When the bearing holder is disassembled, the balls converge to one side. In the open replacement, the bearing sleeve and jacket is not integrated. The first step, with a vernier caliper to measure the diameter of the bearing jacket bore, for example, is 55MM. The second step, saw a piece of about 20MM width, thickness of about 5MM, about 60MM of iron. The third step, in the center of the iron, washed a center pit. The fourth step, with the center of the pit as the center, with a circle planning a diameter of 58MM of the original arc. The fifth step, in the grinder, the excess of the original arc outside the original arc trimming out. The sixth step, with a hammer to bend the iron plate, (note the bend to be uniform) and measure the length of the iron plate after the hammer bend with a vernier caliper, so that the size of 55.5MM. The seventh step, in the center pit, with 5 mm drill bit drilling. And use M6 tap sets of buckles. The eighth step, to find a through M6 long screw screwed out from the concave surface of the iron bar (just outcrops) The ninth step, the convex surface toward the direction of "dead end" forced into the bearing outer ring ball groove . The tenth step, the long screw to the fastening direction of rotation, this time, "dead end" in the bearing jacket may come out! The eleventh step, if it does not work, take the magnet to suck, the jacket will suck out the twelfth step, no, if not enough, it means the bearings completely scrapped.