Intro to my CNC build

Hello everyone!  I'm finally getting around to creating a way to show people my projects and what better way to start than with an intro to the CNC machine I've been working on.

I (along with Tom my downstairs neighbor) am building a 3-axis CNC milling machine. CNC stands for Computed Numerically Controlled, it's a fancy way to say "Computer Controlled" and a milling machine is a machine that cuts a solid chunk of material into some sort of finished piece.  This could be as simple as drilling a few holes in a piece of wood, or as complex as machining the precise blades of a turbocharger (and much more complex things that I can't think of off of the top of my head).  The end result of this project will be a router (or Dremel tool) that can be controlled in 3D space by a computer.

We'll be building a gantry style CNC machine which is well suited for cutting softer materials like wood, foam and plastic and is relatively easy to build at this scale.  We're shooting for a cut area of around 2.5 ft. x 1.5 ft. x 6 in.  This site has the basic design of what we're looking to build and a lot of great details, like the linear bearing system.  I used this build as a reference when creating the rough design of our machine.

Now, on to the pictures:

Here we have the grooves cut in the tabetop of the machine.  The sets of grooves must be parallel to each other to ensure smooth operation.  I think we got pretty close on this one, about 1/16 off at the very most.

 Building the base.  It's oriented upside down.  You can see the metal brackets we used to secure it.  This was done for simplicity.  We also wood glued everything.

Clamping the grooves for the bottom rail.  These also have to be parallel to each other so we cut them a little thin so we had room to adjust before gluing and screwing (hot).

Here we've attached the aluminum angle.  the angle sits in the grooves to keep it straight and prevent it from bowing out when it's screwed in and force is applied to it. Tom had a poor man's drill press with a notch in the bottom that made drilling the aluminum much easier.

Here's the NEMA 23 mounting hole for the X-axis stepper motor.  The stepper motor will turn a lead screw running down the axis which will have a nut attached to the gantry threaded on it.  I'll explain in more depth how the drive system works later on.

Here we can see the orientation of the motor mount with the X-axis.  We've also attached a chunk of wood along the axis to prevent the sides from flexing when a load is applied to the lead screw.

That's all I've got for now.  I'll do a post on the electronics soon since those are already finished.  Please leave comments and questions, I know I'm probably leaving out a ton of details.