since I have to wait for more pieces to arrive today, I did more work on the design.
1) overview looking toward gantry and Y-car
2) top view of double Y gantry
3) closer view of Y-car
The Y-car will be a single instead of the double design because the extended carriages are not wide enough unless I add another piece of 1530 to extend the length to 12". I still havent' worked out the details on the Z axis yet. Not sure if the stepper motor will be fixed to the Y car or a moving part on the router support plate.