The old adage that ‘necessity is the mother of invention’ is very true of the AKWAMASTA story.
In Autumn 1967 I had just started work as a Building Inspector in the Engineering Department of Merthyr Tydfil Borough Council. One of my first jobs involved a recently completed bungalow which was 150mm out of level at DPC, causing problems with fixing skirtings and potential damp walls.
Adding to the problems were gang nailed roof trusses fixed on a seriously out of square building, showing soffits tapered or out of parallel – not only ugly but creating more work for the carpenters fixing the roof.
As part of the early move towards a new regulatory framework, a new form had just been introduced for the statutory inspection at DPC level. This required Building Inspectors to certify the degree of accuracy for level and square of structures.
As an inspector on site visits I was usually working alone, and had to return to the office for a dumpy, tripod and an assistant, who were often not available for a day or two. As Building Regulations stipulated inspections completed within twenty-four hours this was a major problem.
My department chief agreed to buy-in any instrument which would enable one-man operation for levelling over the distances required – up to 20-30 metres. After a prolonged search over several months, including approaching a number of Colleges and the Building Research Establishment, it was clear that no such tool existed (and as far as I am aware that is still the case). There was no alternative but to make something myself.
It was obvious any optical instrument would involve two operatives, so that was not an option. At the time I had little knowledge of water levels, having rarely seen them in use. They seemed to be used by specialist contractors, such as shop fitters and false ceiling fixers, and were only able to compare points between two vertical surfaces. In any case they needed two operatives and would not determine differences in level of, for example, manhole inverts.
After much deliberation and research I made my first working model using a six foot length of three quarter inch dowelling. I laboriously cut a groove top to bottom in the timber and glued in a length of clear, plastic draught excluder tube, with a wing to nail it to a door frame. I cut a two foot length of three quarter inch copper tube its full length, and sprung it open enough so it was a nice slide fit over the dowelling.
I then glued two lengths of linen, seamstress tape, twelve inches either side of the centre of the sliding copper cursor, which allowed me to read off a difference of level of up to a foot directly up or down. I attached the wing tube to a ten-yard length of windscreen washer tube, the other end to a one-gallon plastic container. [continued on right]