Hi folks,
I recently got to the point of being able to try my first crown plot (plot against the crown?). While it was very exciting to see the MPCNC doing its thing, the image printed much too large.
The first thing I looked at was calibrating manual jogging in Repetier Host-Mac.
It was going twice too far (20mm when the 10 button was pressed), so in Arduino, I modified configuration.h as follows:
/* #define DEFAULT_AXIS_STEPS_PER_UNIT { 200, 200, 4535.44, 200 } //MPCNC */
#define DEFAULT_AXIS_STEPS_PER_UNIT { 400, 400, 4535.44, 200 } //GBN
That corrected manual jogging (or at least close).
However, the default crown gcode still was very large.
So I created a very simple square svg and converted it to gcode at jscut.org (I used settings cribbed from the v1 “Estlcam basics” page):
G21 ; Set units to mm
G90 ; Absolute positioning
G1 Z2.54 F2100 ; Move to clearance level
;
; Operation: 0
; Name:
; Type: Engrave
; Paths: 1
; Direction: Conventional
; Cut Depth: 3.175
; Pass Depth: 3.175
; Plunge rate: 127
; Cut rate: 900
;
; Path 0
; Rapid to initial position
G1 X10.0002 Y20.0002 F2100
G1 Z0.0000
; plunge
G1 Z-3.1750 F127
; cut
G1 X9.9804 Y20.0000 F900
G1 X0.0003 Y20.0000
G1 X0.0003 Y10.0198
G1 X0.0000 Y10.0000
G1 X0.0003 Y9.9802
G1 X0.0003 Y0.0003
G1 X9.9786 Y0.0003
G1 X10.0002 Y-0.0000
G1 X10.0218 Y0.0003
G1 X20.0000 Y0.0003
G1 X20.0000 Y9.9784
G1 X20.0002 Y10.0000
G1 X20.0000 Y10.0216
G1 X20.0000 Y20.0000
G1 X10.0200 Y20.0000
G1 X10.0002 Y20.0002
G1 X10.0002 Y20.0002
; Retract
G1 Z2.5400 F2100
M2
On my MPCNC, this plots a square 160 mm on a side instead of 20 mm.
Any suggestions where else I might look?
Thanks!
Greg
Some additional context:
Using MPCNC813_GLCD firmware flashed to an older Mega2560/RAMPS1.4/driver combination.
Steppers are Nema 17 from v1
No end stops
Mac OS 10.13.3
Details of what repetier reports at connection;
3:29:23 PM: Connection opened
< 3:29:24 PM: start
< 3:29:24 PM: echo:Marlin 1.1.0-1
< 3:29:24 PM: echo: Last Updated: 2017-05-04 12:00 | Author: (none, default config)
< 3:29:24 PM: Compiled: Feb 27 2018
< 3:29:24 PM: echo: Free Memory: 3553 PlannerBufferBytes: 1232
< 3:29:24 PM: echo:EEPROM version mismatch (EEPROM=? Marlin=V37)
< 3:29:24 PM: echo:Hardcoded Default Settings Loaded
< 3:29:24 PM: echo: G21 ; Units in mm
< 3:29:24 PM: echo: M149 C ; Units in Celsius
< 3:29:24 PM: echo:Filament settings: Disabled
< 3:29:24 PM: echo: M200 D3.00
< 3:29:24 PM: echo: M200 D0
< 3:29:24 PM: echo:Steps per unit:
< 3:29:24 PM: echo: M92 X400.00 Y400.00 Z4535.44 E200.00
< 3:29:24 PM: echo:Maximum feedrates (units/s):
< 3:29:24 PM: echo: M203 X190.00 Y190.00 Z8.40 E25.00
< 3:29:24 PM: echo:Maximum Acceleration (units/s2):
< 3:29:24 PM: echo: M201 X500 Y500 Z35 E10000
< 3:29:24 PM: echo:Acceleration (units/s2): P<print_accel> R<retract_accel> T<travel_accel>
< 3:29:24 PM: echo: M204 P400.00 R3000.00 T400.00
< 3:29:24 PM: echo:Advanced: S<min_feedrate> T<min_travel_feedrate> B<min_segment_time_ms> X<max_xy_jerk> Z<max_z_jerk> E<max_e_jerk>
< 3:29:24 PM: echo: M205 S0.00 T0.00 B20000 X4.00 Y4.00 Z0.20 E5.00
< 3:29:24 PM: echo:Home offset:
< 3:29:24 PM: echo: M206 X0.00 Y0.00 Z0.00
< 3:29:24 PM: echo:Material heatup parameters:
< 3:29:24 PM: echo: M145 S0 H196 B62 F0
< 3:29:24 PM: M145 S1 H240 B110 F0
< 3:29:24 PM: echo:PID settings:
< 3:29:24 PM: echo: M301 P17.98 I0.98 D83.62
< 3:29:29 PM: echo:SD init fail
< 3:29:29 PM: FIRMWARE_NAME:Marlin 1.1.0-1 (Github) SOURCE_CODE_URL:https://github.com/MarlinFirmware/Marlin PROTOCOL_VERSION:1.0 MACHINE_TYPE:MPCNC EXTRUDER_COUNT:1 UUID:cede2a2f-41a2-4748-9b12-c55c62f367ff
< 3:29:30 PM: echo:DEBUG:INFO,ERRORS