Could someone help me out with a calculation please. I have a build with 20mm x 600mm hardened unsupported rods as X rails. The weight of the Z assembly is about 12-14lbs inclusive. Routing will mainly be small wood projects ie. model planes and occasionally some very light aluminium. I need to know the approximate deflection on the rails please. I have tried various calculating progs, but get myself a bit tied up with the different technologies. Many thanks.

Tony