Mill Table 00
I wanted to sketch up a rough version of my two-axis mill table to see what clearances need to be considered, as well as where I need to pay special attention to accuracy, and simplify the design. Here's what I came up with today. A few of the shapes are largely just placeholders for more intricate parts. For instance, the way mounts will need some capability to make minute adjustments to calibrate and square the table. Also, the AB nuts will be proper, spring-loaded, self-adjusting, machined Delrin nuts (not just tapped blocks of Delrin).
The PTFE bearings is where I'm saving a ton of money. Instead of a complex profile on the ways, I've decided to run round stock along the axis and simply drill holes in some short strips of PTFE. The load is spread out across four separate bearings (per table), and is completely limited to only movement along one axis. The bearings will be accurately drilled to fit precisely around the way, eliminating any play in the table.
The X-table will be a simple structure made out of aluminum solid square stock.
Where the threads protrude, I will build some simple motor mounts out of large rectangular stock. The motors will be coupled to the threads (turned down) via a custom motor couple.
Finally, on top of all this, I think I'm going to build a custom work surface with the T-channels to help clamp the material down. It won't be perfect, but more than adequate for my most demanding work (PCB routing).