It looks like you can get NEMA 24 motors with roughly 4X the torque of a typical printer NEMA 17 for about $100 (3pcs delivered in the US). That should be enough torque to create other issues if you ever used all of it.
Stepping these motors fast enough to get a 10" / sec feed with a 1/4" screw isn't a real easy thing to do. I think that with 1/16 micro stepping, the Z resolution (or x or y since they all couple) will be good enough on a 1" screw. It is indeed resolution and not accuracy in this case. There are a number of things that will contribute to accuracy.
As long as the motors are 24's the 3 to 4A driver cards should handle them just fine. Since they are opto isolated, they will lash into almost any controller board you would want to use. I've already got Mega's and Ramps 1.4's lying around here, so I'd start up with those. Once the Marlin (or what ever) on ARM gets sorted out ... and the Adruino IDE for ARM gets sorted out ... and the control cards for 3.3V i/o to ARM get sorted out ... upgrade to an ARM. Even bought new, the Mega + Ramps is $40 or so. That's not the big item on a $1K parts budget. The ARM world is only slowly coming to printers. One really cool new thing at a time...
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Looking at growing the LISA in X and Y - the arms grow as roughly 2/3 the screw spacing if I read right in a post above. Taking that as an accurate number, for a 600 mm screw spacing one would need 400 mm arms. Those aren't going to print easily on a common printer. Even more so if you put a skirt / brim around them to keep things flat. I'd rather not go to a pair of printed parts mated in the middle with screws, my guess is that they would not be very accurate. Some sort of aluminum bar might work, printed parts plus thread rod might work, neither gets me real excited. Am I being overly concerned here?
Stepping these motors fast enough to get a 10" / sec feed with a 1/4" screw isn't a real easy thing to do. I think that with 1/16 micro stepping, the Z resolution (or x or y since they all couple) will be good enough on a 1" screw. It is indeed resolution and not accuracy in this case. There are a number of things that will contribute to accuracy.
As long as the motors are 24's the 3 to 4A driver cards should handle them just fine. Since they are opto isolated, they will lash into almost any controller board you would want to use. I've already got Mega's and Ramps 1.4's lying around here, so I'd start up with those. Once the Marlin (or what ever) on ARM gets sorted out ... and the Adruino IDE for ARM gets sorted out ... and the control cards for 3.3V i/o to ARM get sorted out ... upgrade to an ARM. Even bought new, the Mega + Ramps is $40 or so. That's not the big item on a $1K parts budget. The ARM world is only slowly coming to printers. One really cool new thing at a time...
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Looking at growing the LISA in X and Y - the arms grow as roughly 2/3 the screw spacing if I read right in a post above. Taking that as an accurate number, for a 600 mm screw spacing one would need 400 mm arms. Those aren't going to print easily on a common printer. Even more so if you put a skirt / brim around them to keep things flat. I'd rather not go to a pair of printed parts mated in the middle with screws, my guess is that they would not be very accurate. Some sort of aluminum bar might work, printed parts plus thread rod might work, neither gets me real excited. Am I being overly concerned here?