Repairing A Chipped WW Lathe Pulley

Copyright 2008 by James P. Riser



Chipped pulleys are a common problem on watchmaker lathes and countershafts found on the used market. I ran across a lathe, countershaft, motor, bench and assorted watchmaker/clockmaker items at an antique shop and thought I would add the items to my arsenal of machines. The cone pulley on the countershaft had two chips on it. On this web page I shall show how I repaired these chips in the hopes that the info will help others.

Step one was to clip the head off of a straight pin.


This pin was then inserted into a pin vise to hold it securely.


The idea I had in mind to repair the chips was to create a type of fiber filler for the chips.

I have a large quantity of the polyester cording shown here to use in certain items that I manufacture. This cording was to be the fiber filler and was to prodide the strength for the repairs to the chips.

Super glue was to be the resin to hold everything together much like fiberglass.

The cut off pin was to assist in placing small strips of the cording into position and to keep my fingers out of the super glue.



Below are shown three steps in filling the chips with the cording. The cording was placed into position then a drop or two of super glue was applied. The pin held the cording strip in position until the super glue set up. I added as many layers of the cording/super glue as needed to fill up the space within the two chips. The right hand image shows how things looked when I felt the chips were filled.



A Dremel tool with the bit shown here was used to roughly trim away the extra cording.


This is how the pulley looked after the rough trimming.


The trimmed patches became "fuzzy" during this trimming and more super glue was applied to bind everything together.


I then mounted the countershaft on my Sheldon lathe to clean up the repair job.

The "V" groove was machined to match the others on the pulley.

And the end of the pulley was also cleaned up.

During the process, the repairs got "fuzzy" again. More super glue was applied to bind any loose fiber edges.




The repaired pulley now looks like this and is once again a very useable pulley.






The repairs are visible due to differences in color. A little leather dye could be used to hide the color differences; but I am more concerned with the nice countershaft being a working part of the lathe drive system.