Out & About November 2017

OA feature

The VERGE-AND-FOLIOT was the most common mechanism for controlling the descent of a weight in a weight-driven clock. The ESCAPEMENT is the mechanism that controls the transfer of energy from the power source to the counting mechanism. The FOLIOT is the earliest form of mechanical-clock escapement consisting of a crossbar with adjustable weights for regulating the rate of oscillation of a verge or vertical spindle. ACCOYA is a modified timber that has properties that match or exceed those of the best tropical hardwoods and treated woods, yet is manufactured using wood from sustainable sources.

Description of work carried out on the cable drum The drum has clearly been replaced at some time in the past as the original drum would have been made of a suitable hard wood. The method used for the conversion was somewhat crude, the original blacksmiths-made shaft with its integral ratchet has been cut short and used as the back bearing journal, where the shaft sits. This would have been acceptable other than the shaft diameter was a poor fit in the drum, creating massive wear in the wooden drum. I have turned the shaft and fitted a flanged bush in the wooden drum. The front bearing had a steel bush welded to the frame plate to compensate the thrusts from the winding ratchet. Using a steel bearing running on a steel shaft is not good practice, hence the bush had worn considerably. It was discovered that the replacement winding drum is not as wide as the original, and to overcome this, a previous repairer had added a steel spacer, plus a piece of bent rod to fill the gap. I have manufactured a phosphor bronze bush with a flange on the side to manage the thrust from the winding ratchet and also turned a new steel spacer the same length as the previous one.

Back bearing of the winding drum being turned to remove wear.

The original shaft now skimmed / polished, with new phosphor bronze bush bolted in place.

The winding drum before restoration.

New winding end assembly.

Original ratchet here.

Replacement ratchet.

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