Long time follower, first time poster. I am wanting to scale my CNC up to 4'x8' just as many others are and some have managed to do. I haven't been able to find an affordable solution for linear rail that will provide enough rigidity to handle heavy cuts. I designed a custom extrusion that is essentially a larger openbuilds rail. Would anyone ender be interested in ordering a couple meters for a heavy duty machine? I have a couple concepts I have been kicking around and wanted some feedback. Going from the current 5-series (M5 hardware) profiles to 8-series (M8 hardware) I would also need to find larger v-wheels and supporting hardware. I'd like to hear if anyone has experienced similar issues when trying to scale up. What do current solutions cost per inch?
There's the alternative option of bolting the current V-slot system to a heavier structural member (square steel box section? Alu extrusion? etc) and thus gain rigidity, but keeping the compatibility of wheel and rail parts. This effectively uses V-slot as a linear component only, and offloads the structural function to another beam bolted to it? I did this a couple months back, in combination with press bent sheet metal - see GitHub - openhardwarecoza/OPHW-HW-OpenCNC-ZA: OPHW-HW-OpenCNC-ZA - check the renders of the V2, despite just using 20x20, we had a really rigid X axis with , if I recall off the top of my head, a 140mm spacing between the top and bottom wheels.
Very clean design! Who did you use for the low volume sheet metal parts? What made you decide to switch from linear ball bearings to the v slot rail? I am looking to do a machine that's larger than existing v slot extrusion lengths. I am concerned about butting two rails against each other. Going off your sheet metal idea, with a heavier gage sheet bent at a 45 degree angle, there would be a v rail profile on the top point.
