A little intro: This house in Sagamore, Mass is owned by some very nice and interesting folks who sincerely want to do the right thing in a proper historic restoration. The early part of the frame is from roughly 1725 (we found some sapwood recently which may allow us to do some dendro on at least part of the house). The addition (left) was put on not long after the first was stood. There are stories about carrying pieces across the frozen tundra of Cape Cod Bay but it’s hard to pin these down.
Michael, John, Andrew, Keith and I have all worked on the house at one time or another. Before the gorgeous new windows and clapboards can be applied (historically researched and hand-crafted), portions of the frame are often found in need of repair. Our latest ground-zero on the Sagamore house is a post in the addition which needs a scarfed infusion of new oak to replace its naughty bits…
Below is a closer look. It’s likely the addition (attached sometime after 1725) was repaired with a scarf joint of its own at either the same time of the addition or sometime not long thereafter.
John and I jacked up the frame to carry some of the load while we went about our work.
We cut away the structural dust, and examined the remainder–
Some cool things revealed themselves once the dust settled:
This half of a mortise showed a bunch of stop cuts in gnarly grain. Clearly, the carpenter was an ANGRY elf…!
Once we excised out the rotted parts of the post, we saw two fine and ordered girt tenons which met at a right angle in the post’s center:
The long grain on the left girt tenon looked as though it were cut 2 weeks ago, while the end grain of the tenon’s shoulders (as well as the inside of the pin-hole) was a little the worse for wear. The end grain of the left tenon was in good shape, but that on the right hand tenon was more generally, meh. There are seemingly endless variables in the ways that oak can decay, but it all just seems so flippin random sometimes. Check out that sweet little chamfer on the tenon end! It’s a far hew and cry from the harried chopping at the bottom of the mortise.
And look what came out of the joint after we pulled it apart.
Puuuulling…Look! Look what 288 years, give or take, hath wrought on this pin!
That’s one bad-ass draw bore! (Intentional mis-alignment of holes in tenon and mortise when joining green wood in order to allow a tapered pin to pull the joint tighter). Below, the tenon’s “drawing” into the mortice holds fast, even after the pin is removed. You can see how aggressively the tapered pin pulled the green oak together as it was driven in.
Ergo, he says in his best professorial tenor, this salvaged little octagon of riven quercus tells us a few things:
- Draw bores really work and a little 1 inch white oak pin (definitely white oak– I could smell it as I sawed through) can take an amazing amount of stress for centuries and keep on ticking.
- And see how the pin above has a radius cut out of it on its end? The pins on the front wall post and girt were driven in first, meaning the front wall was assembled and lifted into place before the end wall. After the trenail was driven in, the end wall girt tenon was put in its mortise and a hole bored through both its tenon and the tip of the trenail coming in from the front wall girt tenon. Like butter. A frame’s raising sequence can be gleaned from a single geriatric, though tough, pin.
- I need to get another hobby.