This doesn't sound like a great business model to me. The trouble with retrofitting old machines is that each one is different. Even if you stick to, say, Bridgeport Series 1 machines, the ones you'll get will all have been used - and abused - in different ways. Shops tend to set up a machine to do one particular operation over and over, which wears them out in certain places. Just diagnosing all the problems of each machine you get in would be a lot of work, not to mention fixing these issues - repacking the ball screws, scraping the ways, replacing bad spindle components - it would be a big nightmare.
It would be easier if you started with something new, even if it was a cheap Chinese machine, and went through it carefully, regrinding the ways, replacing the screws, and fitting them with better spindle bearings. At least you'd know what needed to be done, and it wouldn't be a new adventure each time. Of course, starting with your own new castings would be best of all; then you'd have something nobody else did, and you could make it the way you (and your customers) really wanted it.
Andrew Werby
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