Inside Brompton's factory in London where over 1,000 folding bikes are made by hand each week

• Brompton Bikes is the UK's largest bike manufacturer.
• It makes over over 45,000 bikes per year.
• The Brompton was invented in 1975 and can be folded down in 20 seconds.
• Each bike is created by hand in Brompton's London factory.

The Brompton factory in London makes 1,000 folding bikes per week. The process starts with steel tubes, these tubes are cut to length and put into an auto-brazer. The auto-brazer attaches machined parts to each tube.

Each part is then cleaned in an agitator. Once cleaned they're bent into shape and joined together to form the frame. Each bike is hand-brazed, this is a similar process to welding but uses lower temperatures and doesn't melt the metal being joined together.

This process allows Brompton to use thinner metal and produce lighter bike frames. It takes 18 months of training to become a brazer at Brompton and each brazer stamps their initials onto the frames they work on.

Each bike is made up of around 1,200 parts and each is assembled on site. Colours and features of each bike can be customised, from different gearing to the style of handlebar.

Brompton bikes are available from £840.

Produced by Charlie Floyd