done

I finished the chair yesterday. Somewhere along the way I drew up this template showing the sightlines I use to bore the leg mortises. I tape it right to the battens, stick a block of scrap wood under it so the adjustable bevel will sit on it and set the bevel & bore away.

sightlines

It works pretty well. The auger bit chews up the oak battens some because it’s canted over pretty far – 25 degrees. Having the back’s uprights in place helps keep the legs from hitting those through tenons coming down from above. The back edge of the template is 4 3/4″ from the seat’s back edge. It worked perfectly, the legs miss the tenons by about 1/4″ or more.

boring leg mortises

Usually on the old chairs, the leg tenons come through both the battens and the seat. This cross-grain construction – the battens run perpendicular to the seat – almost guarantees that the seat will crack. Except sometimes it doesn’t. In all of my previous versions of this sort of chair I did the joinery so the leg tenons only penetrated the battens. This time I made the leg tenons long enough to come all the way through. So I threw the switch in my head that told me not to do it – and bored the mortises through the battens and seat. And glued and wedged the legs in place.

in for a penny

I didn’t think I’d like the tenons poking through the seat board, but I do. It’ll show up better when I put a finish on the chair. Then decades from now it will be harder to see again. Ash legs, butternut seat and back.

July 2022 brettstuhl

I’m going to tinker some more with these 3-piece backs, but I do have some wide walnut waiting to be brettstuhls. And one more ash bolt to rive. Better get to it.

3 thoughts on “done

  1. Visually I am rather taken with the proportions and the detailing on the back. Be good to see it with a finish, nice work Peter!

  2. Thanks a bunch Peter, I have seen Chris S explain it but it makes so much more sense seeing it.

  3. Drilling off-centre holes with an auger presents a problem with clean edges both front and back – as you found out. I had a similar problem a while back, but, with a little unorthodox effort it can be done.

    Here’s how.
    Razor-Sharp wing-edges on the bit are essential.
    Start your drilling the hole vertically as usual, ensuring that the cut edges from the wings are cut clean, then using some judgement, bore down until the chisel section of the auger bites….. about 1/8 t 3/16 inch or so.

    Withdraw the bit, plug the auger screw-hole completely.

    Start a new pilot hole for the auger screw at the angle you require and carefully enter the hole with the wings lined up top and bottom, swinging the bit as you carefully start the cut.

    It is best to glue a lump of scrap to the exit side to ensure a clean cut on the way out if you are going right through.

    Good luck…

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s