Boulle Clock Restoration

Here is the story of the restoration of a XIXth century Boulle mantel clock in black backed engraved turtoise shell and engraved brass.

18 months ago we started to work on a Boulle clock restoration for a gentleman back east.
We received the clock piece by piece, starting with the top to show the process and what we could do to our client.

First thing was bronzes removal

The lose brass elements where lifted and then, the fish glue in the cavities was rehydrated and removed, and the back of the brass elements were scraped clean.

Missing pieces are drawn by rubbing on a thermal paper

The missing elements are cut on brass or on pre CITES restrictions black backed tortoise shell.

All missing elements are cut in shell and brass

To glue the pieces on curves we use sand bags to obtain even an strong pressure. We use the traditional fish glue that enables future restorationd and has a strong sheer factor, very important in glueing metal to wood.

The cleaning is done with “eau japonaise. I do not like to use it when there is wood elements on the Boulle marquetry, as the acidic content may be to agressive and damage the wood, but in this case it is perfectly fine.

I also discovered the shell was engraved, something I have rarely seen

When everything was restored, I used suit black to fill the brass engraving

Then the shell was re-engraved, the cavity filled with gold dust and french polished. It can be sometime tricky to french polish on brass ans the difference in temperature can bring condensation and give a milky consistence to the shellac.

The bronzes were cleaned and installed

Our client being happy with the first part, sent us the rest fairly soon after and I started working on those. The based was the first to arrive. It was the most damaged part of the clock and also the hardest to restore considering the curviness of the sides.

But also because of a lot of missing elements and details on a very tight radius part

Like for the other part, I started by removal of the bronzes, lifting of the lose brass elements and cleaning of the cavities and the back of the brass pieces.

Cleaning and re-glueing with fidh glue using sand bags

And Cawl for the rare flat spots

Before and after cleaning the brass with eau japonaise

I recreated the missing elements using the little informations and inspiration from the rest of the decorative elements

We ordered some missing finials in France using a picture of a similar clock

While waiting for the bronzes to be cast in France, I put the clock to the black at the same time of a Boulle marquetry decanter I was working on at the time