SBR20 Linear Rail 500 mm

grabcad

The dimensions for this model were taken directly from the inexpensive Chinese rails commonly found on eBay and Amazon. Although this model is only 500 mm long, the measurements were taken from two 1800 mm long rails, tested at several different positions along their length for accuracy. I found the main bearing surface to be very accurate in diameter. The extruded aluminum base is not as accurate, where the measurements varied by a few microns. The spacing of the mounting holes is not accurate at all, with some holes being up to +/- 2.5 mm from where they theoretically should be. I have included the .f3d file so the dimensions can be changed in Fusion 360 if necessary.