More shed time today, and I spent the first half of it fettling the middle shelf in the desk. Straightforward, if repetitive process – assemble, check what’s too tight and what’s too loose, cut or pare the shelf a little narrower with saw and chisel, reassemble, recheck, repeat until the dovetail joint that was horribly stressed by the shelf being too wide:
…is no longer stressed, but just snug:
And doublecheck all the other joints to be sure nothing else is opening up.
Okay, I’m happy with that.
I’m also happy because before assembling this, I marked out the back of the top of the sides to show which bits had to be cut off to give a straight line across the back (because the top goes up against the wall for support), and when I assembled it:
Nice straight line.
So, now time to get rid of all the straight lines! Out with the French curves and the compass.
And also did a bit of marking with pencil of various things to know what goes where when assembled. Then I broke it all down and spent some time with the bandsaw, various handsaws, chisels and my favorite spokeshave to shape the shelves.
Not done yet, but nearly there for the walnut desk, and a little behind that for the middle shelf. Once they’re done, it’ll be time for inlay and decorative stuff. I need to order some resin for that, and do some testing. And there’s be the light fitting and cable chasing and then finishing and then final assembly and that’ll be that.
Meanwhile, there’s another project I want to start on because I’ve been watching Ron Aylor’s latest bout of carving recently and I’ve been wanting to go do some. But that will require some oak to be prepped. I have some but…
Well, I’ll have to dig it out…
…with a JCB. Le sigh. Also, it’s a bit thick for the size of box I have in mind. Time for the DeWalt 734 to earn it’s pay…
I’m kindof shocked really. I pulled four boards (because why dig that much for just one?) and with the #05 got one face to sit flat on the bench. That took about 25 minutes in total.
Then I fed all four through the 734, dropping thickness by about 0.4-0.5mm on each pass, and alternating sides once the first uppermost side was flat. That took 20 minutes to give the boards above. That would normally have taken all of this week’s evenings with the scrub plane. That’s a massive boon, I think it’s obvious the 734 is going nowhere. I mean, it’s not my idea of a finish planing, it’s very rough milling but still. That’s damn useful.
Now, I want them a few mm thinner, but it was getting late and the 734’s noisy, so I’m leaving them to warp and cup overnight before doing the last few passes in the 734. And also, I think I need to (a) clean up and (b) sort out something about extraction…
Some more – increasingly rare – time in the shed over the last week or so, and I started cutting the top shelf for the desk.
While I had the desk assembled to this stage the last day, I scribed the top shelf angles with pencil and set the board aside. Then this week, after thinking about it a bit, I double-checked the angles of the sides of the walnut board – because it’s the core around which all this is built – and then I used the angles of the walnut board, and the width from the scribe marks (and yes, I double-checked that the sides were plumb to the desk before scribing), and used those two to cut the top shelf.
I didn’t cut them according to the scribe marks’ angles because there’s a little bit of twist in the sides (not much, maybe 4-5mm over the full length of the sides, and the sides are poplar, not oak) so the top shelf should be pulling them back to the walnut board’s angles, not locking in their twist.
And of course, because it’s an angled cut on the end of the board, the dovetails get interesting.
The angles that would work on a straight edge obviously do not work on an angled edge because the line of the grain is no longer at right angles to the end – if you just cut the dovetails with no change to the angles, you’d get all manner of issues with the look of the joint, and with its mechanical strength due to some horrible short grain issues. So, like with everything, there’s a complex way to do it where you do all sorts of maths to figure out what the angles should be, or, there’s a trick (actually, there are two tricks, but one involves spending a few hundred euro on a Bridge City Toolworks bevel and sod that for a lark).
The sane trick is that you keep the offcut from the board when you cut the angled edge, then you mark off the dovetails with a normal dovetail marker against the straight edge on the offcut and you put a bevel against the angled edge and set it to the angle you marked off on the straight edge.
You also don’t cut both sides to the same angle – one side (in my case) is a 1:6 slope and the other side is a 1:8 slope. It doesn’t look right otherwise because of the angles.
I marked off the spacings using the normal two-dividers approach though.
With the marking out done, the sawing is nothing fancy (you can’t use guides, you have to saw to the line by hand – but that’s not that hard so long as you take your time).
Some tidying up with chisels and that’s the board ready. Next, hold it in place on the top of the relevant side, misalign it, swear a lot, erase pencil marks and retry until you eventually manage to hold a two-foot-plus board at a perfect right angle to an edge that’s five feet up in the air while drawing around it with a pencil. I mean, it’s doable, but you learn new swear words.
After getting the transfer of lines done, the rest is standard dovetail fare. Cut them, fettle a lot with chisels, swear at gaps, the usual dance. And then repeat for the other side.
At that point, I assembled the carcass and found that the left dovetail fitted fine, and the right dovetail was hanging in mid-air an inch clear of the right side of the desk. What the…
Turns out, the middle shelf was too wide by a few mm. Out with the #04 and I shaved down the width by 2mm on each side (not all at once, it was a pare-and-fit job) and eventually I could assemble the entire carcass.
That middle shelf is not done yet though; it’s still a few mm too wide at the back, while being about right at the front but the end result is that there’s a lot of stress on the right hand dovetail joint:
There’s a whole 2.4mm of a gap there at the bottom, purely because the shelf is spreading the sides (I assembled without the middle shelf – it went together perfect square and true). I have some more fettling to do there tomorrow. But that wasn’t the point of this assembly (or bringing it indoors for that matter), it was more to check sizes. That desk seems so low off the ground that there’s no way it’s right, right?
Nah, it’s grand, the client is happy.
It’s now all back in the shed with the middle shelf removed. Tomorrow I’ll work on fettling that middle shelf fit and when that’s good enough, I’ll take the desk all apart and begin work on inlays and decoration and shaping. The inlay won’t be entirely conservative – the client isn’t a huge fan of traditional marquetry because he can’t spell “traditional marquetry” yet, but an inlaid race track for cars would be cool, and an inlaid blue ocean on which to recreate the death of several hundred people in the freezing waters of the north atlantic would be a very desirable feature apparently. I don’t know, don’t ask.
I also want to cut a 7mmx13mm channel in the underside of the middle shelf – that’ll house an LED strip in an recessed aluminium channel with diffuser (ebay’s a great tool these days). That does mean I need to figure out a way to run a mains cable from that shelf to the ground, in a way that doesn’t lead to a seven-year-old finding a way to pull it out of the desk and strangle the cat with it. Anyone know of a neat way to chase a cable through a piece of wooden furniture over a distance of around five feet in total? No, cable clips are not okay, and just routing out a channel and epoxying the cable in seems somewhat unmaintainable…
Speaking of routing, for some of the resin and the LED channel, I thought I might go back to the beast and try that again, but this time with a better way to hang on to it.
For the rectangular channel for the LEDs, a chisel would be just as good really, but for irregular pools of freezing-cold-north-atlantic-ocean blue resin, the router does make life a little easier.
Speaking of, I need to experiment a little with the resin. I have some ideas…
So the last time I worked on the desk wasn’t as far back as October, but I didn’t get a chance to write it up (work has been a tad busy and other stuff has also been eating time). But with xmas dinner done, holidays finally kicked in for me and after collapsing for a few fallow days, I got back out to the shed in the last day or so. And managed to avoid breaking my neck on the decking outside the shed as well (some anti-moss napalm has been deployed and I’ll have to repaint that decking with some sort of high-traction paint before any really cold weather hits I think, and possibly drill a few sneaky drainage holes against standing water).
So in previous days, I got the dovetail mortice cut on the sides, using my normal technique for a stopped dado joint, which is to chop a small mortice at the point where the dado stops (so the saw has somewhere to go, though I wonder if a stair saw would solve that). It’s a bit complicated here by the line of the grain not lining up with the dado angle very well, but it wasn’t unmanageable. Then out with the ryoba and very carefully sawing down the edges of the dado. Cutting on the pull here helps a lot, but the japanese saws not really wanting to track on a flat surface doesn’t (western saws I think would be happier as they have thicker plates, but all of mine hate me and won’t work for me at all). So in this case I chopped along the line with a chisel and cut a little knife wall to help guide the saw, then sawed down to depth once the cut was deep enough to let the saw blade track.
With the edges cut down to depth, out comes the chisel and I hog out the bulk of the waste pretty quickly, then switch to the router for the last one or two millimetres of depth. Not the powered one, the one that actually likes me.
Then just repeat that for the other side, being sure to mirror image rather than carbon copy…
This project is right out at the size limit for my shed by the way, if not well past it…
So now I had two dados cut, both of which are as narrow as the minimum width of the dovetail (the bit at the shoulder where the joint is thinnest), so now I had to remove the last bit of waste to form the dovetail. However, after watching some of The Woodwright’s Shop (one of PBS’s gems) I thought I’d just make one side of the dado into a dovetail instead of both. I mean, if it works for Roy…
So, I clamp a straightedge in place to both hold the side and give the router something to run against, fit the dovetail bit, don all the PPE, triplecheck where my fingers are, and I fire it up and make the cut.
And it didn’t come out too terribly. I mean, it’s not pretty, but there’s a noticeable lack of severed and mangled body parts in the cut, which I’m a fan of.
Okay, so just repeat for the other side and…
…promptly forget which way the blade is spinning and that this is a mirror not a carbon copy, and that I’m now climb cutting without being ready for it and the fecking thing actually jumps for my face.
Enough with routers, I say. Stupid things. Anyway. It’s done. The joint mortices are cut. And feck setting up a router table to cut the male part of the joint, I’m done with that sodding tool for now. And in fact, that was the last time I got to work in the shed from then until this week, which is when the rest of this all happened.
Right, so I have to cut the edges of this now to let it be driven into the sides with the male part of that dovetail joint, but it also has to protrude out the back far enough to almost reach the wall it’s leaning against. So there was a bit of footering about to get measurements and scribe lines and so on, but finally I got that sorted.
Next up, cutting the dovetail part of the joint. I measured the router bit’s angle, set a bevel to that angle, then planed a scrap offcut from shaping the sides so that its edge matched that angle relative to a face.
And now I had a paring guide for a chisel. Next I pared out the dovetail along the joint.
The back end of the paring guide is up off the bench, with pressure from my index finger holding the angled edge flat against the edge of the desk, which puts the face of the paring guide at the right angle; then I slowly pare away, nibbling at the cut on the second pass, which is when I put a shim under one side of the desk so as to angle the board and thus give me a sliding stopped dovetail joint.
You can see, with the shim under one side (and the other side held down by holdfast), the paring block naturally carves a sliding dovetail shape.
And then I did a test fit and of course it didn’t fit at all 😀 So I trimmed the vertical edge of the dado a few times and eventually got a nice solid fit. And then repeated the process on the other side.
It’s not perfect, I’ve not done this kind of joint before but it works.
Self-supporting! And also way too big for my shed 🙁
Barely fits. Also, the joints are not yet driven all the way home there. It’s a solid fit, but it’s a little tight still (I have yet to finish plane the sides or the desk and I expect that to loosen things a little). And I have to scribe the angles for the top shelf yet, which will be dovetailed in because I hate myself.
Scribing it won’t be a major hassle. Cutting the dovetails while the joints are loose however, isn’t a great idea because the shoulder to shoulder distance varies as the joints get driven home. I might well cut one side’s dovetails, leave the bevel set for the other side and not cut that until closer to final assembly which will be a tad finicky but less so than trying to cut both and then undoing the joints, I suspect. Or maybe I’m wrong about that.
Either way, I suspect the bigger issue is going to be space to work…
And to think I was pondering putting a lathe in here. I mean, I still am (I got a lot of woodworking gift vouchers for The Carpentry Store over the solstice) but I have no idea how I’d get it in there without freeing up a lot of space (and one of those vouchers was for The Timber Yard so there’s even more timber to go in there soon as well).