There are some plastic cap mould making ways as follows:
PLANING
The metal-removing process of planing takes place when the cutting tool moves by a straight back-and-forth motion with respect to the work, or when the workpiece moves in a straight back-and-forth motion with respect to the tool, which is stationary.
Four types of machine tools operate according to one or the other or both of the above principles: the planer, the shaper, the slotter or vertical shaper, and the broaching machine.
SHAPER
In shaping, the tool is reciprocated and the feed of the steel for cap mould manufacturing is represented by the width of the cut. Shaping is particularly suited for small work in view of the design and construction of most shaping machines. (It is seldom used to machine work more than two feet square.) Shaping entails producing flat surfaces in horizontal, vertical, and angular planes. In addition, internal surfaces and odd-shaped surfaces can be shaped.
The work is usually clamped in a vise fastened to the table. The typical toolroom shaper has a universal table that can be tilted to 15° and swiveled through an arc of 180°.
Because of its flexibility, the shaper is considered a basic machine tool. It is widely used as a toolroom and die shop facility and, in view of the rate of metal removal, is of limited use in large production runs.
VERTICAL SHAPER
The vertical shaper, commonly known as a slotter, is similar to the shaper except that the ram is reciprocated in a vertical slide. The stroke range in vertical shapers is from 6 to 36 inches. For shaping clearance, the ram may be adjusted to move at an angle to the vertical.
Circular tables for holding the work are usually standard equipment with the vertical shaper. Round shapes can be generated by rotating the table by power feed； however, this is usually not the most economical technique for producing circular shapes.The vertical shaper is used primarily for slotting or key-seating operations.
PLANER
The planer is used primarily in the machining of flat surfaces, where the magnitude of the work is such that it is impractical to machine on a shaper or milling machine.
The planer has a long horizontal bed upon which the work-holding table slides with a reciprocating motion. Above the work table, the tool head (or heads) is mounted on a horizontal crossrail. The tool head is mounted on a slide to permit vertical adjustment so as to set the cutting tool to the correct depth. The crossrail may be adjusted vertically in order to accommodate various sizes of work.
APPLICATION OF THE PLANER AND SHAPER
As mentioned previously, the shaper finds most application in the plastic cap mould shop. It is usually more economical to use a shaper rather than a planer for small work because：
- It is faster and more simple to operate.
- It is a less expensive piece of equipment and uses less power.
The planer is adapted for machining flat surfaces on large work. Similar to the shaper and the milling machine, vertical, angular, and horizontal surfaces can be cut. Work should be routed to a planer if：
- Heavy cuts are required on large flat surfaces.
- The material to be cut is relatively hard (large steel castings).
- Accurate finish is required in such work as slides and guides.
SHAPER AND PLANER CUTTING TOOLS
Shaper and planer tools are similar except for size, the planer tools being considerably larger in order to accommodate the larger work.
Because of the intermittent cutting action of both the planer and shaper tool, toughness is an important criteria in tool-material selection. Consequently, high-speed steel is most commonly used； However, carbide-tipped tools are used for taking light or finishing cuts. It is important that the depth of cut, even when using carbides, be greater than 0.010 inch so as to get a cutting rather than a rubbing action.
The front clearance angle should be about 4° so as to prevent rubbing of the back of the tool on the work. A side clearance of 3° is usually considered adequate. In the cutting of mild steel, a 12 to 15° side rake is advocated. For cast iron where less shearing action is needed, 3° side rake is recommended. The back rake varies from 0° for roughing cuts to about 2° for finishing cuts. With these small rake and clearance angles, the tool is more able to withstand the force of impact at the beginning of each cutting stroke.
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