Pretty cool stuff.
Hope this type of animated picture is of some use to you if you are trying to build your own clock.
Double clicking on the thumbnails below will lead to other webpages with more animations, jpegs and pdf files to help you understand some of the theory behind clocks.
Beware. You might just find as many questions as answers in the links below.
For example there is very little information out there on just how heavy the bob should be on the pendulum.
Or just how long can I expect my clock to run in between windings?
Why are the gears as big as they are? Are they too big?
What about other escapement designs?
Heard that cycloidal gear teeth are better than involute for clocks. What on earth is cycloidal?
For some of the answers and even more questions double click away.
Reality Check. Read this first.
There's some pretty good info on this page.
But to be totally honest, it is a little bit of an overkill.
Many of you might read on and become intimidated about building your own clock.
As in ,"Man I could never do this!"
Remember earlier I said that my kids helped me with a lot of the work. If they can do it, You can too!
Somehow I got sidetracked by all of the fascinating questions from you guys and dusted off my old textbooks. Wish I'd paid more attention in school.
So I set out on a quest and it got a little weird.
lot's of questions. some answers
It is not my intention to repeat information that is easily available from other places on the web or from dusty old textbooks.
It got so weird that at one time I started to explain how teeter-totters work on this page.
Not so weird after all. If you understand teeter-totters you have a real leg up on getting the gist behind mechanical engineering.
back to the questions
Wooden clock making is a lost art. But judging from pictures on the internet it's making a comeback.
Wooden clock making was supposedly very popular at one time. Millions made. Yet has anyone ever seen a photo of an old antique woodenclock?
Say over 200 years old? Even 100?
Please send me picture if you do.
A clock is a simple machine. There is plenty of information available to help with the construction of heavy machinery but little for us clock makers.
Plenty of info and tables about involute gearing can be found in
The Machinists Handbook. Not much anywhere on cycloidal tooth forms.
Even the formulas for involute gearing from The Machinists Handbook don't seem to work when you start using wheels with more than 60 teeth.
Here is a good link on how to draw cycloidal gears.
Early on I forgot that some poor guy (this includes girls) was going to have to try and cut gears using a scroll saw.
There is a big disconnect between what you can draw on CAD (in my case Solidworks) and what you can cut by hand.
Don't forget our friend Mr. Sandpaper is bound to raise his head at some point in the game.
It was real easy to get all caught up in finding the ultimate gear tooth especially when you get glued to the computer screen.
There are clocks that use triangular tooth wheels that drive pinions with wooden dowels for teeth. They work just fine.
So read on but remember it's just a woodenclock after all.
Make it and break it
The math and theory are nice but shouldn't scare anyone away.
I'm a big fan of building simple prototypes to test out concepts.
Some of the pendulum questions can be answered in minutes by suspending a yardstick from a nail.
Keep it simple. Enjoy.................................................................
Tolerance Analysis on a pair of gears
A comparison of involute and cycloidal gear forms.
A look at some cycloidal gears