A History of British Safe Making Part 2

The glory years

The market for safes designed to preserve ledgers from loss by fire was booming and scores of small manufacturers quickly became established, many of them in the West Midlands.  Chubb established a factory in Wolverhampton and opened its first London offices in St Paul’s Churchyard.  Meanwhile, in 1912 John Tann moved their London office from 11 Newgate Street to 117 Newgate Street.  It is often said that this was because their offices backed on to the execution yard in Newgate Prison but this is probably apocryphal

Meanwhile, in 1835 Chubb patented a safe that was ‘resistant to the tools of thieves and burglars’, recognised as the first burglar resistant safe. Milner’s, one of Chubb and Tann’s major competitors continued to market safes designed to resist fire.  Most safes in the late Victorian era were filled with sand and sawdust in the hope that they would provide some level of protection for paper records, but it was Milner’s who added alum crystals to the mix.  When heated these crystals converted much of their bulk to moisture which in turn damped down the sand and sawdust.  Whilst the interior of the safe was filled with steam, the temperature would remain around 212° – the boiling point of water, well below that at which paper would begin to char. The number 212 is often incorporated into the maker’s trade mark. 

By this time Chubb had been awarded the Royal Warrant and was entitled to display the Royal Coat of Arms. There was much competition between the principal manufacturers each claiming their safes were the most fire proof.  Challenged by a competitor to demonstrate the heat resistant qualities of their safes, two large pyres were constructed, on the heath.  One for the competitor’s safe and one for Chubb.  A live rooster was placed inside each safe and the wood set alight.  The fires raged fiercely. The brass badges and escutcheons melted and ran down the face of the door.  The fires blazed for 3 hours and were then left to cool down overnight.  The following day in front of the national press gathered on a clear and frosty morning, the competitor’s safe was forced open. The rooster staggered out into the morning light to be greeted with cheers and applause.  Then the Chubb safe was forced open. To everyone’s disappointment the rooster lay in the bottom of the safe, dead.  However, not to be dismayed, the Chubb group insisted the chicken was forensically examined.  And sure enough it was discovered that the bird had frozen to death overnight.

True or not the publicity was excellent and safe manufacturers began to make their safes even more resistant to both fire and theft. The earliest safes preceded the invention of hydraulic metal presses so they were generally constructed from cold rolled steel plates riveted to an angle-iron frame.  This created sharp 90°angles so these safes were referred to as ‘square cornered’.  However, the joins were found to be vulnerable to being forced open by the use of simple hand-held tools and levers.  Safe makers tried a number of remedies including wrapping steel flanges or bands around the front and rear seams.

Gradually the introduction of cold steel presses allowed manufacturers to try various ways of protecting these seams and the pressed shapes became more and more complex. The early models were known as 8 corner bent safes followed by 12 corner bent safes which look very much like today’s safes.

The fabrication of the doors was also evolving at a pace. Instead of the locking and bolt-work mechanisms being assembled inside a detached pan, which was then screwed to the back of the door plate, they were welded directly to the door plate and covered by the addition of a fire pan.

Many attacks in the Late Victorian area used black gunpowder poured into the lock chamber and ignited.  Milner’s designed a lock where there were no gaps of hollows in the body of the lock into which an effective quantity of powder could be introduced. This was patented as the ‘Milner Solid Powder Proof Lock’.

A major step forward was the development of the anti-explosive re-locker.  This was a relatively simple device.  A block containing a spring loaded pin was mounted on the door.  The spring was held back by a wire or cord trapped under the lock.  If the lock was blown away it released the cord or wire allowing the spring loaded pin to engage in the bolt-work to prevent is being unlocked.  They were referred to as ‘anti explosive devices’ but eventually the wires or cords were attached to a piece of tensioned glass placed in front of the lock.  If the glass was touched by the tip of a drill, the flame of an oxyacetylene torch or an explosive force, the glass would shatter to release the re-locker.

New barrier materials were invented to protect the body and door of the safes. Chubb’s was TDR (torch and drill resistant) a mixture of aluminium and aluminium oxide nuggets.  The aluminium conducted heat very rapidly so if an oxyacetylene torch was used on the door, the heat would be constantly drawn away and dissipated throughout thereby preventing it reaching the critical temperature necessary to start a cut running. 

On very high security safes, copper was substituted for aluminium.  It was even more effective in producing a ‘heat sink’ but was obviously vastly more expensive.  Whilst both aluminium and copper were soft, the oxide nuggets were number 2 on the scale of hardness (diamond is number 1) making it virtually impossible to drill. Percussive tools such as power hammers would be defeated but the ability of aluminium and copper to absorb shock.  Chubb’s claim was that they could ‘bell cast’ the hot aluminium /oxide nuggets into a preformed body shell so there were no seems to be attacked. 

Tann’s answer was ‘Adamantium’.  This was concrete into which was poured chilled iron shot.  When the concrete cured, it shrunk slightly so each little piece of shot could revolve.  When it was attacked using drills, the drill bit would be blunted by the hardness of the Adamantium, constantly deflecting the drill tip.  The wet concrete and Adamantium mix was poured over steel mesh reinforcement to hold it all together.  Diamond drill core cutters, similar to those used in the Hatton Garden Vault attack, were ineffective against core drills as the little round pieces of chilled iron shot just rotated until the core drill was blunted or shattered, Both methods of construction are very effective.  However, Tann claims that if you can find an effective tool to attack TDR you only have one barrier to worry about, whereas Tann’s barriers pose a series of barriers, each needing a different attack tool.  Chubb on the other hand would claim there were weak barrier interfaces that could be subject to delamination.

This competitiorivalry between major safe manufacturers, each wishing to claim their safes as the best in the world, was an incredible marketing tool and British safes were recognised as the undisputed best in the world.  Central Banks anywhere in the world were almost certain to have a Chubb or Tann central vault.

The 60’s and 70’s saw the heyday for British safe makers. Their products were head and shoulders above any competition. I was one of 30 Chubb territorial salesmen supported by specialist data protection consultants. There was a thriving export division with agents all round the world and in the heart of the City of London, a Banks Security Division served all the main clearing banks.  

Just three decades later, everything had changed. Today Chubb, Tann, Fichet Bauche and Churchill exist only as brand names owned by the same Swedish conglomerate manufacturing in Indonesia, France, Sweden and China.  Apart from just two or three UK manufacturers the overwhelming majority of safes sold in the UK are manufactured elsewhere.

This article is the property of Mike Palmer and cannot be replicated or used without Mike’s express permission.



24 November 2019


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