To ensure stability, the RAS regulator was designed for permanent placement within a wall recess where it would be isolated from the normal vibrations of a floor mounting.

My regulator backplate is a large alloy plate 10mm thick and braced on the rear with steel angle strips to ensure no bending of the plate.

 

The two brackets that support the mechanism are aluminium castings, bolted on from the rear.

 

In my workshop, the plate is fixed with 200mm stainless fixings into a three-hundred year old massive stone chimney breast. This is as good a seismic block as one could wish for.

 

The pendulum suspension assembly is a massive construction and incorporates the provision to alter the cheek radius contact with the suspension spring. The radius affects the length of contact with the suspension spring, altering the effective length of the pendulum, which enables compensation of circular error.

 

As the circular error characteristic can only be ascertained when the clock is working, I opted for a method using rolled cheeks for initial assembly. These can be re-made to a different radius to achieve ultimate performance. The test cheeks are rolled to a precise radius and are steadied in position with adjustable supporting blocks. Eventually, the rolled cheek radius can be machined on the solid support suspension cheeks.

 

The suspension bracket has two columns which brace the top of the mechanism to ensure a rigid construction.