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Part I - The Mortise
One of the strongest joints, the haunched and drawbored mortise and tenon is one of the few that resists stresses in any direction, to include tension, and is a joint that will remain fully functional long after any glue has deteriorated to dust. A
basic joint used to join structural members, I’ll walk you
through cutting one today by hand to join the top rail to its
post for a small work table done in hard maple. Why by hand? Not
because I’m some hand tool reactionary… I use machines for the
jobs they do best and hand tools for the jobs they do best… but
there are some joinery principles best displayed and
photographed using hand tools, and as most teaching today
involves machines almost exclusively, newcomers tend to miss the
parts where the cheaper hand tool does the job much, much more
efficiently than the expensive machine, especially on smaller
hobby projects.
The
basic joinery tools I’ll use are shown above. None except the
shop-made mallet are newer than 30 years old and some are almost
a century old…yet I could replace all of them in a few months of
shopping at flea markets and collectible tool auctions for less
than 200 dollars, simply because my first training 4 decades ago
as a teenager in a boatyard was in basic hand tool sharpening
and maintenance. Yes, the shoulder plane is relatively
expensive, but they are indispensable even for machine
woodworking and sound but scuffed ones like this Stanley 93
My point is that a newcomer’s first steps shouldn’t be making furniture for the house or that fancy dinghy, they should be acquiring and tuning the necessary tools and learning to use them in traditional construction of simple benches, shelves, assembly tables, horses and jigs for their first shop. Why traditional construction? Because study and practice with hand tools will teach you more about your material…wood…than machines will, and it never ceases to amaze me how little even some advanced craftsmen understand about their material. Hand tools allow you to feel how steel wants to move in cutting wood based on the grain of the wood and creates an understanding that applies to obtaining clean cuts using machine tools as well. It will pay off in the long run to your pocketbook, your enjoyment and your skills, as it’s easier on all to make those first irreversible mistakes slowly in 50 cents worth of maple than at breakneck speed in 80 dollars worth of mahogany. The
mortise should be cut first, and I’ll chop one with the chisel.
This is a long, millwright’s mortise chisel made by James Swan
almost a century ago. It’s not a “framing” or “firmer” chisel as
described by many tool dealers or collectors, it was
manufactured primarily to chop mortises in window, door and
millwork factories more than for tradesmen, who generally used
smaller “sash” mortise chisels more easily carried in a
carpenter’s box or shipwright’s chest. All mortise chisels come
in widths to match the intended mortise, but these millwright
chisels are much longer and easier to hold plumb, much heavier,
and combined with the right mallet, much more powerful. And with
power comes speed and efficiency. Just gander at the size and
cleanliness of the chips this beauty makes below.
…and use it to lay out both mortise and tenon on the squared-up stock. I darkened my lines with a pencil and drew some otherwise unneeded lines for clarity, but laying out your joints should be done with marking knife and awl, not a pencil. The knife used across the grain and the awl used with the grain is not only more precise, it provides accurate recesses to index chisel or saw, and as you will see, scribes the wood sufficiently to prevent unwanted splitting and chipping while cutting or chopping.
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can
still be had in the 60-dollar range. 3-tined adjustable mortise
gages along with the old Disston saws can be found used for less
than 20 dollars, and the large mortise chisel is a recent
acquisition as part of a salvage chisel lot and cost less than 5
dollars. 
