A bit of arithmetic shows that the only feasible number of leaves on the minute wheel pinion must be 8, giving a gear ratio between the minute wheel and the hour wheel of 8/33, again not a whole number. The gear ratio between cannon pinion and hour wheel then becomes 11/32, not a whole number. This gives a minute wheel overall diameter of 4.8mm. If the minute wheel's tooth pitch is the same as that of the hour wheel - which may or may not be a reasonable assumption, but from images I've studied they look to be the same - then the maximum number of teeth on the minute wheel can be no more than 32. I've done some more detailed measurements tonight, and the maximum diameter of the missing minute wheel can be no greater than 4.9mm in order for it to fit into the available space and mesh with the cannon pinion. I can understand what you're saying, and minute wheels are frequently larger than hour wheels, but in this case a 44-tooth minute wheel would simply not fit into the milled-out space available, as the attached photo hopefully shows. Some images are attached which will hopefully enable someone to identify it. As I type this, it’s ticking away happily. However I’d really love to repair it and use it again. Giles Watchmaker and Jeweller, Oswestry” on the winding key, and no hallmark is visible so I think the case is gold-plated. I can’t find a maker’s name, other than “H. A serial number 20479 is stamped inside the dome. I think this is probably a cheap mass-produced 19th Century watch. However the biggest surprise was when I removed the dial and discovered that the minute wheel is completely missing! With the movement out of the case, it runs but the balance swing is uneven and the movement is clearly in need of cleaning and lubrication. The watch has been looked at by a jeweller recently, and he reported that repair was “not economically viable” but I took that as a challenge! I bought a 1953 second edition copy of “Practical Watch Repairing” by Donald de Carle and have been doing some homework. I inherited this small gold-coloured (lady’s?) pocket watch from my late mother and I believe it originally belonged to her mother, who lived from 1878 to 1958. However I’m totally new to watches, so I wonder if I could ask for some initial advice here? I’m a relatively new NAWCC member and have been repairing clocks as a hobby for a few years.
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