Did you know that the American Numismatic Association (ANA) Money Museum in Colorado Springs, Colorado has a “Mini-Mint” in the basement? Here are a couple of short videos, one an introduction to the mint, and one specifically about edge lettering, using the upsetting mill / Castaing machine, similar to what was used for some Conder tokens!
According to Jeff Rock, “Many Conder token collectors have wondered how most of the edge lettering or design was added to the tokens. Most tokens actually had the edge added to blank planchets, before they were struck, using a Castaing machine (Matthew Boulton’s later token issues would be the first to use a segmented collar that could add a lettered edge as the token was being struck). The second video below shows the type of machine that would have been used in the 1780s and 1790s, operated by hand – and it is easy to see how error edges could occur.”