Our CNC Milling Machine is based on Joe's CNC plans, and was built by Trevor Taylor, Lloyd Engebretsen, Bill Sandidge, and countless others. The working area is approximately 48" x 52", and the cutting tool is controlled with Mach 3.
Toolpaths for the CNC are typically generated in either VCarve or Fusion 360, but any software that can produce Mach 3 gcode should work.
VCarve is great for generating toolpaths for relatively 2D designs. It has an easier learning curve relative to Fusion 360, which means you can get cutting sooner.
Decatur Makers has unlimited licenses for the makerspace client of VCarve Pro. This version is limited in that it will not export GCode to be interpreted by Mach 3. Click here to download the trial version of VCarve Pro. Contact Trevor Taylor, George Breeden, Michael Fletcher, or Chris Goode for the code to convert the trial version to the makerspace version.
For a quick VCarve tutorial, head over here.
When you generate toolpaths in VCarve, you will need to specify the bit you are using. Click here to download the Decatur Makers tool database file, DecaturMakersbits.tooldb, which you can import into the toolpath in VCarve.
Fusion 360 is a fully-featured CAD program that also allows for generating toolpaths for our CNC router, as well as many other CNC applications. It is free for hobbyists; look for a Start-Up License on Autodesk's website.
One of our members, Chris Goode, has put together a series of videos showing the process of creating 3D shapes and generating gcode in Fusion. Here's a link to the first in the series.
A library for Fusion 360 is coming shortly.
Use of the CNC is restricted to members who have demonstrated their mastery of the machine. This is done by producing gcode in VCarve or Fusion 360, then reaching out on the #cnc Slack channel to be shown how to load your work piece and gcode on the machine.
Currently there isn't a class to walk you through this, but that may change once we figure out a better way to handle classes for it.
Turn on CNC Power switch (leftmost switch on the right side of the CNC)
Turn on computer, login and launch Decatur Makers CNC
Click Reset to exit Estop mode
Click Ref All Home and wait for the machine to home
Secure your stock with clamps and put the touch plate on the zero corner of your stock; PLUG IN the touch plate
Attach your bit and move spindle above the touch plate, about 1/4”
Press Z on the XYZ section to zero the Z axis above the plate
Move the bit and lower into the hole in the touch plate
Click the yellow crosshairs in the touch plate test area; hold onto the touch plate until the XY touch test is finished
Move the bit over the top of the touch plate and press the yellow Z- arrow
Remove the touch plate and press Goto Z to confirm your zero position
Press Load G-Code and load your G-Code
Turn on Spindle power switch (rightmost switch on the right side of the CNC)
Open the baffle to start the dust collector.
Click Spindle CW, and Cycle Start, then Cycle Start again after the M6 tool change line (you should already have changed the tool to your bit)
The purpose of the reservation system is to save people trips to the space when someone is making long cuts or when it is reserved for a class. It is NOT to make sure you have exclusive use of the machine.
It's your responsibility to be aware of when the machine is reserved through Calendly and/or the Google Calendar (the two are connected). Those who have reserved time have the right to kick people off the machine (politely, of course).
For cut times less than 30 minutes, no reservation is necessary. The one rule for these short cuts is don't be a jerk. Jerk behaviors might include: hogging the machine when others are waiting and when you both have minimal setup time, reserving the machine while someone else is on it to kick them off, passive aggressively glaring at someone using the machine when you want to be using it.
Cut times over 30 minutes, or cuts requiring significant setup time, have to be reserved. Reservations are made in 1 hour increments through the Calendly link below. Only outreach and classes can reserve time during peak hours, such as late afternoons during the week and midday on the weekends. This also means that there shouldn't be long cuts during peak times. After 5 minutes, no shows forfeit their entire reservations. Time cannot be reserved more than a week in advance. This is because people are likely to forget.
Because this wiki is public, it's not prudent for us to list the private links to the reservation utility and calendar here. Please ask other Decatur Makers CNC users in person or look at the pins on the Decatur Makers #cnc Slack channel for the link.