Quote Originally Posted by Jonathan View Post
The only thing this size ballscrew is good for is maybe a big milling machine or lathe. For other machines, like CNC routers, the forces on the ballscrews are so low that you don't need the slight increase in stiffness gained from using a RM2005 screw
Its not slight when your spinning them at 1000rpm+ At 1.45m I've got a 1610 on the Y axis and it just starts to show whip at 10m/min, at 14m/min its like jelly! You won't run at these speeds of course but for cutting wood you want in the range of 4-7m/min depending on the cutter dia and flutes along with DOC. Unless of course your spinning the nut but I'd still go 2010 at those lengths anyway. The cost difference is minimal for the added peace of mind.

Presumably John S has a big machine to convert...
Or he's chopping them up into lots of little screws ;) More likely though is he'll put them in his cnc spares stash and leave them for a rainy day. The man has enough parts to set up a cnc factory.