Verge and Foliot Escapement Adjustment on Horologium

Horologium by Joe Coser

Joe Coser writes:

 

Good morning Clayton,

Attached is a picture of the Horologium I just finished. Thank you for the excellent plans and directions.  I am working on the time it runs fast. I have reduced the weight to 5#--I think I will try reducing it more before making the alternate wheel.

Thanks.

 

Very nice work, Joe. Your Horologium is a beauty. Each part of your clock is so crisp, and clean, and well made. Your excellent craftsmanship shows throughout your build.

 

You are correct about decreasing the drive weight if your Horologium is running too fast. Many of my clocks have escapements that are not very sensitive to how much drive weight is applied and a little excess drive weight is not a problem. That is not the case with the verge and foliot escapement of the Horologium. V&F escapements are very sensitive to changes in drive weight, and as an aside that is why, instead of using a standard clock mainspring, I went with a constant force spring in the Wee Willie. A verge and foliot escapement requires that the drive force applied to it be constant.

 

As you probably read in the instructions for the Horologium, there are three ways to change the speed at which this type of escapement runs; 1) vary the drive weight, 2) open or close the "wings" of the foliot, or 3) change the number of pins on the escape wheel. Actually, there is also a fourth method and that is to add more weight further out on the pendulum's shaft. In other words make a wider or heavier foliot. That could be by adding additional weight in the wings themselves or a separate foliot addition down by the sphere you have put on the bottom of your pendulum's shaft (actually, adding weight further out anywhere along the shaft would work.). You can see how John Hilgenberg did just that by checking out the picture of his Horologium in my Flickr' link.

 

Thanks for sending the picture so we could all see the great work you put into building your Horologium.

 

Enjoy.

 

Aloha. Clayton