Rephrasing the given text: Inquiring about the term 'bushing a clock' means asking for the explanation of that particular phrase.
In this first part of a two-part series, we delve into the world of antique clock maintenance, focusing on an often overlooked yet crucial aspect: pivot wear and bushing.
Our featured antique clock is a Mission style clock, crafted by the Sessions Clock Co. of America in the 1920s. With its classic Mission design, this clock is not only a timekeeper but also a piece of art, adding an elegant touch to any room.
Mechanical clocks, like our antique piece, rely on the smooth operation of numerous small parts. Pivots, the ends of axles (arbours) that spin in small holes drilled in the clock plates, play a significant role in this mechanism. However, over time and improper maintenance, these pivots can wear out, causing a variety of issues such as intermittent stopping or the clock not running at all.
A worn pivot or worn pivot hole causes the gear to move away from the pinion and eventually stop when the gears no longer mesh properly. This wear is often found in clocks that have been oiled excessively without proper cleaning.
To identify worn pivot holes, inspect the movement for pivots that exhibit excessive side play or wobble, visible ovalization, or irregular wear around the pivot holes. Common signs include noisy running, erratic timekeeping, and visible scoring or deformation inside the holes. A magnifying glass or jeweler’s loupe can help detect these issues.
Repairing worn pivot holes typically involves rebushing, a process that involves drilling out the damaged hole and inserting a new, precisely sized bushing (a small metal sleeve). The general steps are:
- Remove the movement from the clock and carefully disassemble it to access the worn pivot holes.
- Drill out the worn pivot holes using a correctly sized drill bit, ensuring the hole is true and centered.
- Insert a brass or steel bushing of appropriate size into the drilled hole. The bushing should have an inner diameter matching the original pivot size.
- Fix the bushing securely using clockmakers' glue or by peening in place.
- Ream or polish the bushing interior to achieve a smooth, correctly sized hole for the pivot.
- Polish the pivots themselves to ensure smooth operation and correct fit within the new bushings.
- Reassemble the clock and check for proper function.
Before rebushing, pivots are usually measured and polished to optimal dimensions to fit tightly in the new bushings and reduce wear.
This rebushing process is a standard clockmaker’s repair technique used to restore mechanical clocks with worn holes and extend their operational life.
In the next part of this series, we will discuss the importance of maintaining a clock's movement and the essential steps of clock movement servicing, as well as addressing situations where the pivot itself is worn or broken.
[1] Clock Repair Guide: Bushings and Pivot Hole Repair [2] The Horology Handbook: Clock Repair and Restoration [3] The Complete Clock and Watch Repair Manual [4] The Art of Clock Repair: A Practical Guide for Clockmakers [5] The Clock Repairman's Guide
This article was not researched specifically for this clock but was found in a thrift shop in Pembroke, Ontario for $10.
In the intricate world of antique clock maintenance, understanding the importance of vintage clocks' pivot wear and bushing is essential, especially when faced with smart-home devices replacing these gadgets of technology. Pivot bushings, small metal sleeves inserted to replace worn pivot holes, are a crucial aspect in maintaining the proper functioning of vintage clocks like our Mission style clock from Sessions Clock Co. of America. The repair process involves meticulous steps, from measuring and polishing pivots before rebushing to ensuring the smooth, correctly sized hole for the pivot after reaming or polishing the bushing interior.
