Related Glossary Terms
Workholding device that affixes to a mill, lathe or drill-press spindle. It holds a tool or workpiece by one end, allowing it to be rotated. May also be fitted to the machine table to hold a workpiece. Two or more adjustable jaws actually hold the tool or part. May be actuated manually, pneumatically, hydraulically or electrically. See collet.
- computer numerical control ( CNC)
computer numerical control ( CNC)
Microprocessor-based controller dedicated to a machine tool that permits the creation or modification of parts. Programmed numerical control activates the machine’s servos and spindle drives and controls the various machining operations. See DNC, direct numerical control; NC, numerical control.
- computer-aided design ( CAD)
computer-aided design ( CAD)
Product-design functions performed with the help of computers and special software.
- lead angle
Angle between the side-cutting edge and the projected side of the tool shank or holder, which leads the cutting tool into the workpiece.
- metalcutting ( material cutting)
metalcutting ( material cutting)
Any machining process used to part metal or other material or give a workpiece a new configuration. Conventionally applies to machining operations in which a cutting tool mechanically removes material in the form of chips; applies to any process in which metal or material is removed to create new shapes. See metalforming.
Any manufacturing process in which metal is processed or machined such that the workpiece is given a new shape. Broadly defined, the term includes processes such as design and layout, heat-treating, material handling and inspection.
- milling machine ( mill)
milling machine ( mill)
Runs endmills and arbor-mounted milling cutters. Features include a head with a spindle that drives the cutters; a column, knee and table that provide motion in the three Cartesian axes; and a base that supports the components and houses the cutting-fluid pump and reservoir. The work is mounted on the table and fed into the rotating cutter or endmill to accomplish the milling steps; vertical milling machines also feed endmills into the work by means of a spindle-mounted quill. Models range from small manual machines to big bed-type and duplex mills. All take one of three basic forms: vertical, horizontal or convertible horizontal/vertical. Vertical machines may be knee-type (the table is mounted on a knee that can be elevated) or bed-type (the table is securely supported and only moves horizontally). In general, horizontal machines are bigger and more powerful, while vertical machines are lighter but more versatile and easier to set up and operate.
- slotting machine ( shaper)
slotting machine ( shaper)
Vertical or horizontal machine that accommodates single-point, reciprocating cutting tools to shape or slot a workpiece. Normally used for special (unusual/intricate shapes), low-volume runs typically performed by broaching or milling machines. See broaching machine; mill, milling machine.
In response to my Lead Angle column in the April 2019 issue about machining large parts and my attraction to vintage machine tools, I received the following email from Chuck Oloffson, a CAD detailer and former CNC and manual machinist.
“I am just reading your article titled Machining Large in the April issue of CTE and the picture reminds me of the machines I ran at the Chicago Transit Authority’s West Shop on Maypole Avenue. They had old, old lathes, a shaper and several other old machines that we used to machine tons of different things. One had a table that held a full section of railroad rail, which if I remember right was 39' long and we actually had to mill down the rail with hand-made tool steel cutting blocks to match the rail that we were connecting to in profile and height. Some of these rails we were replacing were produced in the 1920s and 1930s and were as hard and brittle as heck. There is nothing like a well-cared-for older machine. I could still hold some pretty tight tolerances with a machine that was over 70 years old and still worked great.”
His email got me wondering about other metalworking professionals’ past experiences and current applications with old machine tools. I still fondly recall the time I visited the machine shop run by Frank Foriska when touring the tool, mold and die shops in Meadville, Pennsylvania, to write an article for the February 2001 issue. At the time, he was still running belt-driven machines to perform general repair work.
If you have a story about old metalcutting machines that you’d like to share, I welcome hearing about it.