Brocot adjuster?

[bangster]

Is there any general rule-of-thumb for the amount of rate adjustment that comes with a full turn of the Brocot adjuster in your average shelf/mantel clock? A minute a day? A minute a week? Or no general rule at all.

bangster

[Scottie-TX]

"BROCOT ADJUSTMENT"? Wow, BONG!
You gone high brow on us now. SHEESH!

[leeinv66]

I can't answer your question bangster, but I can say that none I have had ever adjust the same amount per turn. In fact, I fit an adjustable pendulum bob to the American mantel clocks I have that are fitted with Brocot adjuster. I find them very poor at making fine adjustments. Or maybe it's just me who is poor at using them:bang:

[jmclaugh]

I have never seen a general rule of thumb but they are for fine adjustment so unlikely to correct one that is running a minute a day out. I suspect the only way to find out is to to test it.

[Ralph B]

If they were to be consistant, on French clocks anyway, each adjuster would need to be different for each of the many different pendulum lengths found.

This could be the case, I haven't looked too closely.
I'd be surprised though.

Ralph B.

[bangster]

Yeah, I figured that just MAYBE there'd be a rule of thumb, since most American clocks that havum have a pendulum length around 5". But I didn't hold out much hope.

bangster