Sunday, January 23, 2011

Joints

Author's Note: If you haven't had a cup of coffee for an hour or two you might want to get one now. Things are about to get confusing.

Earlier in the week I was talking about jointing which, you'll remember, does not mean "making a joint" but, rather, making a side or edge of a board perfectly flat, usually (but not always) in preparation for joining it to another board. The next step in the process, logically enough I suppose, is actually making a joint.

Having come of age in the late sixties, I have rather fond, pleasantly hazy memories of hanging out in a few joints, and rolling a few joints - but mostly without expert instruction and never with names as colorful as lap, dovetail (through or half-blind), or mortise and tenon, all of which have now been added to my woodworking vocabulary (if not yet my skill set), along with dado, rabbet (sometimes called rebate), fillets and plowing. We will be employing a number of such joints in our next project: building a small bench or stool, which we must also design ourselves. ("A plethora of benches and stools," as Tim said.)

After a brief, fascinating digression into the Fibonacci Series (don't ask), we begin by considering the different ways to join wood - namely with fasteners (like screws or nails), glue, or mechanical joints - and the various merits of each. Our focus is on mechanical joints, which we will make at first using hand tools, and later with the big power tools over on the Dark Side.

Precision Sawing
In order to make a good mechanical joint, we must learn to fit the pieces snugly enough so that glue (if used) will be able to do its job, or the shape and tightness of the joint itself will hold the pieces together, as in Japanese-style joinery. This necessitates a degree of precision in sawing and chisel work that seems unattainable by the average human. Nevertheless, in very little time, Jim demonstrates accurate marking - with a sharp knife, a marking gauge and pencil - and saws right to the line, leaving only a thin shaving or two to remove by using the plane on edge on the shooting board. We practice with our dovetail saws as well as the Japanese ones until we can make an accurate, straight cut. Did I mention that Japanese style saws cut on the pull stroke while western ones cut on the push? (Jim says this is because westerners are so pushy.)

Lap Joints
Tim takes over the demonstration of the full lap joint, which is used to join two boards intersecting on their flat sides usually at right angles to one another. It requires cutting notches in each board that are exactly the depth of half the thickness of the corresponding board and just wide enough to allow the corresponding slot to fit into the corresponding slot without enough space left over to stick a piece of paper in between. The sides of the notch can be cut using the precision sawing technique we have just observed. But the bottom must be done with a chisel and made as smooth and true as the face of the notch that will nestle against it. Ridiculous.

Here is Tim chiseling out the center of the first notch.

And making the cut more precise.

And doing the final paring with the chisel.


At my own workbench I spend an inordinate amount of time sawing and chiseling and chiseling some more. While I am definitely appreciating the micro-bevel on my newly sharpened 3/4-inch chisel, and sort of getting it to behave, I have a lot of trouble avoiding paring away too much wood. Despite my attempts to mimic exactly Jim's and Tim's technique, little bits keep tearing out at the end of the stroke, creating ugly divots where there should be nothing but silky smoothness, and causing me to mutter out loud words that I have valiantly been repressing  in here - so far. By the end of the day I have not only not finished the half-lap and full lap joints we have been practicing, I have yet to put a coat of shellac on my winding sticks, or sand and put the second coat of shellac on my straightedge. I think of something Tim mentioned a day or two ago: that we should keep in mind "appropriate accuracy" - that is, be aware of the degree of accuracy that is appropriate to the job - and perhaps this is good enough for where I'm at right now. Still, at this rate, if I were trying to earn a living as a woodworker, I would be starving.

I am including these photos of my first joints, only in the hope that by the end of the 12-week course I will be able to show you examples that are truly good enough that you will be able to tell the difference.

The full lap joint.

The half lap, or fillet, joint, with Jim's (Whittaker's) handmade mallet.


* * * * * * * * * * * * * * * * * * * * * *
A Plethora of Benches and Stools
In between working on our various practice projects, we have begun contemplating the design of our bench or stool. It is to be made from no more than four boards, joined at right angles, using at least two of the more complex joints we are learning this week - such as dovetails or mortise and tenon. I decide early on to make a small step stool, as I need one in the kitchen to reach the high shelves. Also, our house is fairly small and already crowded with furniture, so I can't bring in anything new unless it has a place to live; I have a spot in mind where I could tuck a small stool under an antique table where it will be handy.

But by Tuesday afternoon I am feeling overwhelmed and discouraged. In a week or so we will have to complete this project, with more complex joints, a lot of decision making, fitting and finishing. Jim and Tim have brought in samples of some of the pieces they have made for this type of exercise. They are beautiful. And intimidating. Given the amount of time it took me to half-make a couple of simple joints, badly, I cannot see how I will be able to get it done.

Tim asks us to make some quick sketches of ideas - nothing fancy or finished. My brain is full of concrete and the ideas do not come. I have, with a certain amount of self-discipline over the years, taught myself to step back and not worry when I feel this way - I know the ideas WILL come. Eventually. But often it takes sleeping on it, or doing something else for awhile. I doodle with my pencil, getting nowhere. Presently, we share our sketches with the class and gently critique them. Some are truly inspired.

With the help of my classmates' feedback, the mental concrete cracks a bit and I make some progress. We are to work on our design at home and be ready to make a full-size mock-up out of cardboard the next day. Tim also wants us to do at least eight more quick sketches.

Perhaps it is the glass of wine I have with dinner; I manage to work out a few of the kinks in my design and go to bed having completly forgotten about the eight quick sketches, but at least satisfied that the cardboard mock-up will work. Somewhere around 2:00 a.m. I wake up and remember the eight sketches. Shit. But as I drift back to sleep, a silly idea pops into my head and I start to smile. In the morning as my coffee is brewing, I grab a piece of paper and quickly sketch out eight silly little benches and stools before the first cup of coffee is poured.

We spend the morning building cardboard mock-ups. Here I am with mine. (Notice I am wearing my first pair of Carhartts and my favorite Wooden Boat Festival T-shirt!)


By lunch time the rain has stopped, the sun is shining and we line up our gorgeous creations on the stoop for a group photo.

L to R: Justin, me, Alex, Melanya, Kia, Mark. (Note: Melanya arrived at the beginning of this week, having driven from Kentucky last week. She already has considerable woodworking experience- she spent two years at the Northwest School of Wooden Boatbuilding, first as an intern and then as a full-time student.

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