Arbor presses range in size from small table mounts of about five pounds to large presses in excess of 500 pounds. Smaller arbor presses may be used by jewelers for insertion of precious metals into small tubes or orifices. Large presses can be used for pushing bearings into precision machinery. Regardless of size, all arbor presses consist of a rack gear that is attached to a long handle. The handle moves the gear up and down. This assembly is contained or held into place by a frame casting. The casting frame can be mounted to a workbench or have a specially designed metal frame made for a stand-alone station. The rack gear is square in design, and is the end that pushes a part into place. A lower press plate that resides on the lower half of the casting frame is where the larger part is placed. Typically this is a movable plate. This plate also has a series of slots built into it for allowing a pushpin to fall through the pressed part.
Place a part on the moveable press plate of the arbor. In this case it can be a bearing assembly, in which the old bearing must be removed and a new one inserted. Turn the part over so the bearing is setting upside down on the arbor plate. Align the bearing with the large hole at the bottom of the press. This will allow the bearing to fall out.
Insert the pushpin into the rear of the bearing assembly so it sets against the backside of the bearing. Lower the square rack gear so it contacts the pushpin. Pull downwards on the handle of the press. Push the bearing from the assembly. The bearing will fall out when enough pressure is applied to the handle. Return the handle upwards to its ready position.
Turn the part over and inspect the bearing opening. Clean the opening. Lay the assembly on the press plate right side upwards. Position the bearing over the bearing opening. Do not force the bearing into the hole. Align the bearing evenly against the sides of the hole.
Use a pushpin that is greater in diameter than the bearing itself. Insert the pushpin between the square arbor and the top of the bearing. Apply a downward pressure to the pushpin through the handle. Slowly apply more pressure and observe the bearing slipping evenly into the cavity.
Set the bearing into place by aligning the bottom of the pushpin with the top of the assembly. The bearing should be properly seated.
