Bremont Parts Manufacturing in Silverstone
Near the grounds of the famed Silverstone Circuit, one of the most historic and iconic Formula 1 racing venues in the world, is Bremont's case manufacturing facility. This facility in the Northamptonshire villages of Silverstone is about a ninety-minute drive from their headquarters in Henley on Thames. Ultimately, Bremont will expand their headquarters to house the machines that are currently in Silverstone. For now, however, it makes a lot of sense to have this type of manufacturing next to the other high-end fabrication concern in Great Britain, which of course is their storied high performance automotive industry.
As our host, and Bremont co-founder, Giles English pointed out, though the tolerances are different between Formula 1 fabrication and the creation of watch cases and components, it requires the same type of skills to operate the computer numerically controlled (CNC) equipment used for case cutting and polishing. Just as the skill set of watchmakers were raided in the past by other industries, today Bremont cases and components are made by highly skilled and experienced craftspeople that until recently were honing their skills in the automotive industry.
While this evening is the historical limited edition launch, and that effort will no doubt be an impressive integration of history and artistic expression, at the base of the watch, and for that matter every Bremont, is a case cut in the U.K. Below are some pictures and descriptions of the Bremont manufacturing machinery that I saw today.
Bremont starts with bars of 316L stainless steel and bronze. The steel is for the watch cases and the bronze is for the manufacture of components. While Bremont will continue to invest and purchase the machinery necessary to manufacture a greater percent of its parts themselves, the main watchmaking component that they showcased was the creation of the base plate on their BR-01 Calibre. More on that later, but here is a photo of the long rods that are the starting point for their cases.
A 45mm bar of 316L stainless steel destined to become Bremont watch cases.
The specially bladed saw that cuts Bremont's 316L steel into blanks for the milling process.
This is one of Bremont’s most expensive and customized prices of milling equipment. It costs around 1,000,000 pounds and cuts and drills Bremont's cases. Giles told us that a complicated case such as a MBII takes 40 minutes to mill, while a simpler Solo case takes merely 25 minutes. This machine runs 24/7 and is completely automated. Giles said that one of the most challenging aspects of the manufacture, and where operator skill comes in, is accounting for subtle differences in the exact wear of the machine parts which is constantly changing. What differentiates their process from many other watch brands is that their cases are never stamped in the forming process. This is because form stamping alters the strength of the steel. The program that controls this computerized machine is sophisticated enough to create the entire case shape, including drilling the holes for the internal bezel and crown.
A MBII case that has been partially milled from the 316L blank. This one is midway through a 40-minute fully computer controlled program.
After the case is cut, it moves onto the surface finishing process which uses a combination of computerized polishing machine and a manual process performed by a polishing expert. The machine does a combination of sanding, washing and rotating. Brushed cases use one type of surface finishing belt while high polished cases use another.
Giles English described the process of polishing the cases with the sophisticated machine behind him. Rather than an uninterrupted process like the case cutting machine, it instead undergoes a series of several five to ten minute programs. It is then sent on to a different station where a watchmaker applies a finishing touch.
A watch case being sanded and washed.
Bremont cases getting hand finished before being sent back to the automated polishing machine.
The one part of the case manufacturing process that is not done at Silverstone is the case hardening. This work is still being performed at the same off site facility that performs the hardening of Rolls Royce jet engine turbine blades.
The Silverstone facility also manufactures the base plates for their proprietary BR-01 movement. The BR-01 base plate is milled out of a bronze blank, then moved to another facility for plating.
Giles showcasing the facility where the BR-01 base plate is made.
The BR-01 base plate as it appears in bronze after the computerized milling process.
This machine laser engraves all case writing, movement serial numbers, and watch numbers for limited editions.
Thank you to Bremont for the access, hospitality and insight into how their cases are made.
This post will be updated with two videos with Giles English describing the case construction process.