hello all, I am going to build a plasma table, and piecing together what all I need.

I am planning to make the table 4' x 8'. At this size, linear ball bearing guides become very pricey. I was clicking thru mcmaster's and saw these on page 988 http://www.mcmaster.com/ctlg/loadpag...+Motion+Guides



would these be sufficient for guides?

also what diameter ballscrews would I need for 4 x 8 foot to avoid whip?

i noticed the end mounting blocks for ballscrews are quite expensive as well, is there any cheaper way to get around having to use these?

thanks
tom