Chuck
A mechanical contrivance for holding work in a lathe. True chucks are the most important adjuncts to a watchmaker's bench. A good lathe and untrue chucks will result in inferior work, while a cheap lathe with true chucks will permit of some good results. Chucks hold the work truest that come the nearest fitting the hole in them. Trying to hold work too large or too small, will soon get them out of true, and often make the workman dissatisfied with his chucks, his work, himself and his lathe. Wax is the only sure thing for fine staff and pivot work, although there are many substitutes that do very well, and with the aid of them a good workman can turn out a very fine job. With a good lathe, true chucks and sizes to suit, and a reasonable amount of practice, first class work can be done with split chucks. One chuck or tool of any kind seldom does all kinds of work and does it well. Fig. 65 is a good example of the modern split wire chuck, such as is furnished to go with all American made lathes.
The table of American wire chucks on page 79 will prove useful to those persons who contemplate purchasing chucks for lathes of foreign manufacture.