Chipping out at the Fort

Work on the Fort's new staircase is just starting. We've taken out one beam to make room for it, and the next job is to put in place a trimmer and a curtailed joist, after cutting into the trimming joists. I wasn't originally quite sure which is which, but putting these in let you have a space for the stairs that is bigger than the gap between the floor beams.

Our neighbour supplied the oak that will be going in, and it's been sitting on the floor underneath the opening while we tried to work out the exact size of the new stairs. As we've now taken that decision, we've marked the beams for the mortices and I have just started cutting them.

This one is in progress:



The beam is about 25cm square (10 inches as we used to call it) and the oak it's made of was probably felled five or six hundred years ago. It's not impossibly hard, and once you cut through the outer layer - with a little bit of worm - the rest of the wood is very nice. It cuts very cleanly with a chisel. 

Here's one I finished earlier:



You can just see on the left side of the cut where - many years ago - a wooden peg (I think these pegs are properly called "treenails") was inserted into the beam to hold down the floorboards above. This is a little deeper than needed: the "trimmer" will sit partly into the mortice, and partly on top of the beam, in order to have as much strength as possible in both the old beam and the new one.

The work is made just a little more difficult by the fact it has to be done on top of a stepladder two metres up off the floor, weilding a wooden mallet and a chisel. But that's easier than trying to perch on top of the joists, and involves less bending, too.