Belt and suspenders.
Today is not about restoration but about shoring up the floor system in the north bay. Although three floor joists will have been replaced, and two others sistered when Michael and Virginia are done, it is safer to provide some extra support for the large span. Besides, I’ve been told I am not allowed to set up a horse driven cider mill like in the old days.
This was the most amazing thing I have seen Michael and Virginia do on the cider house so far. Michael has built a two-part dropped header to support the joists of the floor above. The first part was done while I was busy with the sheep, but from this you can see what the goal is for the second part, which I will show you.
The each part of the truss assembly is composed of a dropped header held up by a post sitting on a concrete footing with braces, all pinned together with wooden pegs. The far end will also be supported by the stone wall. The two parts will then be joined together with a scarf joint.
To set up the second assembly, Michael and Virginia first raise the second dropped header so the post and braces can be joined to it with mortises and tenons.
With the second dropped header at the height of the first one, you can see why I think this is so impressive. This is called a scarf joint. It allows you to make a long timber out of two shorter ones. To get the timber on the left on top of the timber on the right, it must be slid about two feet to the right so the scarf joint closes and the supporting post sits on the concrete footer.
But first the post and braces had to be fitted to the header with mortise and tenon joints.
Virginia used a come-along to lift the the post and braces so the tenons slid into the mortises of the header, which was suspended from the joists above.
The final step was to slide the post+braces+header about two feet to the right so that the two headers are joined at the scarf joint with the post sitting on the footing. Phew! The bottom of the post has a slot that will slide over the knife plate on the footing. It also has three holes that must line up with the holes on the metal blade to accommodate metal pins.
So here is the entire structure ready to be moved into place. You can see why it was necessary to use the scarf joint to install this support structure in two stages.
Using the come-along, Michael very slowly and very carefully slid the structure into place.
With some encouragement from a mallet, the post slid over the knife plate on the footing.
And the scarf joint closed, needing only a couple of whacks with the mallet. Now it is perfectly aligned and level. Magic.
The final steps where inserting wooden pegs into all the joints and shims between the dropped header and the joists above. The metal pins at the bottom of the posts were hidden with peg nubs.
Next, work moves to the west side of the cider house where another sill must be replaced.