Reconfiguration of escapement

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Brass 3 train (11).JPG (605525 bytes) A three legged gravity design, this type of escapement required a huge amount of weight drop since it turned at such a rapid rate. This is a shot of the escapement as found. Again, it is difficult to associate this work with that of the frame and movement wheel work. It is a clumsy, severely deficient design.
Brass 3 train (23).JPG (508402 bytes) Look at this vague attempt at making an adjustable gravity escape fly fan clutch. The rest of the fly construction was no better.
Brass 3 train (25).JPG (547497 bytes) The original gravity arm locking pallets had white stones, probably agate. An attempt at a better level of quality.
Brass 3 train (26).JPG (584860 bytes) One of the three legs of the gravity escapement was broken. Note the crude attempt at a repair.
            Brass 3 train (27).JPG (540379 bytes) The overall workmanship is rough. The design displays a poor sense of proportion and balance - in short it's clumsy - if indeed it ever really worked.
            Brass 3 train (44).JPG (586981 bytes) A final parting shot as we bid farewell to this sorry state of affairs.
Brass tower clock-Saff (6c).JPG (361039 bytes) Our first design was to have the overall shape of the gravity escapement follow the upside-down heart shape originating in the going train frame. It is already reflected in the pendulum design. Due to technical reasons, chief amongst them the desire for a large set of anti-friction wheels to be used as our escapement impulse pallets, we abandoned this.
               Brass clock-escapement-Saff (5).jpg (247930 bytes) The final design is developed incorporating the anti-friction wheels. Other gravity escapements have used roller pinions positioned on the escape wheel to reduce the friction point between the gravity arm and the impulse pins of the escapement. Here we have a solid cam instead of pins or roller pins, but use large wheels to greatly reduce friction. An additional benefit is that it is for more visually interesting than any other design I've ever seen. I have Donald Saff to thank for this idea as represented by the drawing he sent me (below, left).

The original pendulum was a 1 1/4 second, too long for the movement to be viewed at a comfortable height. The fact that we altered the gravity escapement from three legs to four gave us the opportunity to shorten the pendulum. Several design iterations were contemplated changing various wheel and / or pinion counts. The last drawing was best, where only the escape wheel and it's pinion needed changing. The pendulum was made to fit the wheel counts resulting in a pendulum that beats just slightly longer than a standard 1 second.

     Brass clock-escapement-Saff.jpg (275884 bytes)    Brass clock-escapement-Saff (2).jpg (227640 bytes) Brass clock-escapement-Saff (4).jpg (213385 bytes) Brass clock-escapement-Saff (3).jpg (211881 bytes)
Brass tower clock-Saff (47).jpg (431282 bytes) Recreated gravity escape fly fan.
Brass tower clock-Saff (50).jpg (580449 bytes) Overall shot of the escapement.
Brass tower clock-Saff (70).JPG (858788 bytes) Locking jewels shown. The escapement is fully jeweled; impulse, locking pallets and pivots.

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