(1) Assemblies having vertical movement shall be blocked and braced in a lowered position. Those capable of
moving transversely shall be centered for blocking and bracing.
(2) When heads, motors, tables, rams, and similar movable components are activated by hydraulic systems,
positioning must be accomplished prior to disconnecting from the power source.
(3) Machine tools with movable heads and hollow spindles shall be secured by placing wood blocking between
movable and fixed heads or base castings with a single tie rod assembly through the hollow spindles (fig 8-2).
(4) Items having solid spindles shall be secured by double yoke tie rod assemblies (fig 8-
2). In blocking of spindle assemblies, blocking will be to the spindle housing, not to the spindle itself.
(5) Wood blocking between movable and fixed assemblies or bases shall be secured in position to avoid
dislodging due to material shrinkage.
(6) Tables or heads which have roller bearings in contact with the ways shall be blocked so as to remove the
weight from the bearings to prevent brinelling of the ways. Indicate on a tag that tables or heads have been blocked to
remove the weight from the bearings and that the blocking must be removed before operating the machine. Attach a tag
to the machine in close proximity of tables or heads that are blocked. An alternate method is to remove the bearings and
insert filler pieces of soft material such as brass, bronze, plastic, or soft steel.