Questions concerning clocks

[Nick]

I've thought about making simple mechanical clocks for a while, and have spent a lot of time (no pun intended) researching late medieval and Renaissance clocks. I've got most of it figured out, but I've got two questions, one concerning the making, and one concerning the works.

My biggest problem in making a clock is the gears. How should I go about making the gears? I've got a couple ideas, but I'd like any input. I don't have easy access to a welder or a torch.

Second, to anyone with knowledge of old clocks, where would be a good place to look for information on the verge and foliot escapement? I've looked online, but not really found what I'm looking for. Are there any good books on the subject?

I've attached a couple pictures of the kind of clock I'm interested in making. Most clocks of this type are made of wood nowadays, but I really want to do it out of metal.

[Chris Pook]

Fun project...

Have always wanted to make a grandfather clock with that kind of mechanics.
Please post up any info you find.

[Sam Salvati]

The only way really is to hand file the gears in, or machine them on a lathe or something i would say. I watched this thing on the History channel about a guy that remade some old Davinci and other's inventions, ones with gears. So he cut out the discs with a compass, marked the depth for each tooth, and used a file to hand file in sharp point gear teeth.

[oakwoodforge]

Nick you need to get together with "Bomlin " he usually shows up for the weekly BP's and is sometimes in IFI chat, he has been working with primitive /medevil clocks for some time, Possibly you could pick his brain and you guys can compare notes.
hope this helps

Jens

[ThomasPowers]

May I also commend to your attention "Mechanic Exercises" by Joseph Moxon, published in 1703 and containing a section on making a clockwork spit turner that will give a lot of info on how it was done manually. (Astragal press reprinted it in "modern" times)

Thomas

[Sam Salvati]

Jeez Thomas, you are like a smithing library.

[Nick]

Well, I did manage to figure out the escapement. Thanks for the book title, Thomas, I'll have to try and find it.

My biggest problem now is making the gears.

[Nick]

Here's the sketches I've been working on. I think I've got everything worked out in rough form, now I need to get some graph paper and start making a more precise blueprint.

(Large picture!)

[Daryl]

First, you will have to get into your math and pretty much do the same as a machinist making any other type of gear.
Second, start by making a couple of larger gears (as in larger than what you would ever want to put in a clock), this will help you sort out in your mind how you will approach the project as it is scaled down. You have to deal with inner and outer diameters of the gear teeth. The shape (obviously) goes hand in hand with the escapement design. The ratios of the gears, in order to make the clock accurate, really simplify how many teeth will be on it. A simple start is to make the first set of gears with the intention of only using a minute hand.
These are your first two steps.