PJs, thank you for the feedback. I had fun designing the modifications, but my recommendation for a milling/drilling head addition is not to use a Unimat headstock assembly. I used it because I had a spare Unimat headstock but it has its limitations. The maximum of spindle movement is approximately 0.62" , the 25mm diameter milling head column should be larger and rectangular (loss of registration when moved up or down but I have a solution and will post it), and the spindle thru hole is too small. I learned to work around these limitations and the machine can produce excellent small parts. The smaller the machine, the longer the set up time. I think next time I would adapt something more like the homemade drilling attachment ( Taig Mill ) built by John R. Bentley. He does beautiful engineering and machining for his engines and his tools. You should check out his website.

Thank you, Paul Jones