New CNC build gantry questions

[Kitwn]

Jazz,
There are lots of different profiles out there of differing cross section and strength at the same outer dimensions. Can you give us some details of the profile you use, especially the weight per metre? This would allow a reasonable comparison between manufacturers.

Kit

[JAZZCNC]

Jazz,
There are lots of different profiles out there of differing cross section and strength at the same outer dimensions. Can you give us some details of the profile you use, especially the weight per metre? This would allow a reasonable comparison between manufacturers.

Kit

Yes, no problem. I use 2 different types equivalent to ITEM and Bosch Rexroth profiles depending on machine size.
On the smaller machines,(up to 1000mm width) I use Bosch Rexroth equivalent 45x90 with a 10mm slot. 4.2Kg/M

The reason I use this type is that the slot spacing just happens to match the bolt spacing of BK12 bearings so it makes fastening easy.

On the wider machines, I use ITEM 120 x 80 (10.8kg/m) or 160 x 80 (13.5kg/m) with an 8mm slot. This does mean plates have to be made for mounting Bk bearings.
I prefer the 8mm slot because gives a more flat area for the linear rails to sit on when using 20mm rails The BR 10mm slot doesn't leave a lot of room spare.