This is an XY table for a desktop dremel-powered vertical mill. The rest of the assembly isn't completed yet, but I after seeing NickAmes' work ( http://www.thingiverse.com/thing:2956 ), I figured I should post this and see if it might be useful to his project. I still plan on finishing this when I get a chance, but collaboration can't hurt.
The basic idea here is that the X and Y stages are the same part and can be assembled into as long a stage as you like. X and Y stages are held together by a pair of M3 all-thread rods which are tightened by nuts on each end to place the stage in compression. each slide has a captured M6 nut which engages an M6 all-thread rod with a handle something like this:
The slides are keyed together with 3mm keys (not yet modeled) and fastened by 4-8 M3 SHCS. The whole affair is attached to the table or bench by screws through the Y-axis endcaps. T-nuts (not yet modeled) would have a captive nut so that parts can be secured to the x-stage. As-is it might suffice as an XY table for an existing drill press, if you have one.
1) These may have to be walked through blender before they can be skeinforged.
1) Print at least 2 of each part (parts have not been skeinforged or tested in any way, but they should print). 3 segments should fit on a single makerbot build stage, and 2 end caps should fit.