In October of 2015, I began to move earth and construct the arch of the kiln. I wanted to try something different for my arch.
Chain and catenary arch construction is done by hanging a chain to trace the shape that it makes to build the arch. That makes a strong arch but it'll eventually fail, collapsing, in the bottom third of the wall.
A barrel creates an arch that is any part of a circle. When it's initially built, it will still be a curved arch, but once it's fired, everything will expand and the top will flatten out in cooling and eventually fall in.
A barrel creates an arch that is any part of a circle. When it's initially built, it will still be a curved arch, but when fired, everything will expand and the top will flatten out in cooling and eventually fall in.
The point for me, was to find an arch design that's in between the catenary and barrel design. I found that bending a pipe will create a line right between the two. I think it will be a stronger arch--I may have created a new problem too but we'll see!
I've never seen the arch building technique that I've used done before and I'm confident it will work. I spent several months working out the details of my arch design on my own and decided to go for it.
I had already almost completely planned the kiln by this point, however I did end up spending a lot of time working on the depth and steps to ensure the arch was not out of the ground. I did not want the arch out of the ground for two reasons: 1. to save money and buttressing through allowing the Earth do the job, and 2. I wanted to be able to stand at the tallest part of my kiln and still see the person stoking on the other side.
Having completed the arch form and sighting every single strip, I was satisfied to move on to the next phase of the build--bricking the arch. Stay tuned for more.