Today I completed the clock's regulator. What it needed was an adjustment knob made, and threads cut on the foot shaft. Before finishing the regulator, I ran the clock for a while, getting it close to keeping time by sliding the foot up or down in the regulator block. This helped to determine the approximate final position of the finished regulator foot.

The regulator foot has a 3/32" drill rod shaft. I use drill rod, even when I'm not going to harden it, as in this case, because it's sized much more accurately than common stock. The 3/32" size is quite close to a metric 2.5 mm size, and I chose to cut 2.5 mm threads because they're quite fine and appropriate for a regulator, which should move only a little when the nob is turned, for accurate adjustment.

I made the knob from 1/2" brass. I used metal stamping punches to stamp an "F" for Faster and an "S" for slower on the top of the knob. If you turn the knob towards the "F", the regulator foot screws down, shortening the effective length of the suspension spring and increasing the clock's rate. Turning the knob toward "S" raises the foot to effectively lengthen the suspension spring, retarding the clock's rate. Only a portion of the regulator knob tube is threaded.

To make sure that the foot descends when the knob is turned to make the clock run faster, I installed a compression spring between the foot and the bottom of the mounting block.

Springs are easy to make. This one is made from .010" music wire. I taped an end of a piece of wire to a 3/32" mandrel, put the mandrel in the little lathe and ran it at its slowest speed, thus wrapping the wire on the mandrel. The wire must be kept in tension to make it bend around the mandrel.

When the spring was wound, I stretched it out and cut out a suitable piece to make the spring.

This regulator is delicate and finely made, and I'm proud of it.

I also made a device which secures the balance when the clock is being transported. It screws on to the bottom of the motion limiting device -- that which replaced the bottom jeweled balance bearing. It has 1/4" fine threads which permit screwing it onto the limiting device and it is drilled with a smaller hole at the bottom which retains the bottom of the balance staff. The balance staff is secured with a thumb screw, which prevents the balance from turning and also from slipping upward. The device is screwed off when the clock is running.

Today's links:

Regulator knob
Spring wound on mandrel
Regulator spring
Regulator complete
Regulator installed
Balance clamp
Balance clamp installed