Linear rail for X and Y axes - Lasers

I've built a couple machines with the V-Slot Linear Rails & C-Beam's They work really well For now max length I'd recommend for the C-Beam is

V-Slot is a high quality extruded aluminium profile building block that has an extremely smooth linear v groove rail on all 4 sides

linear slot diffuser cfm chart V-Slot 20x40 Linear Rail​​ V-Slot® Linear Rail V-Slot Linear Rail aluminum extrusion profile is the ultimate solution combining both linear motion and a modular,

linear slot diffusers MGN9 Linear Rail ever so slightly sits in the v-slot of 20mm v-slot extrusions due to the chamfers Common t-nuts can't clamp down on a 20mm