I think one reader was a little upset with me for attaching the legs before bottoming the seats of the two forest chairs, so these lath-back Windsors were done vice versa. Natheless, the weather impelled me to bore all the holes in the seats, cut all the mortises and test fit the backs before bottoming them (figs. 1 & 2).
Fig. 1. The day started out at -6°C (21°F) …
Fig.2. … but then the sun appeared and the frost retreated.
When finished with the angry grinder, I scraped the seats and gave them a final sanding before gluing the chairs together (fig. 3).
Fig. 3. The lath-backs in-the-white.
Fig. 4. As tradition would have it, the laths are pegged top and bottom.
Jack Plane
Pegs and 'Tails 
How would the lath be pegged on the bottom end?
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Through the back edge of the seat.
JP
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Anyone who has ever tried to lay sight lines and resultant angles (even and especially when using some type of jig) on a seat that has already been “saddled” (bottomed) will appreciate your process. I suspect that many craftsmen of old used exactly the same approach, contrary to the currently popular method of saddling first. Kudos for your willingness to “buck the trend”. Good on ye.
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I mark seat templates with the leg sight lines, but don’t actually transcribe those lines onto the undersides of the seat boards. Rather, I position the drill on the template at the requisite angle and rely on muscle memory (or whatever the popular terminology is) when boring the leg sockets.
I’m impatient, headstrong and lazy, so little things like attaching the legs prior to bottoming the seat means I don’t have to worry about the drill busting through the top of the seat.
JP
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BTW, I see you used elm for the seats. How much “stretch” did you need on the center stretcher when using the “hard stuff”? When using softer wood like pine or popular, I’m always surprised at the additional length required on that stretcher to “stiffen” the “undercarriage.”
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I can’t give you an exact figure for the amount of stretch, simply because I don’t measure it. I visualise it with the stretcher in hand.
This raises a valuable point: I don’t cut the stretchers so as to stretch the legs to capacity; rather, I stretch the legs almost to their limit and then cut the stretchers somewhat less. A little ‘give’ is essential to prevent breakages.
JP
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