3 axis cnc/router bed

[dudz]

Ok... I have the 25mm Aluminium for the bed. I unbolted the original vacuum bed, and noticed straight away that it is bent down on each end where there are no bearing blocks supporting it. 4mm to nothing, from each end to the center !
I took out the 25mm unsupported rails and rolled them on a sheet of glass to check for bend. Seems all ok. The vacuum bed is pretty flimsy. 2 out of the 4 bearing blocks seem to have had their day ( roll a bit rough ). So I suppose I might aswell replace the 25mm rails for supported ones with new open bearings ; SBR20X900 Precision Supported Rail kit 900mm long CNC | eBay

The rail length I need for the X axis is 850mm. Is 20mm rails (as in the link) going to suffice ?
Also the ballscrew seems fine. But as I am replacing the rails, will the height from the 45mm profile (frame) to the bottom of the new Bed be the same for the new rails and the original ball screw bearing ? The new rails are certainly within 2mm (see pdf on ebay link )

[Jonathan]

If you're planning on getting the rails from that seller then you can get 25mm for the same price here, or maybe less here if you send the seller a message. I'd go for 25mm since they have one more row of balls than the 20mm rails, so are correspondingly stronger. Having said that either will be a huge improvement on what you have now.

[dudz]

hmmmm..... I just payed 37 euros taxes for an item from the US which cost 85 dollars.

[dudz]

Ah ha.. probably these : x20 T-Nuts Slot 10 M6 1001 | eBay