Graduation Day – and new lessons

“I love it when a plan comes together.”

–Hannibal Smith, The A-Team

I started out in woodworking with power tools.  Since then, I’ve been working my way backwards… slowly incorporating more hand tools into the process.  I find it relaxing, often more precise, and producing (if not better) somewhat different results.  A year or so ago, I took Howard Hale’s excellent Hand-Cut Dovetails class at our local Woodcraft.  One of the things he said that stuck in my mind was, yes: machine-cut dovetails are easier, and more precise. They usually take as long (or longer) to do, because of the machine setup required. Machine-cut dovetails will look exactly like they’re from any piece of nice furniture from Haverty’s. Yes, hand-cut dovetails will be slightly irregular by comparison. It will clearly be hand work. And that’s why it costs five times as much.

I realized when I started today (the first of two full back-to-back days in the shop, which is an incredible luxury for me – thanks, Cathrine!) that I had miscut the back apron.  I made one of the first mistakes in furniture making, and one that I’ve written about in the past.  I measured something.

Today’s Lesson #1: Not a new one, but worth reiterating. Don’t measure stuff. Just don’t. Mark the pieces from each other after the first one is cut.

The distance between the tenons for the back apron was off from the front and back stretchers by about 1/8″.  There was nothing to do but remake the piece, or lengthen the tenons on everything else. Much easier to recut just the one.  The hitch was that when I thicknessed all the parts, I didn’t leave any extra – and that meant changing machine setups in my small shop (again).

Today’s Lesson #2: When you’re thicknessing lumber from raw stock, do extra.

I had a piece of stock about the right size – an inch or two big in all dimensions – and flat on one side. I could move the dust collector hose, reset the planer to the right thickness, plane it flat, move to the miter saw, cut it to length, change the dust collector gates to the table saw, cut it to width, switch the dust collector gates to the jointer, and joint the edge.

Instead – without thinking, this time – I cut it to width with a small joinery saw and a bench hook, ripsawed it to width with a bowsaw, planed it flat, and squared the edges with my Veritas edge-trimming plane. Elapsed time: 8 minutes. No noise,  no hoses to move. It didn’t run Angus out of the shop because of the racket. No stress.  No mess. Just some curls and shavings. Then I realized that I had just done this process without thinking about it… I had moved from power-tools first to hand-tools first for this (admittedly simple) operation.  For me, that was Graduation Day.

To avoid repeating this same error, I marked the tenons on the front drawer rail directly from the front lower rail.  I aligned the two pieces in a bench ho0k to do the marking, and then marked and cut the tenons for the new back apron in the same way. This led to…

Today’s Lesson #3: Bench hooks aren’t just for sawing. They’re perfect for bracing your work for almost any reason – like making clean, straight layout lines.  Much better than either clamping work in a vise, which tends to put things at uncomfortable visual angles, or (worse yet) juggling them around in the air or braced against your body.

Once the back apron was finished, it was time to cut the curves in the front and back rails.  On this one, I decided to cheat, and go back to power tools.  I was originally going to try to cut the curves by hand with a coping saw.  The blade on my bowsaw is too wide to cut these curves, and I didn’t really have another hand tool that would work well for this. Lots of stuff for cutting joinery, less for cutting curves.  But due to the hardness of the wood, and the need for some accuracy here, I cut the curves on the band saw instead.  I marked the line with the curved edge of a serving platter we had in the house, made the cuts, and cleaned them up with a small spokeshave and a piece of 120-grit adhesive sandpaper attached to one of the cutoff pieces.

Then the plan started to come together: I assembled the front and back sections. I scraped and sanded everything first, and knocked down the sharp edges with a block plane and a piece of sandpaper. The simple card scraper is still the best finishing tool ever invented.  I don’t remember where I read this… but if you put a refrigerator magnet on the scraper, it’ll stop a lot of the heat transfer to your thumbs, and make its use a lot more comfortable.

It was a pretty simple glueup, and came out straight the first time.  The tenons mated well, except in one place in the back I found (too late) to have a misaligned shoulder that’s going to take some repair when I’m finished.

This was working well… and was time to move to a more difficult piece: the lower stretcher.

The through tenons are fairly simple pieces; the challenge is that the shoulders of the tenons have to match the 3 1/2 degree angle of the front and back legs where they meet the rails.  The problem is that there’s no way to calculate the dimensions of the distance between the tenons, due to the angle of the front and back legs.  The distance between the lower ends of the stretcher and between the upper ends is different… and this is a pretty critical measurement.  And there’s no way to test it except to assemble it – and you can’t until both tenons are cut. At first, I thought I’d have to cut the shoulders too long, and trim to fit – and the though of that in this hard mesquite gave me the cold shudders.

The answer was to violate lesson #1: go ahead and measure it. I dry-fitted the leg sections and the side rails together without the stretcher, and then used a steel rule to measure the distance between the upper edge of the mortises in the lower rails. I started the measurement at the 1″ mark in the back (to make it easier to align the ruler), measured it at 19 9/16″, and subtracted the 1″ offset from the other end (don’t forget that! It’s easy to forget.), so the distance between the upper edge of the tenons is 18 9/16″.  Once the angle is transferred to the sides, the lower edges will line up correctly. I knocked the assembly apart again.  And yes, you’re correct: in the photo, you can see a small tearout at one end of the mortise – but it’s going to be inside the shoulder of the tenon, and completely hidden by it.

I marked the tenons the correct distance apart for the top side, and then marked the sides of the tenons outward with the same angle jig I made when I started the project. Then I carried the line across the bottom at the base of the new angle.  I’ve found the easiest way to do that is to put the edge of a marking knife in the cut, and slide a square up against it to position it for the marking. I chiseled out the edge of the tenons first (see my previous post), and used the jig to align the saw prior to starting the cuts.

Today’s Lesson #4: Don’t Panic. Lots of mishaps are repairable, and will be absolutely fine with a little extra work.

If you don’t have the book Fixing and Avoiding Woodworking Mistakes, by Szandor Nagyszalanczy, I highly recommend it.  it’s where I learned the basis of what saved me today.

I had cut the stretcher tenons slightly oversized, so I could trim them to fit tightly into the mortises on the rails. As I was cleaning up the edges of the tenons on the with a chisel, I knocked a large chip out of one of the tenons. Of course, I could have just glued it back in place – but it flew off into a big pile of dust and shavings, and I never did find it. It could also have shattered, but was unrecoverable, in any case.  There were two causes of this mishap:

1) the tenon is an area of wild, turning grain.

2) I got careless.

This wasn’t just a little ding that can be filled, or a tearout in a place that’s hidden behind a tenon shoulder: it was the outside part of the front through-tenon on the stretcher. The answer was to cut it out slightly further until the sides were square, glue in a small diagonal piece of square scrap with cyanoacrylate glue, and trim it even with a block plane. Once the finish is applied, I think even I will be very hard pressed to find it.

The project instructions state that the author thought the best way to cut the holes in the tenons is with a “single stroke” of a hollow-chisel mortiser. I agree; it’s the right tool, and worked beautifully. But “single stroke” means he was working with oak, not mesquite. It took somewhat more than that, but did an excellent job. I reassembled the pieces, marked the edges where the holes should start, and then shifted both holes inward slightly, so that the pegs will pull the rails tight against the stretcher. The pins were cut out of a piece of scrap, and shaved to the correct angle with a block plane.

I knocked it all down again, assembled it with the pegs and checked the fit, and then knocked it apart for the last time. The clamps have to pull the angled frame tight, so I took a minute and cut some scrap to the correct angle and attached adhesive sandpaper along the angled face, to use as clamping blocks. I brushed glue on the tenons on the upper aprons, and assembled the frame. Five pieces this time: the upper rails, the stretcher, and the front and back leg assemblies. The blocks keep the clamps pulling straight across the angled frame.

I checked the diagonal distances to make sure it was square (it was) and set it aside. While the assembly was drying, I turned my attention to a couple of other things.

My first attempt at making the copper/resin filler for the voids was unsuccessful.  It came out kind of a dirty brown.  This time, I tried the same thing with a much higher proportion of powdered copper. It seems to have worked much better; the surface of the fill is almost iridescent. The epoxy is terribly slow to dry – it takes about 6 hours to lose its tack, and at least two full days to set completely.  I’m going to try a couple of more mixtures with some 5-minute epoxy, in hopes of not having to wait two days to see if it’s going to work or not.

Next was the frame that supports the drawer. It’s poplar, which is like handling balsa wood after the hardness of the mesquite.  The original plans called for the frame to be joined together with mortise and tenons. But honestly, I think that’s overkill.  It’s not supporting much weight, and was an added degree of complexity that doesn’t add anything much to the project. So my inner frame is half-lap joinery – essentially, two facing one-sided tenons, glued into an overlap at the corners. This photo shows it set into place, but it hasn’t been glued in yet – I’m going to hold off until the drawer construction is finished.

Before taking the framework out of the clamps, I tapped the pegs into place, marked them 3/4″ above and below the tenons, and trimmed them to fit. Then I tapped them back in, and took the assembly out of the clamps.

It’s starting to look like it might be a table when it grows up.

From here, the next major step is to build the drawer.  That means actually cutting the dovetails I’ve been practicing for real (no, I’m not at all nervous about it, why do you ask?). Then mount the drawer frame and rails, make the knob, and finish the top.

Meanwhile, Angus says the shop is a huge mess, and I need to stop and clean it up. Who am I to argue?

What a great weekend.

Next time: The Drawer Joinery.

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