and ended up gutting out the Centurion IV control and servo motors, replacing it all with something more modern. It did work (sort-of) when I got it, but there was no way it would execute a G-code program written by a modern CAM system. We tried to set up drip-feeding, but the ancient computer just wasn't up to it (I think it had about 4 mb of RAM). Also, every time I'd punch a button, I'd hear the sound of ancient plastic crumbling.
If the seller says it will run your programs, why not show up with one and see how that works before plunking down the cash? Like the man said - "Trust, but verify"...
That said, if you are up for a retrofit project, you could do a lot worse than a solid piece of old iron like that to start with. The rebuilt head is a definite plus (we're still looking at doing that to our Beast) and if the ballscrews are in good shape they're worth the price of admission right there. (But don't tell the seller that - he's probably more interested in getting his floor space back than in getting top dollar for this machine...) And like you say, having his help with all this is worth a lot.
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