Jigs on the Table

The blocks for the legs are now complete.  Rough glueup size is 1 3/4″ x 2″. The blocks have to be brought square and milled to final size (1 5/8″ x 1 7/8″). The procedure is the same as for squaring the lumber: square two adjacent sides on the jointer, then plane the other two flat.  After that, the legs are cut to their rough length.

Now on to two simple jigs, that will make the whole project proceed more smoothly.

The Angle Jig

A lot of cuts for this project are at an angle – about 3 1/2 degrees.  This includes the side rails, the drawer front, and the ends of the legs.  They don’t have to be exactly 3 1/2 degrees, but they do all have to be the same.

Trying to measure an angle like that repeatedly and accurately is a virtual impossibility in this kind of work. But it’s simple to cut a layout jig to mark the pieces and guide the cuts.

The jig is a simple t-shaped block, made out of two pieces of 3/4″ plywood.  They’re glued together and tacked with a pin nailer into a t-section about 8″ long. Then, the jig is laid on the miter saw, and the saw set to 3 1/2″.  The center rail of the jig is supported on a block so it doesn’t shift. First one end of the jig is cut off, then the piece is flipped and the other end cut at the same setting.  That ensures that both ends of the jig are cut to the same angle. The two blocks are aligned in miter clamps (see photo) to keep them square during glueup.

Once built, always double-check the accuracy of a jig – remember, any errors in it will transfer to the project every time it’s used. In this case, the easiest way to check is to use one end of the jig to mark a line on a board, flip the jig to the other end, and mark another line adjacent to it. If both ends of the jig are the same, the lines should be parallel.  This one seems fine, and this jig will be used to mark and lay out every cut made at this angle through the project. The angle of the jig is written on the side – jigs never get thrown away, they go into storage in case I make another piece of the same furniture sometime (that’s a lesson learned the hard way).

The Dovetail Jig

I’ve had a couple of problems laying out dovetails. One is that I tend to overcut the layout lines slightly, and the other is in aligning the blocks to mark out the tails.  The blocks tend to slip around when marking, which can make the lines inaccurate.  And yes, I cut pins first – otherwise, I find it difficult to follow the line for the pins across the endgrain of the pin board. That’s a loooong argument, and there’s enough on the internet written about it to fill several books.

I think one simple alignment jig may solve both problems. The jig is two small blocks of rock maple out of the scrap bucket, about 6″ long. Holes are drilled in both ends with a 3/8″ forstner bit.  Drilling is done with each piece clamped against the fence of the drill press, to keep the holes in the same locations.  Then a 1/4″ threaded sleeve is hammered into the holes on one block, and two pieces of 1/4″ threaded rod is added.  Nuts are screwed onto the rods and tightened against the backplate, and a couple of drops of superglue are added to each to lock the nuts in place.  Then the other block is placed on the rods, and threaded knobs screwed on.

That’s a fancy way to say “the two blocks make a little sandwich that you can tighten around the workpiece”.  The blocks are slipped over the workpiece (it’ll handle pieces up to about 3/4″ thick”, aligned with the layout lines, and tightened down.  When the cuts for the pins are made, the saw will hit the stop when it reaches the layout lines.

It will also allow me to brace the tail board against the pin board for marking out the tails, without having it slip around. Of course, the jig will eventually get scarred up, but it’s just a piece of scrap wood and about a dollar’s worth of hardware, and only took about 10 minutes to make. And if it saves me overcutting the dovetails on this project, then it was 10 minutes well spent.

Next: More project pieces, more work on the top, and (maybe) beginning joinery.

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Side Trip: Miter Saw Fence, and Back to the Top

This project (the Stickley table) is challenging in part because of the angles of the legs. They meet the top and sides at about a 3 1/2 degree angle. It doesn’t have to be an exact measurement, but it does have to be exactly the same on all four legs, and each leg has to match the sides. Most of the cuts will be made by hand, but there are a couple of things I’m going to do on the miter saw. One of them is to cut an angled guide for the handwork to insure its accuracy.

I’ve noticed recently that my miter saw (a Hitachi C10FSH 10″ sliding compound miter saw, actually) has fence problems. The right side of the fence is machined with a slight curvature. Not much, but enough that it’s caused me problems. As far as I can tell, the curvature is only there to allow the cutoff section to shift back and impact the blade, causing it to bind and launch itself at the operator. I don’t like that much.
Fortunately, it’s fairly easy to fix, and the fix will make use of the saw easier. I added a fence out of hard maple that bolts to the short aluminum fence that’s part of the saw. I added a 2′ piece of Kreg t-track to the top of the fence, to attach a stop to the left side – which is important for keeping multiple pieces to identical length. Measuring each one separately leads to error; bracing them against a hard stop keeps them exactly the same.
I had to limit the fence to a 2″ height – about an inch shorter than I wanted – to give clearance to attach the track. I also added a measuring tape to the top of the track. That was much trickier than I expected, because the measuring marker extends from the right side of the stop about half an inch, so the tape had to be offset to match. This whole arrangement makes it easy for me to cut pieces to length with reasonable accuracy, without having to individually measure each one.

Back to the Top

The top has been removed from clamps, and trimmed to its final dimensions. I have to admit, I’m really pleased about the way the grain in the top looks. There are two or three little black voids in the top, which is typical of mesquite. But that’s okay: because I intend to do something completely different from any of my previous work. I’m going to fill them with melted copper. 
Doing the top now allows me to work on it in conjunction with other parts of the project. It has to be scraped perfectly flat, sanded smooth, have the edges softened, and the voids filled.
Also, the other leg blanks are made and glued up. Next, they have to be trimmed to their final dimensions, and I can move on to other parts of the project.
Dovetail Report: I’ve gotten completely past my problems in getting the saw started, and I’m pretty well used to the new Veritas dovetail saw. The two sets I cut today fit the way I wanted with minimal paring. I also realized that it’s much cleaner to chop the wide part of the pins first; it minimizes the chance of damage to the pins when cutting the narrow side. I’ve also decided to make a small brace to use to set against the marking line, and to make sure the cuts for the tails are perpendicular. More on this later; I’ll post pictures of the jig when it’s done.
I also need to decide what kind of wood to use for the inside of the drawer. I think the maple used for the original table (which was made of oak) is a little light for the darker mesquite. I’m leaning towards sassafras, but I need to sand and finish a piece and see how it looks against the finished mesquite. I also need to do some of my dovetail practice in the wood I’m actually going to use for the drawer.

Next time: squaring the leg blanks, making the dovetail jig, and making the angle jig for the joinery.

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.

Side Trip, and a brush with disaster…

The holidays are past, lights and tree are back up in the attic, and I’m finally back to work. it’s easy to say that I have all the wood, plans, and tools, so all my ducks are in a row… but I suppose every journey has some side trips, doesn’t it?

First hurdle: For several years, I’ve had a Delta TP-305 planer.  It’s actually quite nice (it produces a very, very smooth surface, and blade changes are really slick), but it has a problem I never could get around.  It’s fine for most purposes, but it snipes. Snipe is a deeper cut on the ends of the board, which occurs when the board enters and leaves the feed rollers. All planers snipe to some degree, but when taking down boards for table tops or precision joinery, the amount of snipe from the Delta planer was deep enough that I had to cut about 3″ off each end of the boards to get rid of it.  The mesquite I’m using for the Stickley table is way too expensive to tolerate that; it ran about $14.00 per board foot.

The solution? New planer <sigh>.  It isn’t a purchase I had planned, but now that it’s done, I’m really glad I did it.  The new planer, a Dewalt DW734, has several features I like – including a 4-column carriage lock, that drastically reduces the movement against the feed rollers that causes snipe. The downside is weight: my old Delta planer weighed about 60 pounds, and the Dewalt comes in at about 90.  That means I can’t just store it below my workbench and place it on my assembly table when I need it.  It really needed a dedicated cart to keep my chiropractor happy. Taking care of the planer replacement had to come before I could proceed, as the first step is to dimension and square the boards.

My first inclination was to build the stand myself. There’s no shortage of plans for planer stands on the internet (and in my library). But really, it’s not the kind of work I want to be doing with my extremely precious shop time, and the only suitable material I have on hand is a sheet of expensive quartersawn oak plywood that I didn’ t want to waste on a tool stand. So I could have saved a little, but it would take up most of my weekend, and I’d still have to go buy materials. I settled on a Kobalt Universal Stand from Lowe’s, with a WoodRiver Adjustable Mobile Base from Woodcraft. I really, really like their mobile bases; the wheel locks are much easier to use and more solid than locking casters.  The planer itself is on a plywood subbase, because it’s about four inches wider than the Kobalt stand.

Second hurdle: My shop has a central dust collector, with conduits running down to all major areas, including connections for the table saw, band saw, belt sander, planer, jointer, sanding table, and workbench. The Jet DC-650RC dust collector itself (basically the biggest honkin’ canister vacuum cleaner you ever saw) is in the attic, directly over the garage.  It makes emptying bags kind of a pain, but I don’t lose any precious shop space, and I can keep it centrally located.

I love my dust collector.  Without it, the mess from the planer in particular is just unbelievable – it fills the whole place with chips. It makes shop work much, much more pleasant, and keeps cleanup time to a minimum.  The conduit is schedule 20 PVC pipe, with metal blast gates isolating the different arms.  The remote stays clipped to my shop apron, so it’s always at hand (and it reminds me to put my apron on).

The problem I’ve had is in sealing the joints. First, I used duct tape (of course), but it tended to come unstuck after a while. Then I switched to Gorilla Tape – brought to you by the makers of Gorilla Glue – and I was really disappointed.  At first, it made nice airtight joints, but in about seven or eight months, it lifted and peeled.  It also left a huge mess of adhesive. t was really the worst of both worlds: it was hard as hell to get off, but it still didn’t stick well enough to stop airflow around the joints. What appears to be a small leak can reduce airflow (and efficiency) tremendously.

The answer in this case – hopefully a permanent one, but we’ll see – was X-Treme Tape, available through Rockler.  It’s silicone tape, and non-adhesive; it adheres and fuses to itself.  It’s extremely stretchy, and conforms to the shape and contours of the joints. It seems to work very well, but it does not go as far as the ads say. The ad claims that a roll will seal about 15 4″ joints; I found it to go about half that far.

The near-disaster came late in the day.  I had retaped about half the joints in the conduits, and had disconnected the ground wire to replace some plastic elbow joints with a section of flex hose.  The system has a braided copper wire threaded through all the conduit, to ground out static discharges, and (theoretically) prevent flash fires in the dust.  Static is often caused by air passing over a non-conductor (like plastic conduit), and fine dust can be extremely flammable.   Everything was going well, when I leaned into the ladder, and accidentally hit the remote control switch for the dust collector (clipped to my apron, as always).

The result? The ground wire was sucked back into the pipe, and completely vanished.

I wound up having to cut the last two joints open and rethread the ground wire.  Could have been much, much worse… if the wire had been sucked all the way back up into the dust collector, it would have gotten caught up into the impeller fan, and I would have probably have been in the market for a new dust collector.  At the very least, I would have had to disassemble the entire thing – but it probably would have damaged the impeller badly, and might well have burned up the motor when it froze. As it was, I just lost some time (and expensive silicone tape).

Dovetail report: I’ve been cutting more practice dovetail joints, with mixed results. I changed saws, and have been working with a new toy: a Veritas dovetail saw. I found that part of the problem I’ve had starting cuts in end-grain is that I’ve been putting too much downward pressure on the saw, instead of letting the sharpness of the blade do the work.  Relaxing my hand seems to help that. I’ll keep practicing through this entire project, in hopes of having the drawers come out the way I want without wasting a lot of mesquite.

Tomorrow: I finally get back to the table, and start squaring and dimensioning the lumber.