10=115 (status report mask:01110011)
$11=0.020 (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=1 (homing cycle, bool)
$23=3 (homing dir invert mask:00000011)
$24=25.000 (homing feed, mm/min)
$25=750.000 (homing seek, mm/min)
$26=250 (homing debounce, msec)
$27=1.000 (homing pull-off, mm)
$30=255. (rpm max)
$31=0. (rpm min)
$32=0 (laser mode, bool)
$100=40.000 (x, step/mm)
$101=40.000 (y, step/mm)
$102=188.976 (z, step/mm)
$110=8000.000 (x max rate, mm/min)
$111=8000.000 (y max rate, mm/min)
$112=500.000 (z max rate, mm/min)
$120=500.000 (x accel, mm/sec^2)
$121=500.000 (y accel, mm/sec^2)
$122=50.000 (z accel, mm/sec^2)
$130=790.000 (x max travel, mm)
$131=790.000 (y max travel, mm)
$132=100.000 (z max travel, mm)

I secured the acrylic to a piece of MDF I intended to use as a frame for the project. Good thing, too, so I didn’t go ham on my nice wasteboard. The MDF and acrylic was held down with clamps (no tape) and all seemed flat and level in my pre-cut checks.

I set easel to 0.125 cut depth with 0.02" depth per pass. In watching the machine, it appears to have done nearly all of the 0.125 in the first or second pass, and made some decent progress into the MDF underneath. I ended up smashing the e-stop when there was some chatter and it snapped a small piece of acrylic since it appeared to already be into the MDF anyway.

This is my first attempt doing a full depth cut and acrylic, so assistance troubleshooting would be grand!

I ran this test carve and confirmed with the calipers vs the MDF, and I got the expected 0.02" steps. Not sure where to go from here after reviewing the Z-Axis calibration. Should I simply be expecting some waste from the endmill and set the cut depth more shallow?

Ok, as it turns out, the MDF underneath the acrylic was wildly inaccurate. I tried my cut with 0.49 (after re-measuring 0.51 in some places) figuring I’d sand through. In some places it went right through, in others there was a significant amount of material left.

Is there a way to perform a facing operation so that I can flatten the piece out before beginning a cut in Easel or have I already graduated to Fusion360 ? :smile:

Looks like I need to order one of those dials to check the Z-bits to dial in my Z for full cuts .

I did fumble around in support section of website for a bit, and I did check each ‘depth’ suggestion but none of them applied.