Confusions set in!! pendulum length and AutoTrain

[ArtF]

Hi Mark:

>>Incidentally I'd designed the clock around the 'ratchet' making two full revolutions every minute. This is just a good number for an added ratchet I'm going to add at another point. So In my mind the escape wheel will move two teeth every second?

  So the ratchet must make 2 revolutions per minute, or 1 revolution every 30 seconds. It has 30 teeth, so
it means for the proper pendulum it has to make 1 tooth go by every second. On an escapement as your using,
each full period of the pendulum makes 1 tooth go by.
  Theres a button on the indicators tab for calculating pendulum length, its a formula based on gravity
and it basically states that for small angular motions of less than 3 degrees or so each way, a pendulum
will obey the formula of  Time  = 2 * PI * sqrt( length / gravity); so since your clock was designed for
a 1 second pendulum time, ( 2 rotations per minute), a length of about 250mm would work.

2 * 3.1415926 * sqrt( 250 / 9600) = 1.01 seconds..

  Now..the calcs from the clock makers worksheet may depend on definitions used for whats first wheel, second pinion etc.. or on a particular type of escapement... I haven't used it before, but unless your using a train that corresponds
to their definition of the wheels you could get weird results.  It looks good to me at 250mm's or so for
pendulum length.. In gearotic, you design exactly as you did, knowing how many seconds you need for each pendulum
period, and then just look to the formula for pendulum length.. or..better yet, decide on the height you want
your clock to be, figure out how much of that is pendulum, calculate the time from that, and design the mechanics accordingly.. so it looks to be that you've done fine..

Art

[mphil]

Art thank you very much for the effort you've put in for me. It is a leaning curve but one made far easier due to Gearotic so thanks for this also. Along with my 3D printer I will be prototyping my design and I've already tested some wheels with good results.

Mark ;D

[ArtF]

Mark:

No trouble. I find 3d printing gears works real well, Its my preferred method of making something
next to wood. Have fun, show us the clock when its done. :)

Art