Learn
- Essential Clock Repair Tips
- Clock Repair Guide
- Questionable Practices
- Wheel Tooth Repair
- Wooden Tooth Repair
- Escape Lever Restoration
1
A cherry wood wheel from an 1825 Seth Thomas clock with a broken tooth.
The first step of restoration is shown; cutting along the lines that denote the new tooth root.
2
The root is partially cut.
3
The root cut is complete.
4
A new piece of cherry wood, with a thickness that matches the original cherry wheel, is rough-cut. Notice that the wood grain is oriented to be along the length of the tooth and not across it, for stability under load.
5
The new tooth, left large intentionally, is dry-fit to the root. Some minor final root shaping is still needed in this view.
6
The new tooth is glued in place with TiteBond carpenter’s glue. Given the thick cross-section and large gluing surface area, there is no need to keystone-shape the root. The repair will be perfectly stable.
7
A paper template is prepared by tracing along the edges of a good original section of teeth. Note the bevel on the 0.5 graphite pencil tip, to increase the accuracy of the template by enabling drawing right to the wood edge.
8
The template is cut along the pencil line with an X-Acto knife.
9
The cut template is separated from the parent paper.
10
The template is accurately positioned on the wheel surface by aligning to neighboring teeth, in order to reveal how much wood must be trimmed from the exposed portion of the new tooth. A fine guide-line gets drawn against the paper.
11
After repeating the template-positioned, fine guide-line pencil line on the opposite side of the wheel, the excess cherry hardwood can be removed with a file. This is repeated until the pencil lines from the template are met.
11
After repeating the template-positioned, fine guide-line pencil line on the opposite side of the wheel, the excess cherry hardwood can be removed with a file. This is repeated until the pencil lines from the template are met.
12
The wood removal procedure is carried out more slowly as the pencil line nears the file. The tooth begins to take on the unique, slightly slanted shape that gives some added leverage to wooden wheel teeth.
13
Shown now from the other side, after careful filing of the tooth tip to match the height of it neighbors, the wheel is rolled along the straightedge of a rigid file in order to test the height of the new tooth. The bumps should all feel the same.
14
After some careful finishing of the tip and coloring, which contributes to the surface strength and wear-resistance of the new tooth, the repaired cherry wheel is ready to continue giving service as the clock approaches two centuries of age.