skyeriding
901
Thank you patrickh,
I think it is based on design and tolerance. Typically you would see standard chronographs with 6 or 8 pillars; I'd argue that having 8 pillars requires finer tolerance as the column wheel only rotates 22.5° vs 30° for 6 pillars. So the pillars for the same diameter column wheel has to be finished finer to tolerate this together with the levers that are coordinated by it.
Additionally, mechanically the lever arrangement for turning the column wheel would benefit from the less rotational travel required, which I reckon results in a softer pusher (due to less force required to develop the same torque) or less travel distance required.
Monopushers are not to be shunned and require even tighter tolerance, as one pillar results in three rotational states. Therefore monopushers are usually built with less pillars to cope with precision. E.g. a high-end monopusher column wheel with "only" five pillars would rotate 24° per push (like in the MontBlanc Minerva ones). Note that I think it is more difficult to finish an odd-numbered pillar column wheel, as five pillars means each pillar has to be finished meticulously by itself while having an even number like 6 or 8 allows alignment to be compared with opposing pillars (you can run a file across the entire column wheel gap, etc.)
Regards,
skyeriding
How Column-Wheel Chronographs work (notably, the Lange L951 movements)
Disclaimer: I am not a watchmaker. The following is an unprofessional, hobbyist, technical(in-depth?) essay including pictures of how a chronograph movement works – based on my own view/understanding and tidbits of info I've gathered/read from here and th...
Brilliant! Simply brilliant!
What a generous and wonderful contribution to the forum. I've done several searches on this topic and have not found an essay as thorough and clear as yours. I cheated on the pop quiz. I didn't think Omega ever made a monopusher so guessed based on the en...
Thanks aardvarkbark,
I overlooked the Omega engraving on the bridge haha. A cam would look like this , in a 7750. [1] would be the cam itself, with all the levers actuated by it. [4] and [5] would be the reset levers and hammers, 6 would be the chrono bridge that couples and ...
Great write-up!
You've hit all the main operations - starting, stoping and reset - in one comprehensive post. Very much appreciated. That Lange is a beautiful movement too! You may wish to dissect the oscillating pinion and vertical coupling in a future post - the materi...
Thank you jmpTT,
I'd like to, however my knowledge on cam-chronographs are more limited. From my understanding, typically they are two levels and are shaped as to control the levers like the column wheel. Except, the cam rocks back and forth via the push of the chrono but...
I wanted to thank you for your wonderful write up and the time invested in creating this article.
I wish you the best of luck in finding a 1815 chronograph or datograph to fulfill your dreams. Best, Cholack
Monumental!
Thank you Skyeriding, the best Christmas present for someone, like me, who finds the chronograph complication the most fascinating complication in the horological world of mechanical mouvements. Yours is the best technical review on the subject I have had...
I'm gratified to hear that Francois, thank you!
Have a Merry Christmas and Happy New Year. Regards, skyeriding
What a GREAT presentation. May I ask you a novice question?
Why some columm wheels have 6 columms and others have 8 columms? Many thanks for explanations and avantages of a higher number of columms, if any. A great review to be read many times to expect acquire more knowledge on these beautiful chronographs. Best ...
Thank you patrickh,
I think it is based on design and tolerance. Typically you would see standard chronographs with 6 or 8 pillars; I'd argue that having 8 pillars requires finer tolerance as the column wheel only rotates 22.5° vs 30° for 6 pillars. So the pillars for the sa...
Very appreciated answers.
Huge congratulations skyeriding. I will have a closer look to my chronographs with 2 pushers (8 columns) vs monopusher (4 columns for the Longines 180th Anniversary (simple re-edition) ;-)) Best regards, Patrickh
Thanks for the great explanation, coupled with the illustrations.
It was very informative. I find the flyback mechanism especially nifty. Will you be tackling rattrapante chronos? Please do. And I wish you success in your Lange chrono quest.
Thanks Ruffian,
I actually did posted a write-up before on rattrapantes, but isn't too well written.. I may edit it and post it here in the future when I have time. Meanwhile, here are some extract images from it: Regards, skyeriding ...
You deserve at least half the watch for this post alone ;)
All I can say is thank you so much for making a lot of the mystery behind how a chrono works understandable to non-engineers like me And for making the effort in explaining it bit by bit, on a practical example, with pictures. Short of using Lego (which i...
Thank you KMII,
The clearest way I can think of is via video, but that isn't helpful as I don't know how to animate or I don't have a working 3d model of it.. I'll be patient with getting one. Acquiring such a watch would be a long term dream for me; having such a goal w...
You will cherish it all the more for the wait! :)
And your description was peerless even without a video - thanks!
what a great and informative post...even I can't follow all of it (!) learned a great deal
thanks for taking the time on this...
Amazing!
Thank you for sharing! It’s well written and the illustrations are so helpful. I appreciate you shining a light on the movement! Cheers!