Here is the drawing of the parts that make up my own design for a motor coupler. It is based on the Oldham style coupler in principle but utilizes common flat sheet materials and dowels to construct an easy to make coupler that will work in situations where the motor and screw are not perfectly aligned. I used this design on the first CNC router I made a couple years ago and it
has functioned fine on the Z axis since it was installed. If you have a CNC machine this will be simple to make and you can use the materials you have on hand and upgrade later if needed.
Modify the mounting hole sizes to fit your motor and screw shafts and the obround slots and dowels can be changed to fit what you have also. This is my simple 2D alternative to spending
more for the available couplers and helped me save some cash for motors and electronics that I can not make. I hope this helps someone get their axis coupled and running and would be interested if hearing feedback from anyone that used this design. I have some pictures to go along with the design that may help visualize how it all goes together and how it looks when assembled to the machine. I am very happy with the results and hope it is of use to someone else.
I did my drawings in VcarvePro originally and used it for the toolpaths and to cut the parts. The second operations of reaming and drilling were done with a drill press but could be managed
with a hand drill if done carefully. You will also need to do some hand tapping for the set screws and the bosses could be riveted or screwed to the discs of the assembly. I use Mach3 for
my controller and the Mach2/3Arcs(inch) post processor in VcarvePro.