Sooner or later it seems that most hobby machinists have to fulfill a need to build a clock. Not because they need one, but because need to satisfy the desire to prove to themselves that they can do it.
Over the years I had accumulated numerous plans that were available, but somehow I do not get much satisfaction from building something from someone else's plan, I'd rather do my own thing. That is not saying that I do not glean ideas from others, because I do that a lot, and sometimes modify them to fit my own needs.
For the clock, I finally went to the library and got a book on old clocks. I picked a small one with a picture that showed a good representation of the working parts and went from there.
There was no way of telling what size it was so I just guessed. It was pretty easy to estimate how many teeth in the gears, etc. so it was not all that difficult to make a scale drawing. According to the book the clock was built about 500 years ago, and perhaps that is before they had invented screws, because there are none in it. Everything is either riveted or fastened with tapered pins. At first I thought "how awkward", but it turned out to be every bit as easy as using screws.
There are a few changes in the design of my clock and the original. Mine has a little dragon rather than a bird to support the foliot or balance that controls the speed, which hangs by a thread. It keeps fairly accurate time, except it is different that modern clocks. There is only one hand, that takes two hours to make a revolution. My only guess is that 500 years ago they were still using hour glasses, and perhaps they had not standardized on the 12 hour dial as we now know.
Anyway it turned out to be a very satisfying project.