MILLING MACHINE OPERATIONS - OD1644 - LESSON 1/TASK 1
If the milling machine in the shop is labeled No. 2HL, it has a table
travel of 28 inches; if it is labeled No. 5LD, it has a travel of 50 inches.
The horsepower designation refers to the rating of the motor which is used
to power the machine.
The model designation is determined by the
manufacturer and features vary with different brands. The type of milling
machine is designated as plain or universal, horizontal or vertical, and
knee and column, or bed. In addition, machines may have other special type
designations and, therefore, may not fit any standard classification.
Milling Machine Accessories And Attachments
Milling machine cutters can be mounted on several types of
The machinist must know the devices, and the purpose of
each to make the most suitable tooling setup for the operation to be
performed. Technically, an arbor is a shaft on which a cutter is mounted.
For convenience, since there are so few types of cutter holders that are not
arbors, we will refer to all types of cutter holding devices as arbors.
Milling machine arbors are made in various lengths and in standard
diameters of 7/8, 1, 1 1/4, and 1 1/2 inch. The shank is made to fit the
tapered hole in the spindle, the other end is threaded.
The threaded end may have left-handed or right-handed threads.
Arbors are supplied with one of three tapers to fit the milling
Standard taper, the Brown and Sharpe taper, and the Brown and Sharpe taper
The milling machine Standard taper is used on most machines of
recent manufacture. It was originated and designed by the milling machine
manufacturers to make removal of the arbor from the spindle much easier than
will those of earlier design.