We spent quite a bit of time researching many DIY CNC solutions. We were looking for something that could be broken down and reused or scaled to various projects if needed. We settled on following this instructable that primarily used T-Slot framing, which made the entire project much like an industrial erector set!

Frame Assembly

 First we cut off 7" at the end of our 4' long T-slot 2x1's for the Y Chassis. We then placed the remaining 2x1 T-slot directly on top of the 1x1. When we assemble parts on the T-slot, we found it much easier to put the screws on first then just slide them down the rail. The screwed the frame down to a large piece of plywood while we worked on it


Y Chassis and Brackets

  We assembled the Y chassis with screen door rollers. They were a bit stiff out of the box but a little lubricant did wonders to get it rolling smoothly. I reccomend working out the bracket, belt, and pulley system first, as the sliding X and Y axis both have to be woven between the belts.

  We drilled channel aluminum to make the brackets, two holes for screws and two holes for holding the bearings and rod setup.


Motors and Potentiometers

  Once we had all the pulleys on, it was just a matter of adjusting and tweaking till every was sitting right. Use a box or some small supports to aid in lifting the rails off of eachother while asjusting the wheels. You will likly be disassembling and reassembling many of the parts to fit everything into its proper place.

  We looked into many different ways of mounting the motors to the frame, but ended up going with a flexible mounting as shown in the instructable. Although the flexible shafts seemed fine, we opted for just tubing. We used some extra brackets we bought at the hardware store to finish mounting the potentiometers.


Underlying Map

  Throughout the frabrication, we have brainstormed and tested a multitude of materials to take the shape of the underlying map. We thought of everything from painted wood or foam to layered sugar and heating lasers. We heavily experimented with lasers and UV or heat sensitive inks, but in the end they didn't give us the effect or quite work with the piece. We ended up on settling on a laser cut trough that is filled with sand then painted, so once the surface is agitated, the lighter underlying layers are exposed.


 After that it was just time spent tuning the motors. We used Pololu JRK controllers with Lyxnmotion Gearhead motors because stepper motors seemed a bit underpowered for this application. Our group would love to thank CarlS and his T-Slot XY table instructable that did most of the heavy lifting for us. His project goes into the exact parts we used and made the entire project get started smoothly. Thanks for all the help that the SJSU and CADRE community has provided. He's a quick clip of a setup similar to our doing some test runs so you can get an idea of how the thing runs:


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