This is my first animation. I used the mesh gears in an add-on by Michel J. Anders. It runs from blender file had to tweak the start and stop points. Five to one reduction. I am thinking of making a 3d clock using the same idea. Here is a jpeg of the gears.
Here is the blend file 522k:
gears-in-motion.blend (522 KB)
Enjoy Joe.
looks good!
a clock would be cool - there has been at least one clock mechanism done in blender before
it looks like your angular speed is not constant?
instead of a clock you could always consider going a bit more elaborate? an orrery perhaps (though the work involved will keep you very busy for some time :P)
@bacon_chaney: "instead of a clock you could always consider going a bit more elaborate? an orrery perhaps (though the work involved will keep you very busy for some time :P) "
An orrery! That would be awesome. To kick it up a notch may I suggest the antikythera mechanism?
today we learn the name of various rare and complicated mechanical devices 
i fear we will make joe tired before he even starts on his clock …
Steeve, I wondered if it would be that noticeable. Clocks run so slow that I will be able to overcome the angular start up. I tweaked it for a while trying to get the sync of the two independent rotations. Got to do a little more math. Not my best field. Thanks for the feed back. Joe
bacon-chaney, Do you mean a ( mechanical device that illustrates the relative positions and motions of the planets and moons in the solar system). Thanks for the input, I am very new at this blender, but it has me hooked. Joe
joe, only some people would notice…as you say though, maybe not at the rotation speeds of clock gears
there must be a way to set the rotation speeds precisely and also to link the speed of one to the speed of another
i’ll look into it
i may be able to help with the math …
yes 
its called an orrery though im not sure whether i have spelt it correctly now lol. my stepmum built one and its an impressive piece of engineering. i would be tempted but i think i would get frustrated working out the math of it all.
joe, here is a modification of your blend file.
i wanted to figure out pydrivers in 2.5 and this was the perfect project
basically, instead of using keyframes and curves to control the animation, this method uses a pydriver which is just a line of python code
in this example, the z rotation angle of the small gear is linked to the frame number.
so as the animation clicks to the next frame, the gear rotates by a set amount.
the z rotation angle of the large gear is simply set to one fifth of that of the small gear.
the beauty of it is that by slowing down the small gear, the large gear automatically slows down. nice.
also an animation here: http://vimeo.com/22182216
gears-in-motion-pydrivers.blend (523 KB)
in “Dark Crystal” - the big planet moving machine in the old lady’s observatory was an orrey I think.
…sorry just thought of that.
thx for post …interesting
Thanks steeve, :eek: Now you got me! I played around with your modified version it really works good. Now I am going to have to learn python code.
Question - what does blender have to control the period of a pendulum. I was reading about harmonic force would that work for me? Anyway, thanks again for your input. Joe
on second thoughts, a steady angular speed for the gears is not appropriate for a clock, where the gears basically stop and start constantly under the control of the pendulum (if it has one) and the escape mechanism.
so you are right, the movement should be simple harmonic motion. not difficult to arrange with python - i’ll give it some thought
don’t be too worried about learning python - pydrivers just use one line of code at a time. Once you have the code, it should just be a matter of tweaking a few parameters for fine tuning
I added some more gears and a shaft to the project. Got the shaft mated with the centre gear, but can’t get the pydriver to work on my 96 tooth ring gear. Here is a pic of the latest.
Here is the updated blend file it is growing 945.1kb :gears-in-motion-pydriver+ring6.blend (945 KB)
Joe.
May I ask exactly how you animated them, or by hand?
JOE1, advance the technology of Blender 2.5 by duplicating this clock gear set:
okchoir, link missing?
The embedded video is visible in my browser (Firefox), so I don’t know what is the problem for you. Here’s another link:
http://www.vimeo.com/5241728
Joe, to apply a pydriver:
make sure the animation as at frame zero
select the 96 tooth gear in 3d view
N to get the properties panel
mouse over Rotation > Z (should be 0 degrees)
RMB and choose “Add Single Driver”
In the Graph editor window, Drivers View, select Z Euler Rotation (Gear.004) (list on far left)
N to get properties pane
under Drivers write / paste the pyhon expression into the Expr field
in this case:
bpy.data.objects[“Gear.001”].rotation_euler.z / 8
so that the 96 tooth gear turns 8 times slower and in the same direction to the small gear
then for some reason i am not sure of, under Add Variable,
LMB in the field next to Object and select Gear.001
then the animation should work
you may need to tweak the starting rotation of the large gear so that it meshes nicely with the smaller ones