The first flight of stairs is now beginning to go up. The bottom step has a bullnose: the idea of this is to set back one of the newel posts to make the entry to the stairs a little wider. It's traditional to make the end of the stair that sticks out a rounded shape, because using a rectangular end looks a little crude (I drew it out that way first and it didn't look quite right).
It can be seen here in the middle of the bottom of the picture:
This type of step presents a number of challenges, mostly of the "you'd better measure it all very carefully before cutting" kind. It's rebated differently at either end, and it can only be put in place with difficulty once the newel post on the right is fixed in place. But it has to be done in that order (newel post first, then step) as the newel post needs a bit of manipulation to get it in place once the stringer is attached to it. I have cut a semicircular "cheese" of wood to go under the rounded end to provide it with some extra support - a corbel attached to the riser below the stair.
Here is the right hand end of the step.
The joint fits very nicely, but I didn't quite get the cuts in the newel post right first time - but luckily they were too short rather than too long. The idea is to make it look as if the whole of the back edge of the step passes straight through the post: in fact there's only a centimetre groove cut out of the post: the remainder is cut from the step.
Underneath this part of the step is some hidden superstructure that will eventually give support to the newel post. The post will be braced by the step itself, by the riser above the step which will be mortised lengthwise vertically into the post, and by the (heavy) stringer which will be mortised into the back of the post. All of these mortises are yet to be done.
Here's the other end of the step. Again it's a nice tight joint.
One problem I get is that the parts have to be disassembled more than once, and doing this tends to splinter the top of the rebate when the step is pulled out. I don't have a solution for this.
Finally, the current work in progress.
I am cutting the top of the next post back into the beam above it. It's very old wood but once through the surface worm-eaten half-centimetre, it is good to work, though hard. I have something of a problem in prospect of fitting the post in place once it has the stringer attached, but I think the way to do it is to usnscrew the plinth it sits on and slide the plinth into place once the post is seated on it. I'm shaping the cut in the beam on top with a slant so it can go in at an angle but appear to be squarely cut once in place. We'll see if this works.
The first flight for the Fort - technically, I suppose, it's the second one, but the first flight isn't yet assembled - is now in place and screwed up. And screwed down. And wedged. And pinned .....
Everything is level and the mortices are nice and tight. They are draw-bored, so that hammering the pins in pulls them a little bit closer together. The hole in the tenon is set slightly closer to the newel post than the holes in the morticed newel post. The pins have to be hit very hard to get them to go in the way they should, and I broke a couple before perfecting the technique. A lttle bit of glue helps to act as a lubricant.
The wooden pins in the mortices have been cut off flush. It was a revelation to find that there's a special flexible saw for doing this, with teeth that are set only to one side so it doesn't scratch the surface of the wood.
The underside will eventually be planked over, so almost nothing here will show:
The last picture shows how the wedges go - and they go in after being walloped very hard indeed: it's all oak so nothing splits ....
I think the vertical wedges for the risers need to be pinned in place, or else they could work loose. The horizontal ones are partly held there by the risers, but I'll pin those too. I plan to leave the stairs open like this until the end of the summer, when I'll give the wedges another good whack with the club hammer. There will probably be a bit of shrinkage and that should take it up. Anything after that will just have to be a normal consequence of timber construction.
One of the things I've learned about using glue is that you don't want it show when you've finished. It seals the surface of the wood, so that any subsequent treatment - stain or varnish - won't take properly in the area that has glue on it.
So you have to make sure that the glue goes into the hollowed-out portion of the joint, not on the part that will be going into it. If you glue a peg, as you knock it in, the glue stays on the edge of the hole.
So here I am trying to get the glue carefully into the 12mm hole, without touching the edges:
I found out later it's easier to do it with a flat chip of wood narrowed down with a chisel, rather than with a round peg (as shown here). Once the glue is in the hole, all that's needed is to give the peg a really good thump with the mallet:
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Nevertheless, I broke two pegs, and had to knock them out again from the other side.
