Eccentric spacer, 6.35mm, for plastic/aluminium carriages

This is a version of the MakerSlide eccentric spacer optimized for plastic carriages.  It is wider (10 mm instead of 8 mm), has the bottom edges chamfered, and has a longer neck (2.9 mm instead of 1.6 mm).  These features make it friendlier to soft surfaces, such as 3-D printed MakerSlide carriages.  It is the same height (6.35 mm, 1/4") as the standard MakerSlide spacer, and requires the same size hole (7.14 mm, 9/32").  The inner hole is 5 mm diameter, offset 0.8 mm.

This spacer is also suitable for aluminium carriages at least 3 mm thick.