ore distinctly shown, illustrations of both methods are here given.
Fig. 18 shows the popular method, the lower portion of the staff being
all completed and fastened by means of wax, in the wax chuck. Fig. 19
shows the opposite course of procedure. In both illustrations the lines
indicate the amount of wax applied to hold the work. It will be noted
that in Fig. 18 the hub of the staff is enclosed in the wax very much as
a cork is fitted into a bottle, while in Fig. 19 the hub is reversed,
just as a cork would appear were the larger portion within the bottle and
the smaller portion protruding through the neck. A study of the diagram
will readily show that in Fig. 19 the staff is held more rigidly in place
and that a greater bulk of the work is enclosed in the wax than in Fig.
18, although there is less wax used in the former than in the latter.

[Illustration: _Fig. 18._]

[Illustration: _Fig. 19._]

Before proceeding to set the staff in the wax, it is necessary to make
some measurements to determine its full length. Remove both cap jewels
and screw the balance cock in place. Examine the cock and see if it has
at any time been bent up or down or punched to raise or lower it. If so,
rectify the error by straightening it and then put it in place. Now with
a degree gauge, or calipers, proceed to take the distance between the
outer surfaces of the hole jewels and shorten the staff to the required
length. Do not remove too much, but leave the staff a little long rather
than cut it too short, as the length can be shortened later.

[Illustration: _Fig. 20._]

[Illustration: _Fig. 21._]

A very handy tool for the purpose of making these length measurements can
be constructed by adding a stop screw to the common double calipers as
shown in Fig. 20. The improvement consists in the fact that they can be
opened to remove from the work and closed again at exactly the same
place, so that an accurate measurement can be made. The all-important
point in the use of wax chucks is to get a perfect center. If you are not
careful you are liable to leave a small projection in the center as shown
at A, Fig. 21. The ordinary wax chuck cannot be unscrewed from the
spindle and restored to its proper place again with anything like a
certainty of its being exactly true, and if you insist on doing this
there is no remedy left but finding a new center each time. It will be
found more satisfactory and economical in the long run to have a
permanen