06-19-2012, 04:49 PM
I wouldn't use the slots as lifting points. I have your concern of them breaking and have heard of it happening. I think I'd use the existing bolt holes on the ends of the table once you've removed the leadscrew and handwheel assemblies and mount a plate or something using those threaded holes. I'm not a mechanical engineer so this is just based on my gut feeling and paranoia about breaking those slots. 
Ed
Ed