I’m going to step back from the marking out of wood pieces to talk about some of the seat joinery and the likely reasoning behind it. Most of the joints seem less robust than you’ll find in European woodworking. Everything about EA2476 has been pared down to the absolute minimum and all this fragile joinery works together as a seating “system”.
The higher joint in the original means a downward force on the seat will do less to tip out the sides. The drawing below is greatly exaggerated but it’s the sort of movement that’ll take a toll over the long term.
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Judging the centre of the tenons from the position of the pin holding them, it’s apparent that the end slats have their tenons set away from the outer edge.
This is done to avoid having a side frame mortise too close to the corner (which would make it very fragile) but it introduces a new problem – the outside edge of the seat slat has less support and is liable to rotate downwards.
To remedy this, the end truss work is inset enough to be more “under” the slat and perpendicular to the rotation. If it were set flush to the edge (like the side trusses are) it might be liable to split it off.
So back to cutting wood…
I marked out the leg sockets and cut them away. At the bottom of the cut, the saw barely touch the bottom inside edge. I worked out the seat side thickness on the drawing to line up like this but until receiving a straight on end view photo after the build, I wasn’t certain my side thickness was correct. It’s one of those efficiencies of design that only come to light when you’re building something.
The dotted pencil lines on the right hand piece show what I sawed away to get closer to the bottom finished shape. It’s best to leave some “meat” on at this stage because the curvature midway between the edges is easy to accidentally cut into. I brought this closer to it’s finished shape than needed because I wanted some reassurance the shapes were working together. Leaving more flat sides makes clamping/work holding safer and easier.
I marked out the mortises next. I drilled them using this simple guide block, both for the correct angle and as a depth stop. Chiselling the waste followed.
They’re all a bit over an inch deep. The mortises on the near end became a little wider than originally planned but it don’t think it’ll be a problem.
Next instalment we’ll be making the slats.
Fossil Brains 