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Wow, I guess I should know better than to try to write a post too close to bed time.

Chuck,
Thanks for the kind words, while I do have some skills I hesitate to claim the title "expert". I still have much to learn.

Thanks to JPG for expressing my thoughts more clearly.

I was becoming concerned that with all the talk of laser cutting and CNC that others would get the impression that these things are necessary to produce a good clock. They aren't. With a couple of jigs or fixtures anyone on this list can produce a clock movement capable of keeping time as well as the brass movements available in the catalogs.

As JPG observed time keeping is more a function of escapement type and factors influencing the period of the pendulum.

Paul, the novelty clock you are referring to has a verge and foliot escapement that is inherently a terrible timekeeper.

There are a great many modern designs out there, I looked into a few some years ago. Most were all form and no function. Basically very decorative but not designed by anyone with much horological knowledge. I won't argue about the pros and cons of involute, cycloid, or even triangular tooth shape. Instead I suggest looking at the bottom line. How efficient a machine is the clock.

For example I have a few running shelf (mantle) clocks all circa 1830.

An 8 day that runs on a 9lb weight with a 23" double fall

a few 30 hour clocks:
3 1/2lb 26" single fall
3lb 15" double fall
5lb 22" single fall

Ask any 10 horologists a question and get a dozen different, fiercely defended answers. My opinion, any device that requires you to wind it two or three times a day is kinetic art, to be run for visitors or on special occasions, not a practical timepiece. For me even the 30 hour clocks are only worth winding on the weekends when I get some shop time. The movement shown in my avatar is an exception of sorts, a clever design that uses only one weight to drive the time and strike trains. The owners of this long time family clock don't mind winding it twice a day.

Troy

horologist wrote:Wow, I guess I should know better than to try to write a post too close to bed time.
Troy

I think the "too tired to think straight and behave in polite company" award goes to me. I mis-read one line of a good post while wiggling in my chair with heavy eyelids and a full bladder, and took it out on the forum.

I suspect that the hundred-plus year old clocks I saw in Germany were either set by sunrise and an almanac, or when the bells from the city clock could be heard, and were only for special occasions that couldn't be missed, like church or a hanging. (Though there was always somebody who would have rather slept late and missed the hanging.)

There is an ebook about making a "medieval wooden clock" with standard tools -- it is available here: http://thescholarsgarret.com/clock/
I bought it and would have a very hard time recommending it unless you had zero idea where to start. The clock described is nearly identical to the plans available for free here: http://www.woodenclocks.co.uk/Clock4.pdf

The differences are largely cosmetic, with the exception of a slightly different Verge and Foliot layout. What the book is good for is describing a set of jigs that can be reused to make the clock described, and variations. Because it is "Medieval" clocks, Verge and Foliot is the only escapement described.

I am semi-curious about the Verge and Foliot "double-escapement" clock here: http://www.clockplans.com/PAGE26.htm
I doubt I'd buy the kit because when assembled it almost looks like it was made from cardboard. What is more interesting is the claim that the clock is "extremely accurate." I wrote to a fellow who has built quite a few wooden clocks and he said it was indeed accurate, but I am still skeptical. (by nature)

Paul,

These clocks are all loosely based on the design used for the "Columbus Clock" these clocks were sold during the Columbian Exposition in Chicago and for a number of years following. This clock was also reproduced in the 1970's.

[ATTACH]9044[/ATTACH]

Over the years there have been many variations all based on this design. I have one and to my shame passed on an impressive 3 foot tall version.

They are novelty clocks that bear only a passing resemblance to the 15th century iron clocks they are said to copy. Great fun but terrible time keepers. The verge and foilio is inherently an innacurate escapement and you are quite right to be suspicious of any claims in accuracy.

Troy