Because I'm a nerd...
Original motor was a 1200 RPM motor. So I knew the step speeds on that motor setup. So I created a simple spreadsheet that would convert that into my mechanical ratios. Then with the new 1800 rpm motor, I was able to calculate my 1:1 speed with the baseline 60Hz frequency on the phase inverter. From there, I took 5 hz steps from 70 down to 20 and calculated speed points, sent the chart to the UPS store and they printed and laminated it for $4.52. Voila, speed chart for each step pulley at each frequency. This will suffice until I figure out how to install my tachometer.
Original motor was a 1200 RPM motor. So I knew the step speeds on that motor setup. So I created a simple spreadsheet that would convert that into my mechanical ratios. Then with the new 1800 rpm motor, I was able to calculate my 1:1 speed with the baseline 60Hz frequency on the phase inverter. From there, I took 5 hz steps from 70 down to 20 and calculated speed points, sent the chart to the UPS store and they printed and laminated it for $4.52. Voila, speed chart for each step pulley at each frequency. This will suffice until I figure out how to install my tachometer.