How To: Custom Sprocket
We’ve discussed how to renew old sprockets by adding new teeth (second article here). And shown some information from the 1917 Reynolds chain company. But this article is about how to make a very special customized sprocket.
Here is an advertisement from the Edward Williams company circa 1922. They supplied sprockets and crank arms for bicycles and motorbicycles, with custom patterns. BSA and others had their names or symbols cut into the steel chainrings.
The 1913 Veloce project bike needed a chainring, so I thought that I’d create an interesting one to fit it. Using Solidworks, I drew a solid sprocket and then cut each letter to match the old lettering on the Velo gas/petrol tanks.
The next step was to buy a sprocket from Martin Sprockets and Gears, via the local bearing shop. I bought a special wide sprocket, then cut it on the lathe to have a dished section to match the old sprockets.
Sending the .DXF drawing to a friend who has a water jet machine, and hey presto! There was a sprocket in my mailbox the next week.
After polishing and plating, I fitted the crank arms and pedals. Now the assembly is ready for the rest of the bike to be finished…