Mostly 3d printable cnc 3D for print

Designer

Saul Mendoza

3d model description

Just another mostly 3d printable CNC/engraving mill
Documentation in progress...

* How to assemble

* How to Print

  - Many objects are n...ot in print orientation

  - All needed print support already included on all objects

* What works

* What doesn't work

  - V4 GRBL board came with step and direction flipped on all axis, had to make changes in grbl pin out and recompile. Added grbl hex file I used.

  -- Microstepping also does not work on V4 GRBL board (tied to ground)

  - ESC overheats trying to power RPI

* How to configure Arduino, GRBL, RPI

  - test Brushless motor

  -- http://abyz.co.uk/rpi/pigpio/download.html

  -- Download PWM program

  -- #wget abyz.co.uk/rpi/pigpio/pigpio.zip

  -- unzip pigpio.zip

  -- #cd PIGPIO

  -- #make

  -- #sudo make install

  -- Connect ESC control to BCM pin 17 (physical pin 11)

  -- To start the pigpio daemon

  -- #sudo pigpiod

  -- to run PWM signal on pin 17

  -- #pigs s 17 500 - initializ

  -- #pigs s 17 1065 - moves slowly

  -- To stop the pigpio daemon

  -- #sudo killall pigpiod



  - Current GRBL Values

  -- Using Quarter Step !!removed jumpers & connected VDD to MS2!!

  -- set Vref = 250mV (used 100mV when full steepping because vibration)

  -- Still need to set soft limits

  -- $0=5 (step pulse, usec)

  -- $1=1 (step idle delay, msec)

  -- $2=0 (step port invert mask:00000000)

  -- $3=0 (dir port invert mask:00000000)

  -- $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=1 (hard limits, bool)

  -- $22=1 (homing cycle, bool)

  -- $23=3 (homing dir invert mask:00000011)

  -- $24=50.000 (homing feed, mm/min)

  -- $25=800.000 (homing seek, mm/min)

  -- $26=250 (homing debounce, msec)

  -- $27=1.000 (homing pull-off, mm)

  -- $100=200.000 (x, step/mm)

  -- $101=200.000 (y, step/mm)

  -- $102=200.000 (z, step/mm)

  -- $110=800.000 (x max rate, mm/min)

  -- $111=800.000 (y max rate, mm/min)

  -- $112=800.000 (z max rate, mm/min)

  -- $120=10.000 (x accel, mm/sec^2)

  -- $121=10.000 (y accel, mm/sec^2)

  -- $122=10.000 (z accel, mm/sec^2)

  -- $130=200.000 (x max travel, mm)

  -- $131=200.000 (y max travel, mm)

  -- $132=200.000 (z max travel, mm)



  - Testing OLED

  -- Enable i2c

  -- sudo apt-get install git

  -- git clone https://github.com/adafruit/Adafruit_Python_SSD1306.git

  -- cd Adafruit_Python_SSD1306

  -- sudo python setup.py install

  -- Run Adafruit Examples

  -- Possible Dependencies

  --- sudo apt-get install build-essential python-dev python-pip python-imaging python-smbus



* Software / Workflow

  - Fritzing, create circuits and export to SVG

  -- http://fritzing.org/home

  - Inkscape, get PCB trace outline (check out example file)

  -- https://inkscape.org/en

  -- load SVG file exported from Fritzing

  -- change view to outline (view → display mode → outline)

  -- ungroup objects (object → ungroup)

  -- create a copy of all objects you would like to outline

  -- new copy combine all paths/objects (path → combine)

  -- go to fill settings (ctrl + shift + F)

  --- change fill to no (X)

  --- change stoke to flat color

  --- Note: can make outline bigger by playing with “stroke style”

  -- create outline (path → stroke to path)

  -- save new SVG

  - BlenderCAM, create G-Code from inscape SVG File

  -- http://blendercam.blogspot.com/p/download-and-installation.html

  -- will have to do some postprocessing here to remove what you dont want/need

  -- i'll try and and more info here later

  - Universal G-Code Sender, send G-Code from RPI to arduino

  -- https://github.com/winder/Universal-G-Code-Sender

  -- OR bCNC

  --- https://github.com/vlachoudis/bCNC/wiki Read more

3d model print parameters

* Tested circuit using Attiny85 and 3mm IR LED emitter and receiver
* GPIO assignments (BCM)
power =21 #shutdown button
center=20
up =26
down... =13
left =16
right =19
rpmPin = 6 #input pin to sense RPM
escPin = 12 #output to the ESC
#read PWM value = 15 (/dev/ttyAMA0)

* Test script before adding it to startup
* unzip script in your documents folder
/home/pi/Documents/mlmCnc/main.py

* Add following to rc.local (sudo vi /etc/rc.local)
sudo pigpiod
sudo /home/pi/Documents/mlmCnc/main.py &

*Make sure serial port TTYAMA0 is available
*Make sure pigpio libraries are installed Read more

Tags

Cnc Engraving Grbl Diy Arduino Mill Raspberry pi Plotter Pcb Mantis

License

CC Atribution