CNC Machine

I haven't posted anything very recently, mostly because I've been busy with a big project. I was building a CNC machine, and just finished it last night! It been quite a while working on it. It started at Christmas - my parents got me all the necessary parts I didn't have - basically some leadscrews and nuts. Just in case you're wondering, I mostly followed the Mantis 9 plans from MakeYourBot.com (which I think was made by some MIT students). It looks like this - 

Mantis 9

    It requires something like only 13 components (which is mostly true) and costs under $100 dollars to build (also only mostly true). I didn't quite follow their design. Here is where my design deviated from theirs: 1. I used 3/4 inch plywood instead of their 1/2 inch because that was all I had at my house. It works fine, but in order to preserve internal measurements, several measurements have to be enlarged by 1/2 inch. 2. I used a Dremel tool instead of their more compact spindle assembly. The Dremel seems to work fine, though it is a little hard to find and actual Dremel-branded one. I want this because real Dremels are cylindrical, making mounting much easier. 3. I used EasyDrivers from SparkFun instead of their A3982 stepper controllers. This was only because I found I couldn't solder small pitch SMD chips. Otherwise, I used the same design.




Concerning EMC2
    EMC2 is the control program that the Mantis 9 uses. It stand for Enhanced Machine Controller and is clearly the second version. It can be found here. What I found really cool about EMC2 was that it wasn't just a program, but an Ubuntu distribution. This means that, when burned onto a disk, a computer will mount off that disk and load all the necessary CNC modules and programs. EMC2's one downfall is that that it requires a parallel port. It works by bit-banging the step and direction information for the motor controllers directly from the parallel port. Here's a diagram to make it a bit more clear - 

See how the parallel pins connect to the headers?

    The computer is using the parallel port just like a microcontroller would use a port of IO pins to control motors or LEDs. Pretty cool, huh? There are a lot of error messages, but I think I've gotten them all, so if any of you are trying this, I love to help someone in the comments!


    Some benefits of EMC2, though. It's incredibly flexible. You can give it not only a G-Code file, the CNC milling standard, to mill, but also .PNGs, .JPEGs, and Gerber files among others. Gerber files are extra cool. If you don't know what they are, they are PCB design files that tell the computer where traces and holes go. I'm really looking forward to using these.


    I'll post some pictures and video as soon as I can get some time to edit the video and load them on my computer. If you're looking at making a CNC or 3D printer, I would definitely recommend looking at the MakeYourBot.org site.