This was answered by phone.
The answer is the 8 TPI ball screws are 2.8 ratio compared the the standard 20 tpi screws. The theoretical top end of the Pittman motors is 25 ipm at 30vdc. 2.8 * 25 = 70 ipm theoretical top end. 70 ipm = 1778 mm/min. The actual machine result will depend on the gib adjustment and alignments. Probably somewhere between 40 and 60 ipm will be the result. This may need to be geared down with a timing belt to get enough power for heavy cutting in aluminum or steel. I would try it direct first, then add a belt reducer, only if necessary.
Fred Smith - IMService
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