> Having measured the threaded shaft, I find it to be approx. > 7/16x32. This is a size I never heard of but I will need to > find a tap to make the knob insert. Likely there are cheaper sources; but McMaster-Carr carries 7/16-32 taps. http://www.mcmaster.com/nav/enter.asp?pagenum=2345 (near the bottom, under "special thread taps") Randall