Screw Bezel and Screw Bach Cases. Swing Ring Cases
Assembling Fancy Shaped Cases
The Fancy Shaped Cases come under the class of “snap cases” and are generally provided with a key or pin on the center which fits into a “key seat” or opening on the bezel or back.
In figure 15 is shown a movement in an octagon shaped case with the bezel and back removed from the center. At B is shown the key on the dial side and at C is shown the key seat on the bezel.
In replacing the bezel it is necessary that the key seat be exactly over the key.
On the other side of the center there is a similar key which fits into the key seat on the back shown at D.
Screw Bezel and Screw Bach Cases
The screw bezel and screw back case is one of the most common styles used in open face pocket watches.
In figure 16 I have purposely used a cut of an old style heavy screw bezel and back case in order that you may see more easily the method of assembling it.
As you can see from the drawing the “center” is threaded on each side at B and C. In assembling the case the back E is screwed up tightly on thread C and the bezel D, into which the glass F is snapped, is screwed on B. Each of these is a right hand thread.
The screw bezel and back case is generally abbreviated by the manufacturers and jobbers as S. B. and S. B.
Swing Ring Cases
Figure 17 shows a swing ring case. In this the back is solid – in other words the back and center are all in one piece while the bezel R is a Screw Bezel.
The ring T into which the watch movement is fitted is jointed to the ease at the point S and in taking out or replacing the movement it is necessary to swing the ring out much further than is shown here to get at the case screws and to do this it is necessary to first pull the stem out to the setting position. At the lower edge of the ring you will find a groove or lip in which to place the edge of your case opener. This is necessary as the swing ring fits closely and the edge being flush with the case is hard to start otherwise.
Even then there may be a slight sticking as it is opened due to the stem holding in the movement. If so, you may be compelled to twist the stem back and forth by means of the crown, at the same time pulling out on the swing ring.
In figure 18 is shown a dust proof assembly of Crown, Stem and Sleeve, which is used in many Swing Ring Cases.
At V is a nut which screws down on the outside of the pendant of the case. Inside this nut is a leather washer which together with the solid back makes this style case practically dust proof.
In making any adjustments in the position of the sleeve or to remove the stem and sleeve it is first necessary to unscrew the crown from the stem and then the nut V from the pendant.
Figure 19 shows a case in three parts in which the bezel W is jointed to the back at the point X. The movement holding ring Z to which is attached the pendant, is jointed to the side of the back at Y which permits the movement to be easily fitted. This is a snap case.
Case Screws. Modern Casing. The Hunting Case
Case Screws In the American system of casing movements, the movement was not jointed to the case but held in place by means of case screws. These case screws at first were merely short screws similar to pillar screws and screwed into the top plate so close to the outside edge
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