Bill,
You've got a tough one here and, looking at the chair, it may not be worth
all the work that it will take to make a sound repair. If replacing the leg
is not an option then I'd take a chapter out of mast building and use a
double scarf joint here. I've enclosed a pic to go along with the thousand
words. I must have done a few score of this type of repair and it is the
only way that makes any sense to me.
The scarf should be let in fore an' aft and can be accomplished using a
bandsaw if you disassemble the chair or with a Japanese Ryoba saw which
cuts very straight if you want to splice without disassembling the back. I
use epoxy to help with any areas that don't fit exactly. However, if you're
real good with the saw and a SHARP chisel, preferably of the patternmaker's
type (really long, thin blade), any good wood glue will work.
Here's the step by step:
1) Disassemble the back and at the seat rail mark the dowel hole centers across
the
face to the edge. You'll be loosing the dowels and their position when you saw.
2) Saw with a bandsaw or the Ryoba to make a long V down the leg starting
very close to the sides. Do the same to the other leg. The wider you can start
the
splice the stronger it will be. The scarf should be a 1:7 or better ratio of
cross grain to
long grain. A 1 1/2" wide leg (a guess) would need a splice 1 1/2" wide by 10
1/2" long.
3) Cut similar V cuts in the back to match up with those of the leg.
4) Cut out corresponding V's to fit into both legs.
5) Position the back against the splice and transfer the V cuts onto the
remainder of the splice. I like to use a thin knife for these transfers.
6) Finish cutting the V's that will go into the back and fit (easier said than
done!)
7) Glue in the splices joining the broken halves. Epoxy with some bulking agent
is best. I use
West System 105/205 epoxy with 403 or 406 filler to keep the epoxy from running
out of the join.
8) Surface the splices and redowel and complete the assembly.
Notes: Use oversized stock for the splice to allow for alignment. Often this
splice can be made without having to completely disassemble the chair frame.
The Ryoba saw is the cat's meow for this kind of work.
John Coffey
Locust Valley, NY
