Mulligan No. 8: Graham’s interpretation of the Dent table regulator clock

Respected Australian clockmaker and horologist Graham Mulligan recently embarked on a journey of horological finesse to recreate his interpretation of the Dent table regulator clock.

After buying a set of three books titled ‘Precision Pendulum Clocks’ by Derek Roberts, my favourite books at the moment, I became keen to build something special and unique. The clocks I have built in the past have all been my own design. This time I wanted to build my interpretation of a clock built by Edward John Dent, that was part of a series of table regulator clocks that he built.

As written by Derek Roberts in his book ‘English Precision Pendulum Clocks’, “these were probably the most attractive clocks Dent ever made with their beautifully nished cases, nely engraved dials with seconds’ hand, fully exposed movements and half seconds’, mercury com- pensated pendulums with cast iron jar.

”Edward John Dent (1790-1853) was a famous English watch and clock maker, noted for his highly accurate clocks and marine chronometers. He founded the Dent company which is still a legacy of horological excellence to this day.

It is unlikely that more than ten originals still exist (dated circa 1840-1846). Limited information on these clocks is available on the internet; only three have been sold through auction in the last 15 years, ranging in price from US$60,000 to US$100,000. No technical information was available on the clock, so it was necessary for me to study the photos in the book and try to replicate the clock as best I could.

The starting point was to use a fusee movement I had spare.

Starting Point

The starting point was to use a fusee movement I had spare.
New plates were made and the train replanted.

Plates

New plates were made and the train replanted.
Initial construction stage of the ‘A Frame Bracket’ used to independently mount the pendulum. This type of design is commonly found on fine longcase regulators.

A-Frame Bracket

Initial construction stage of the ‘A-Frame Bracket’ used to independently mount the pendulum. This type of design is commonly found on fine longcase regulators.
The four columns are from solid brass bar stock

Four Column Design

The four columns are from solid brass bar stock (as pictured above in their original form).
Bar stock turned down on a lathe using a form tool to shape the top and bottom capitals.

Turning Columns

Bar stock turned down on a lathe using a form tool to shape the top and bottom capitals.

Base & Finished Columns

Finished columns, after shaping capitals on the lathe. Construction of clock base frame, to later have silvered brass panels inserted.
The original pendulums for these clocks were a cast iron jar with a threaded top and were mercury fillled.

Pendulum Construction

The original pendulums for these clocks were a cast iron jar with a threaded top and were mercury filled.
Finished pendulum

Finished Pendulum

Instead of working with all old methods and materials, I decided to construct my pendulum from stainless steel as opposed to cast iron.
Cutting the escapement wheel

Cutting The Escapement Wheel

With the pendulum made and the clock up to a height to allow it to swing, the next job was to get it to run. I knew the fusee gear train I had would not be right for timing. I also wanted a seconds dial. After cutting new wheels and pallets, the only remaining parts from the original fusee train was the barrel, fusee cone and centre wheel; all of these were altered slightly.
Testing Escapement Wheel

Testing Escapement Wheel

Testing the escapement wheel in the movement before crossing out.
Escapement Pallets

Escapement Pallets

Pictured above the escapement pallets is the beat regulator. This is used to easily set the clock into beat.
Dial

Dial

Now the clock was running and keeping good time, I focused on the dial and hands. The dial was designed in collaboration with myself, Tasmanian graphic artist Saige Dingemanse and my son Luke Mulligan. The design is based upon the original Dent regulator dials, including sourcing typefaces that were common on dials of that era and style. The process used on the dial was photo chemical etching and it was hand-silvered to finish.
Clock hands

Hands

The hands were cut from steel sheet and made to complement the original Dent style hands found on these clocks. The finish process to achieve the desired look was heat bluing.
Original Dent No.522 Table Regulator

Original Dent No. 522 Table Regulator

This is one of the Dent table regulators I took inspiration from when designing and building my clock.
Finished Mulligan No. 8

Finished Mulligan No. 8

Constructed over 12 months, this is the final clock. It is the 8th clock I have built. Keep an eye out for my most recent project, an interpretation of the famous Breguet ‘3-Wheel Skeleton Clock’.