Adopted Build - my first CNC router

[EddyCurrent]

The Hiwin bearings I used needed the plastic keeper in place otherwise the balls fell out, I found out the hard way. I found that by being careful the bearings would slide onto the rail if it was horizontal or vertical but in all cases the plastic keeper must be kept pressed up against the end of the rail leaving no gaps for the balls to escape. I can't remember if this applied to both the 15 and 20 sizes but it certainly applied to the 15's. Having them well greased helps to keep the balls in place.