Popular Woodworking – October 2019

28 ■ POPULAR WOODWORKING

Straightest Path to a Great Chair

13

14 15

13 For the slip tenons,

plane the stock to a snug fi t,

then rip to width and round

the edges.

14 Mark the location and

orientation of these tenons

in the seat frame.

15 Mortise the front and

back rails. Be sure the

mortises in the back rail

(and crest rail) are located

so they will stay inside the

curves of those parts. Mor-

tise the legs too.

Add the Crest Rail
Next I cut the joinery for the crest
rail. Once again, because the back
legs are vertical and parallel in the
front view, the crest rail can be the
same length as the rear seat rail, and
square in its ends. With legs that
twist outward, the crest rail can be
very tricky and time-consuming to
cut, join and fi t.
I switch to a^1 / 4 " tenon here so I
can get the reveal I want between
crest rail and back legs without the
tenon popping out of the curved rail.
And I make the mortises in the legs
an extra^1 / 8 " long so the crest rail can
be pulled down tight on the lumbar
slats later. I take the position of these
mortises from the back-leg template.
Once the tenon stock is glued into
the crest rail (which is still a thick
piece of stock at this point), I can
dry-fi t the back of the chair. This
reveals a complication: Because the
back legs are curved and the crest
and seat rail also curve, the bottom
edge of the crest rail and top edge
of the rear seat rail are not parallel
to each other, which means the two
center lumbar slats would have to be
slightly shorter than the two outside
ones, with angled ends.
My trick for avoiding this compli-
cation is to bevel the bottom edge of
the crest rail and the top edge of the
seat rail to 10° before cutting their

curves, so these edges end up parallel

and square to each other in the chair.

After making these slightly

angled rip cuts, I lay out the curves

again on those edges, and cut the

curves on the bandsaw. I always

start with the concave side. That

gives me a square side to rest on

the bench when smoothing them

(with a big curved sanding block).

After the fronts are sanded, I cut

out the back curves. The rails

rest steady on their two ends as

I smooth the curves with a ran-

dom-orbit sander.

The Slats and Back

To fi gure out the length of the

lumbar slats, I dry-fi t the rear legs

and rails, tap the crest rail up to the

top of its extra-long mortises, and

measure down to the seat rail. That

leaves room for the crest rail to push

down tightly on the slats with no

gaps. Then I cut the slats to length.

Since the inside edges of the rails

will be square to each other, the

ends of the slats are square too.

Because this “occasional” chair

leans back a little more than my

dining chairs do, it gets a lumbar

curve that is less pronounced. I use

a template to mark the curves on all

four slats.

The ends of the slats are square,

but the tenons will be going into a

rail that is angled at 10°, so I tilt the

slats the same amount when mor-

tising them. Before gluing tenons

into the slats, I use the mortises to