During WWII, part of the Lainchbury works was involved in vital war work, and to that end on October 7th 1940 Lainchbury and Sons Ltd commenced munitions work for the war effort, largely organized by Mr Charles Lainchbury.
Throughout the war, a range of items were made including rocket heads and parts for mines such as bulk heads for magnetic mines.
It is not known exactly what items Lainchburys manufactured for the war effort however one item in particular remained on the official secrets list into the 1960’s, sometime after the war had ended.
During the war Lainchbury's continued to manufacture their normal peace time agricultural items as these were also essential for the war effort. Items such as winches and elevators. You can find some pictures of these being made on the page entitled Inside the factory
One of the items made were rocket heads, and quite a lot is known about them now, and many still survive. These were not actually used directly as a weapon they were used as aiming devices and emitted light from the holes around the top. You can read more about the rocket heads here Rocket Heads
The other item machined at Lainchburys was a large circular disc which was very secret at the time and for a long time afterwards.
The purpose of this disc was only known by Mr Charles Lainchbury and it seems that only two people at the works were involved in machining this very secret part, one was a young lady named Winnie McCabe and the other Roy Sole.
The part in question was a disc or end cap for Barnes Wallis’ so called “Bouncing bomb”. In actual fact, this “bomb” was not a bomb at all; it was a mine with its proper name being ‘Upkeep Mine’. The mine of course was used in the famous and effective dam’s raid which took place on May 17th 1943, as portrayed by the movie “The Dam Busters” where the term bouncing bomb originated.
Lainchburys did not do all the manufacturing of the mine as they were only involved in machining the end caps or discs, one of which was fitted at each end of the mine. The discs themselves were cast at the Hub ironworks at Chipping Norton, who incidentally had a long relationship of casting items for Lainchburys. The discs were then sent to the factory for machining.
Roy Sole made and erected a special hoist to lift the discs up and on to the turret lathe and down again after machining, the discs must have been very heavy! Winnie worked on the discs on one shift and Roy on the other.
The bomb was some 50 inches (1270mm) in diameter and 60inches (1524mm) wide.
Barnes Wallis inventor of the Bouncing bomb
You can see the massive size of the bomb from the picture
At the time it was said that the discs machined at Lainchburys were amongst the most accurate produced. Accuracy was important when one considers that the actual mine weighed 9250Lbs (4195.7Kg) and was spun backwards at 500rpm before being released.
The day after the dam’s raid had taken place Mr Charles Lainchbury took Winnie McCabe aside and informed her that the part she had been working on had played a vital part in the raid.
As mentioned above Winnie McCabe was involved in War work at the factory and David Lainchbury, Charles Lainchburys son recalls that during his school holidays he worked some night shifts at the factory and well remembers Winnie McCabe and her lifelong friend Eileen Tolley who both almost always worked on the night shift.
David remained in contact with Winnie over the years musing over the items made during the war years. Winnie's married name was Murfitt she passed away in July 2012 age 93.
In 2006 Winnie McCabe (later Murfitt) wrote her own war time story which you can find here here.
The Mohne dam breached.
Lancaster bomber carrying an Upkeep mine
Diagram of how the mine worked
An unexploded upkeep mine captured by the Germans
The Breached Mohone dam
I am indebted to David Lainchbury for some of the information included above.
Next page Rocket heads