OK this thread is dead and old so time for an update. I've spent some time collection parts and the gantry parts from a robotic tape library seem to be a great start. I opted for the easy route and called Tom for his Dragon Cut CNC kit which makes that part much easier.
This update covers about 5 evening worth of work over the past 2-3 weeks. The base of the gantry support is built using 1.5" and 1" sq stock. The gantry was adapted from the old robotic tape libraries to the support table. The stepper motors from CandCNC.Com were adapted to the Gantry using Aluminum plates. I then built an adapter for the Z axis to attach to the slide I bought about a year ago. More in the Original Post In the link or Below..
After doing all of the above I adapted the Z axis so it would fit on the Y axis slider. This was done by drilling some holes for some "Alignment" pins and some M6 1.0 Metric machine screws. Once all this was done I installed the belt tensioner and belt on the X axis slide and pulled the belt and noticed some deflection on the far end of the X axis so I decided I was going to have to install a Jack Shaft that would drive the other side simultaneous to the near side with the motor on it. The nice thing about this jack shaft is it has a ~2:1 gear reduction on it if the stepper has trouble doing a 1:1 drive. So I made some adapters for the Jack Shaft and installed them so I could still apply tension to the belt. On the far side I had to add a tensioner on the far end so I had to modify the frame a little to handle that.
Now the motors are mounted and the jackshaft and belts installed. I got the Belting stock from McMaster Carr. Now the next step is to hookup the PC running Mach3 and all the Gecko drivers etc so I can test some of the functionality. After that I will finish weld this part and start the support table to hold the steel and the water table to keep the dust down.
Here are the pics.
Motors adapted and gantry just sitting on frame.
Thanks for looking.