Here is my latest project. It was a Dahlgren System 500 in its previous life. I have modified it by the following.
1: Removed the air operated Z-Axis and replaced with a Stepper driven Z utilizing the origional Engraving spindle. In this configuration it will use the T-slot table measuring 24" x 20" with about 1in of Z-axis travel.
2: I built another dovetail mount and added 4in travel delron slides. To this I mounted the stepper and a mount for the trim router. I then only have to slide in the router assembly, remove the T-slot table and replace with a drop table made of .25in aluminum and this gives me a total of 4in of Z-Axis travel. This also allows for a vacume system to remove dust and chips.
3. I am using the origional SCU unit (engraver control) enclosure and the powersupply. I gutted the other electronics and added three API CMD-260 microstepping drives as well as a PMDX-120 Opto-Isolated Breakout board. This drives the steppers at just under 65Vdc.
4: All the mechanical retrofit is done, I just have to connect the steppers and hook up the limit switches and it is ready to go.
5: All this is under a 1/2 in Plexiglass enclosure for dust and sound control.
More photo's of this project are here:
http://stickman4.homestead.com/dahlgrenphotos.html
Alan T.