Starting Construction: Rough stock preparation

Since this is Sunday, I’ll start with the Woodworker’s Prayer:
“Oh Lord, so far today I’ve not cut myself nor anyone else. I’ve not coveted my neighbor’s tools, nor damaged any of mine. I’ve not been led into temptation to buy that 24″ Drum Sander that Norm uses on the New Yankee Workshop. I’ve not messed up any of my projects, nor had cause to take Your name in vain.
For these things I give thanks. But Lord, I’m gonna get out of bed soon, then I’ll need all the help you can offer. Amen.”

It’s a beautiful morning, and warm enough that I can open the garage door. Gotta love that. Doobie Brothers on the shop sterero, and Angus is here and ready to get started.

Stock Preparation

This mesquite is all rough lumber, and has to be squared – its faces made flat and parallel, and the edges (or one edge, to start) made perpendicular. I started by rough cutting the boards into their approximate length on the miter saw (plus 2-3 inches for error). That makes them easier to handle in the jointer, which is a short-bed benchtop jointer. It’s one of several compromises I make due to space limitations, but it works well enough for everything except the very largest projects.

I noticed some things about mesquite lumber right away. For one thing, pencil marks vanish completely. Marking these boards (particularly in the rough state) has to be with a white crayon pencil. It’s heavy. It’s heavier than either walnut or rock maple, and might be up there with rosewood (which I don’t use except for very small things; it’s non-renewable, and frighteningly expensive). And it smells different. Oak, walnut, maple, cherry… each wood has a distinctive odor when cut. Mesquite is different yet again, and not at all unpleasant. Also, there are checks (cracks) in the ends of a couple of boards that should be trimmed off to prevent splitting later.

The concave faces of the boards will become the top of the table, and go DOWN through the jointer.

After trimming to length, the next step is to run the boards face down through the jointer, to flatten the first working face of the wood. Boards go through with the grain of the wood down in a concave pattern – wood tends to cup in that direction, and you don’t want the stock rocking back and forth on the jointer table. Also, the concave faces will become the top of the table, to minimize bowing due to changes in the moisture content of the wood. Cutting is in the direction which orients the climb of the grain downward and towards the back of the jointer: in other words, the slope of the grain is down and to the right, if viewed from the side. That helps prevent tearout caused when the leading edge of the grain hits the cutter knives of the jointer. It isn’t always possible, but it’s a good idea to orient boards in that direction for most cutting operations.

Before starting the jointer, I check to make sure the fence is perpendicular to the table. It doesn’t really matter for this first cut, but it’s a good habit to form. This fence never seems to be quite as tight as I’d prefer, so I’ve learned to be careful about it.

The boards are fed slowly through the jointer, until the first face of each board is flat. The keyword here is slowly; I tend to rush the process if I’m not careful. Truthfully, this isn’t my favorite part of woodworking, and I have to force myself to be patient.

Once flat, the boards go through the planer. This brings the second face flat and parallel with the first one. If you don’t flatten the first face on the jointer – and just start by running them through the planer – then it will parallel to the first face, but not necessarily flat. The rollers will follow the rise and fall of the surface of the wood, and you can wind up with boards shaped like barrel staves. True to each opposite face, but not flat.

The new planer (see previous post) performs beautifully – no measurable snipe. Also, the repairs on the dust collection system greatly improved the amount of mess left by the planer. This is a noisy, dirty, time-consuming operation. Exactly the sort of thing that makes me prefer hand tools for most work. But flattening boards by hand is tremendously exacting and labor- and time-intensive. Machining boards to dimensions is much, much quicker, but it requires both a dust mask and hearing protection. Noise levels with the dust collector and planer running can approach 120db.

This process is where the beauty of the wood starts to show. Rough mesquite doesn’t look like much. Once planed, the grain and incredible complexity of the surface starts to really glow. It’s not a smooth, even-grained wood like long-leaf pine or clear maple. It has lots of turns in the grain, voids, and amazing color differences.

Before and after planing.

Once the faces are ready, the boards go back through the jointer on edge, to trim one edge square to the faces. Then the remaining edge is trimmed off on the table saw. I do not recommend you ever run stock through the table saw with a rough edge against the fence… that can be terribly unsafe, as the rough edge can allow the stock to shift against the blade and kick back. The only injury I’ve ever had in the shop was a small kickback, it gave me a nasty little cut on my hand, and it scared the holy hell out of me. Which is one of the main reasons I’m so adamant on the subject of shop safety.

Starting the top

Now that the boards are ready, it’s time to start the table top. This is a fairly simple procedure, but I always agonize over what orientation of boards will look best. There’s a million “rules”, but it all comes down to taste in the long run. It is, however, a decision that will greatly influence the overall look of the piece. Once I’ve decided, I mark the boards with a carpenter’s triangle so I don’t get them mixed up later.

The boards are aligned, and checked to make sure the jointed edges are square. One set of adjoining edges doesn’t quite meet properly; probably due to a hiccup or something while jointing. I clamp the two edges together in the bench vise, and give a couple of passes with my jointer plane, and then they meet perfectly. It doesn’t even matter if the two edges begin to pick up a tiny slant by hand-jointing them, because since they face each other in the vise, any error translates to both boards equally. I’ve jointed fairly long boards for tabletops by hand this way, and it’s always worked perfectly.

I get out the biscuit jointer and cut biscuit slots in two places on each edge of each board. It should be noted that the biscuits here do not add strength to the joint. In fact, the glueup doesn’t even really require clamps: you can simply edge-glue long boards together quite nicely, and it’ll be perfectly strong. But I want to make sure there’s no slippage, so the biscuits will serve to keep the boards aligned while being clamped.

Once the slots are cut, I dry-fit the whole assembly before gluing it up. Making sure that it all fits before gluing it is a lesson I learned the hard way (like most of us). Then I knock the joint apart, glue it up, and tighten the clamps.

Once clamped, glue squeeze-out appears along the joints. After about half an hour, get a dull chisel or scraper and clean the excess glue off as it gets rubbery.

Gluing up the blanks for the legs is next. It’s a simpler glue-up; the two boards that make the blank are face-glued to each other. Blue painter’s tape is run along one edge to help keep them aligned as I put them into the clamps. I have a fairly limited amount of clamps, so I’ll have to do the blanks one at a time.

That’s it for today. A decent day’s work.

Dovetail Report: I think I’m over the hurdle of not being able to get the cuts for the tails started. I was putting too much downward pressure on the saw, and my stance was wrong. I was also practicing in hard ash; the drawers of the table will be soft maple. That makes for much easier going. The two sets I cut today are starting to show real improvement.

Next time: Another side trip, and considering angles.

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