Tapers and Taper

A taper may be defined as a uniform change in the diameter of a measured along its axis. Standard or Inch tapers are expressed in taper per foot, taper per inch or degrees. Metric tapers are expressed as a ratio of 1mm per unit of length; for example, 1:20 taper has a 1mm change in diameter in 20mm of length. A taper provides a rapid and accurate method of holding tools such as twist , centres, bits, and .

Self-holding tapers, also known as morse tapers. When seated properly they will remain in position because of the wedging action of the shallow taper angle.( twist drills, lathe centres, drill bits, and reamers)

Steep tapers are also known as machine tapers. These are used mainly for alignment of milling machine accessories. A steep taper has a key-way drive and uses a draw-in bolt to hold it securely in the milling machine . ( head, drill chucks, fly cutters, and cutter arbours)

Taper Turning

Taper turning on the lathe can be performed using three methods.

1. By offsetting the tailstock. 2. By means of a taper attachment set to the proper taper per foot or angle. 3. By adjusting the compound rest to the angle taper. Best for cutting .

Questions: 1 Define a taper. 2. Explain the difference between self-holding and steep tapers. 3. List some examples of tools that have a Morse Taper. 4. List some examples of a Milling Machine Taper. 5. List the advantages for each of the three methods of a taper on the lathe. 6. How are self-holding tapers separated? 7. Sketch what a taper looks like. (Look in the tool crib!)