Cantilever Spiral Staircase

Today I had the chance to visit an old job that I worked on when I was a draughtsman at a stonemasonry company. I didn't design this but had to take the architect's drawings and literally redraw them and break the staircase up into individual stones for production. This is quite a unique cantilever staircase in as much that usually one end of the tread is recessed into a wall. The staircase is designed so that one end is in the wall and the free end is supported by the tread below it. This staircase being in the middle of a room posed a problem. To overcome this there is a hidden spiral metal support on the right hand side as one walks up. The metal support runs from the ground floor and is fixed to the floor above. It has been cleverly hidden by stone cladding. When the metal beam was originally made it was in one piece which made it difficult to transport so in their wisdom it was cut in half to get it to site. Unfortunately as it was manufactured certain stresses were induced into the beam and on cutting it into two it totally went out of shape. It took alot of work to get it back into a usable piece of engineering

I lost several night's sleep when working on this job. After it was installed I wondered what all the fuss was about.

I thought you all might like this unique and beautiful design.