Monday

C40B WT in ClockDoc archives

*
There are a number of fine images of a C40B Waiting Train installation in the ClockDoc archives. The larger 'B' movement is most easily recognisable by the greater size of the hand setting dial/bevel wheel cluster [on the right] and matching 'shoulders' at the top of the mainframe. The far more common, smaller C40A frame was usually asymmetric. With a curve or indented straight section in the casting just above the power electromagnets. This symmetry only applies to the earlier C40B movements. Later WTs have a distinctly stepped frame with an open platform for the bevel wheel cluster.

I have borrowed an overall image from ClockDoc to whet the viewer's appetite.
The copyright for the image remains with the author and ClockDoc.
The image here has been reduced in both size and contrast in PhotoFiltre to maximize the detail in a smaller format.

Visit the ClockDoc Electric Clock Archives for some excellent closeups of this quite early mechanism. Enlargements of each image are available if you click on the magnifying glass above the images on ClockDoc.

http://www.electricclockarchive.org/ClockGallery.aspx?aid=2306

The many lacquered, brass/bronze parts are quite early in appearance. The contact assembly support post has a fixed, oval base plate. Only seen on early movements. Later WT movements have a taller base plate with slots for lateral contact adjustment. The masking pawl is of an early shape. As are the cast, brass contact steady bars with sharp angles. The coils of the power electromagnets are simply wound cotton or silk covered. Another early sign. Later coils had varying degrees of overall protection which his the individual strands of the windings.

Black paint on the mainframe and pendulum rod is usually an early sign but one can never be certain if it is original. This colour should not be taken as the sole indicator of an early movement. Though the sheer effort involved in stripping a later WT movement down just to paint every nook and cranny black will usually give the game away. One would never expect to see [later] plated parts on an original, black painted, WT movement.

Dismantling the massive power electromagnets from the cast main frame is fraught with very real danger of damage to the fragile coil leads. If a coil tail should be broken accidentally it could easily lead to a complete rewind of the coil! A very difficult task indeed and it is almost impossible to duplicate the coil's original appearance. It might be worth checking the paint below the coils as these do not allow easy access for a paint brush. The underside of the feet of the cast main frame might also show up any colour changes over the life of the movement.

The master clock in the same system is dated October 1925. So this WT may well be of a similar date. Though it should be remembered that Gents may have updated certain features over the lifetime of the clock under routine maintenance. The protective, galvanized steel enclosure may account for the fine condition of this movement. This C40B Waiting Train movement may have been working almost continuously for nearly 90 years. A tribute to the remarkable skills in design and manufacture by Gents.

The Gents WT was both a unique and a remarkably successful turret clock design. It's availability made the familiar weight-driven clocks completely obsolete. Requiring no winding and little in the way of maintenance, the WT kept time as accurately as its controlling master clock. Which usually meant mere seconds per month. Rather than the minutes per day variations of older, weight-driven movements. Many of which would lose time badly, or even stop, in a storm or icy conditions. The WT answered the need for far more accurate public clocks to match the modern requirements of the railways, commerce and industry right around the world.

The WT design also allowed very much larger dials at much lower expense than purely mechanical clock movements. Quickly setting a race in progress to achieve new records in huge dials quite incapable of being driven by weights. It also ensured matching accuracy for each dial in any clock system. Removing the need for the vertical weight shafts and access no longer important to the clock movement's winding and care made architects' lives very much easier. The compact size of a WT movement allowed towers, chimneys, war memorials and other architectural features to be fitted with large clock dials. Often in situations which would have been all but impossible with the older, mechanical movements.

Click on any image for an enlargement-
*

No comments: