Sherline Horological Milling Machine Bushing and Depthing Accessory 2118
When a non-jeweled clock or watch arbor pivot rotates for many years, it will, in many cases, wear a path in the movement plate in the direction of force.
When this happens, the pinions and wheel teeth no longer properly mesh without adding friction, which, in turn, prevents the movement from functioning properly. To correct this, a hole is reamed in the original location and a bushing is installed in that location, returning the hole to its original size and position.
When starting out, most repair people will use a hand set of either KWM or Bergeon reamers and matching bushing assortment. When using hand methods, the common suggested method is to first file an equal length path opposite side of the wear. This is done in hope that the reamer will center itself in the original location by following the path of least resistance. Some days you’re lucky, some days you’re not. This method gets old fast if any number of bushings are done.
The Sherline Horological Milling Machine
The Sherline mill offers more precise bushing installation for both clocks and watches. Additionally, it will perform depthing in the same timely fashion for about the same cost as a bushing machine. Current bushing machine prices range from about $800 up to $1,200. A milling machine offers added capabilities for any repair as well as the construction of a movement from bar stock.
What You Need to Bush on a Sherline Mill
- We recommend a 5000 mill with a headstock spacer or 5400 mill. You will need a spacer to fit plates up to 7″ wide that cover most commonly encountered movements. A second spacer could be added if ever required.
NOTE: We recommend using our 5400 mill over our 2000 mill for bushing. The 5400 model has a fixed column and it is less likely to move when you use the headstock as a bushing press. Customers purchasing a mill for bushing should first read the instruction and assembly guide. It will help to become familiar with the operations of the mill.
- A Horological Bushing and Depthing Block set.
- Reamers and matching bushings of customer’s choice
The idea for this accessory was given to Sherline by Jerry Kieffer who is a long time Sherline user. He also was a Craftsman of the Year. The basic concept of this accessory is to use a small milling machine to do the job of several specialized clock and watch repair machines. With the Sherline mill you can maneuver and align your clock and watch parts easily and accurately.
You can also machine your parts more accurately in regards to the size and location of your bushing hole. Afterward, you can use your milling machine as a manual press. Use it to insert your bushing. This accessory also makes depthing easier and more precise, allowing you to locate your gear exactly where you want it.
You can also check the gear mesh with the mating gear and then machine your bushing hole exactly where you want it to be. By using the Horological Bushing and Depthing Accessory in conjunction with your Sherline mill, you now have a three-in-one clock and watch repair machine that is also a fully functional milling machine.