Thanks to the generosity of the Heritage Lottery Fund, All Churches Trust, the Beds & Herts Historic Churches Trust, the Francis Coales Charitable Foundation, and the Steel Charitable Trust the new stone windows in our historic Tower are now complete.
As all of the work is largely hidden behind the Monarflex sheeting that the scaffolding is wrapped in, we thought you'd like a sneak peek at what's been going on.
The individual stones were cut off-site using templates produced by our builder. Producing the individual stone components involved a mixture of machine and hand cutting/carving, producing pieces of stone that weighed up to 250KG (a quarter of a ton)!
Each stone had a hole bored in it to allow a 'Lewis Pin' to be inserted. This traditional device, used by the ancient Egyptians, gives a quick and secure anchorage, allowing the stones to be lifted using an electric winch.
The Lewis Pin before inserting into the bored hole in the stone.
Once inserted, the winch hook is attached to the large iron ring on the top of the tool which splays the legs of the pin outwards in the hole, gripping it firmly.
With each stone weighing up to 250KG, moving them into position required some ingenuity - a skateboard provided a practical solution.
Building the windows required the old, badly weathered stones to be removed one at a time (from the bottom upwards), and replaced with the new Clipsham stone sections. The combination of their weight, and the fact that they were being inserted into slots, rather than just built up on top of each other as would be the case with a new-build, meant that this was a very time consuming process. The picture above shows one of the new cill sections in place with the new frames and tracery being constructed above it.
Here you can see the original stone still in place at the top of the window, with the new stone gradually being built up from below. The centre tracery was held in place with timber whilst the lime mortar joining the stones cured.
The first window nearing completion...
The first window completed, just waiting for the new hood sections to be delivered and fitted. Only three more to go...
The hood (made from a harder stone to resist weathering) was fitted, completing the first of the four new windows.