So much food for thought. Thanks for all the replies.
I did test with CAMotics, just didn’t think to mention it. It shows the same estimates as PyCAM.
I don’t feel like I am trying to push the envelope. I set my feeds and speeds based on what Carbide 3D says is appropriate for machining acrylic on the Nomad. I realize the time computations I posted are overly simplistic. The difference between the “perfect case” estimates and the actual time just indicates something isn’t right to me.
I went and played with the machine today. The version of Carbide Motion is 3.0.366, build date 2016-11-01. GRBL version is 0.9g.
I played around with watching Carbide Motion while homing and cutting air. The tool definitely is capable of moving faster than it cuts for me. I was able to observe the velocity jump during rapid homing movements as well as during fast moves while cutting. When it is cutting though, the velocity goes no higher than 200.
Here is the result of $$. It looks like all factory default to me. $110, $111 and $112 would indicate that I should be able to cut faster than 200mm/min. I really expected to find them set at 200.
Test Waiting…
<Idle,MPos:-5.000,-5.000,-5.000,WPos:-5.000,-5.000,-5.000,Buf:0,RX:0,Ln:0,F:0.>
gc_not_motion
___________$$ ___________
$0=10 (step pulse, usec)
$1=255 (step idle delay, msec)
$2=0 (step port invert mask:00000000)
$3=1 (dir port invert mask:00000001)
$4=0 (step enable invert, bool)
$5=0 (limit pins invert, bool)
$6=0 (probe pin invert, bool)
$10=255 (status report mask:11111111)
$11=0.020 (junction deviation, mm)
$12=0.010 (arc tolerance, mm)
$13=0 (report inches, bool)
$14=1 (auto start, bool)
$20=0 (soft limits, bool)
$21=1 (hard limits, bool)
$22=1 (homing cycle, bool)
$23=0 (homing dir invert mask:00000000)
$24=100.000 (homing feed, mm/min)
$25=1000.000 (homing seek, mm/min)
$26=25 (homing debounce, msec)
$27=5.000 (homing pull-off, mm)
$100=200.000 (x, step/mm)
$101=200.000 (y, step/mm)
$102=200.000 (z, step/mm)
$110=2600.000 (x max rate, mm/min)
$111=2600.000 (y max rate, mm/min)
$112=1270.000 (z max rate, mm/min)
$120=270.000 (x accel, mm/sec^2)
$121=270.000 (y accel, mm/sec^2)
$122=270.000 (z accel, mm/sec^2)
$130=250.000 (x max travel, mm)
$131=250.000 (y max travel, mm)
$132=100.000 (z max travel, mm)
ok
gc_dwell
___________N0 G4P0.05 ___________
gc_get_offsets
___________$# ___________
[G54:0.000,0.000,0.000]
[G55:0.000,0.000,0.000]
[G56:0.000,0.000,0.000]
[G57:0.000,0.000,0.000]
[G58:553.000,883.000,-112.195]
[G59:-123.420,-107.380,-127.000]
[G28:0.000,0.000,0.000]
[G30:-2.500,-5.000,-5.000]
[G92:0.000,0.000,0.000]
[TLO:0.000]
[PRB:-2.500,-107.380,-75.255:1]
ok
gc_parser_state
___________$G ___________
<Idle,MPos:-5.000,-5.000,-5.000,WPos:-5.000,-5.000,-5.000,Buf:0,RX:0,Ln:0,F:0.>
[G0 G54 G17 G21 G90 G94 M0 M5 M9 T0 F0. S0.]
ok
<Idle,MPos:-5.000,-5.000,-5.000,WPos:-5.000,-5.000,-5.000,Buf:0,RX:0,Ln:0,F:0.>