CNC Machine
[Equipment|Back to list of Equipment]]
|
|
General
|
 |
READ ALL OF THIS PAGE PRIOR TO TRYING THE CNC MACHINE
THE CNC MACHINE HAS THE POTENTIAL TO HURT YOU
OR DESTROY ITSELF - IT DOES NOT CARE!!!
HARDWARE
The machine is located in the basement of LVL1. It is a homemade Solsylva CNC machine built by Brian Wagner during 2008/2009. The plans were purchased online. These plans are FANTASTIC. If you are thinking about building a CNC machine use these plans! Here is the link to the plans I built. http://solsylva.com/cnc/25x37dual_leadscrew.shtml David Steele - the maker of the plans - has new plans. I would recommend building his newer machines. Spend some time on his website: http://solsylva.com/cnc/cnc_plans_home.shtml The plan book that I used is in the plastic bin near the CNC machine. Feel free to look through it, but do not remove it from the space!
The electronics that are used for the CNC come from Probotics. http://www.probotix.com/ Specifically http://www.probotix.com/index.php?view=product&product_id=14 I purchased a kit something like this http://www.probotix.com/3_axis_stepper_motor_driver_kits/3_axis_sidestep_stepper_motor_driver_kit/ with a parallel port isolation board, 3 drivers and a power supply. I recommend this company highly for stepper drivers. The drivers use Allegra stepper chips.
The steppers are connected to an old Sony Vaio laptop that runs EMC2 / Axis on Ubuntu. You have to have a computer with a parallel port to run the CNC. Parallel ports are getting harder and harder to come by!
SOFTWARE
Design Software
Inkscape http://inkscape.org/ - create vector images to import into Cut2d
Eagle http://www.cadsoftusa.com/ - create PCB's that can be milled. You will also need pcb-gcode - see below
Autocad - if you have it, you can use it!
GCode Software
I use the software Cut2D http://www.vectric.com/WebSite/Vectric/cut2D/c2d_index.htm to generate gcode from inkscape files or autocad files.
Machine control software
EMC2 / Axis http://linuxcnc.org/
USAGE
So far I have two videos to watch. More to come, but this might get you going.
and
SAFETY
YOU MUST WEAR SAFETY GLASSES!
DOUBLE CHECK ALL SETTINGS BEFORE RUNNING THE MACHINE
F1 is the abort key on for EMC
THIS MACHINE HAS THE POTENTIAL TO HURT YOU, OR HURT ITSELF!
USE SHARP ROUTER BITS
CHECK YOUR POWER
Notes
From Aaron...
10 IPS is what I typically run plywood at and 20 for jogging and pink foam. Anything higher than that and the machine cat get some pretty nasty wobbles near the ends of the X axis. As for speed of the bit it's a little hard to say since I usually just go off the sound. Blackened cuts and burnt looking sawdust are signs of the cutter going too fast. As for the comment about the chips I normally agree (on all other materials the chips are how I judge my settings) but on wood you just always get sawdust.
Cutter speed too low: More stress on the stepper motors. You can hear them when they're bogged down. More force is transferred from the part into the tool. This risks breaking the bit and/or damaging the machine
Too high: Will cut easy, but the bit will overheat With enough overheating the bit can get dull and start having the symptoms above as well.
With that being said, I usually just start with the speed cranked pretty high since it can temporarily take too high easier than too low, let it start, then turn it down until things sound right.
Issues with this machine: Check the router and the Z-axis assembly and make sure it doesn't have any wobble. Circles are the easiest place to find issues. If your circles aren't perfect circles, then something is wobbling. There will also be a little step between the beginning and end of the tool path. If that's the case try to wobble the router head and tighten what's loose. Next thing to watch out for is stairstepping. This happens when the router isn't pointing straight down. One side of the circle will be smooth, the other will have little steps where each pass was. This is bad (besides the part being wrong) because on the smooth sides it's actually cutting the entire depth depth of the material.
CNC LINKS
http://solsylva.com/cnc/links.shtml
http://replicat.org/generators - I wonder if it is possible to use these to generate G-Code?
