- This article is about shapers designed for metal workpieces; for wood applications, see Wood shaper.
- ''For a person who makes surfboards see Shaper (surfboard)
A shaper is a machine tool used for shaping or surfacing metal and other materials.
Shapers have been largely superseded by milling machines
or grinding machines
in modern industrial practice. The basic function of the machine is still sound and tooling for them is minimal and very cheap to reproduce. They can be invaluable for jobbing or repair shops where only one or a few pieces are required to be produced and the alternative methods are cost or tooling intensive. The mechanically operated machines are simple and robust in construction, making their repair and upkeep easily achievable.
Shapers are mainly classified as standard, draw-cut, horizontal, universal, vertical, geared, crank, hydraulic, contour and travelling head. The horizontal arrangement is the most common. Vertical shapers are generally fitted with a rotary table
to enable curved surfaces to be machined. The vertical shaper differs from a slotter
(slotting machine), as the slide can be moved from the vertical. A slotter is fixed in the vertical plane.
Very small machines have been successfully made to operate by hand power
Once size increases, up to a potential 36 inch stroke, the power needs increase and it becomes necessary to use an electric motor. This motor drives a mechanical arrangement (using a pinion gear, bull gear and crank) or a hydraulic motor which supplies the necessary movement via hydraulic cylinders.
A shaper operates by moving a hardened cutting tool backwards and forwards across the workpiece. On the return stroke of the ram the tool is lifted clear of the workpiece, reducing the cutting action to one direction only.
The workpiece mounts on a rigid, box shaped table in front of the machine. The height of the table can be adjusted to suit this workpiece, and the table can traverse sideways underneath the reciprocating tool which is mounted on the ram, the table motion is usually under the control of an automatic feed mechanism which acts on the feedscrew. The ram slides back and forth above the work, at the front end of the ram is a vertical tool-slide that may be adjusted to either side of the vertical plane. This tool-slide holds the clapper box and toolpost from where the tool can be positioned to cut the straight, flat surface on the top of the workpiece. The tool-slide permits feeding the tool downwards to put on a cut it or may be set away from the vertical plane, as required.
The ram is adjustable for stroke and, due to the geometry of the linkage, it moves faster on the return (non-cutting) stroke than on the forward, cutting stroke. This action is via a slotted link or whitworth link.
Cutting fluid may be employed to improve the finish and prolong the tool's life.
The most common use is to machine straight, flat surfaces but with ingenuity and some accessories a wide range of work can be done. Other examples of its use are:
- Keyways in the boss of a pulley or gear can be machined without resorting to a dedicated broaching setup.
- Dovetail slides
- Internal splines
- Keyway cutting in blind holes