Purchased a Charter Oak Automation Milling Machine a few months ago and wished to install an inexpensive DRO (Digital Readout) Option.
Found some AccuRemote brand Digital Readouts online that measure to an accuracy of 0.001" over 24" which is certainly good enough for my projects.
It was kind of the Chicken before the Egg ... or maybe the Egg before the Chicken ... because the DRO units would be helpful when machining their own mounts out of aluminum.
Decided I would make some quick hand-made DRO mounts and then later machine the final versions out of Aluminum using the Milling Machines accurate XYZ axis DRO units.
Made the first DRO mount by hand out of Steel and then decided to use the 3D-Printer to make the other 2 mounts out of 3D-Printed ABS plastic.
Used a Chrome Shaft off of an old Copying Machine to make the inner Z-Axis DRO slider.
The design of the 3D-Printed mounts and how they bolt onto metal makes them very strong and stable.
So far they have been holding to the accuracy promised by AccuRemote
Can still use the original inch markings on front of the Milling Machine because the bottom of the DRO rests on the Zero inch marking.
The main reason I chose to use these individual DRO units is because during the hot Las Vegas summer temperatures I can easily unplug and bring the DRO Readouts into the house.
Probably not the best Digital Readout system but certainly works for my Milling Machine projects.