Monthly Archives: October 2020

Daybed: Shaping the Platform

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All of that fussing around with making those clamps has finally gotten me ready to get started in earnest on my next project: a daybed/”couch”-like thing for an area of the house that currently has zero furniture. I had a sort of “vision” about how I wanted it to appear one day, and knew that I had to build it before someone else in the house bought one, because what I imagined seemed pretty neat, at least at the time. And when I read what Roubo had to say about them (yes, it’s in there), I became more convinced.

I wanted this to go a lot more quickly, but getting the large platform glued up took much longer than I had wanted–I had to make a whole bunch of stuff, including the clamps, before I could get to where I am now.

The first operation on the glued-up platform (after planing it off) was to shape it. I started with the ends, which are to be semicircular. I don’t have any trammel points to make a beam compass for such a large radius, so I just drove a couple of small nails into a board at the appropriate distance and used that to scribe it out:

As made, the radius of this improvised beam compass was a little too much, but to correct it, I just tapped one of the nails to bend it inward. I marked over the scribe line with a pencil.

Then there was a curve to lay out on the front. I guess I’ve been watching too much “Tally Ho,” because I tried to imitate Leo’s curve marking with a batten tacked into place:

I wasn’t sure if this would work, but it did. There were a few options for curve shape, mostly dealing with the tangent angle at the point of inflection in the middle. I chose a fairly mild one.

So I had one side done, and to do the other, I traced that side’s lines onto some of the paper that I use for making patterns, then cut along the lines on the paper, flipped it over, and transferred the lines to the other side of the platform.

Then it was time to start removing wood. I always get a little nervous the first time I cut into a panel (especially one that I’ve spent so much effort on gluing up), but it had to be done:

I removed as much as I could with a saw, working my way around the ends and trying to get as close as possible to the line. The cuts on the long grain were more challenging, so I used a drawknife to get rid of most of that material:

I finished the initial shaping with my Shinto saw rasp, and had this:

The front curve was somewhat tricky because it’s concave; I sawed a relief cut in the center and took out most of the waste with the drawknife and a chisel. (Note: Southern yellow pine is not particularly easy to use a drawknife on, but there’s worse.)

It came out as planned. Pay no attention to the ugly knots in the middle; those will not be visible with a cushion on top. I would have preferred clear wood, but due to multiple factors (the proximity of the nearest source of large southern yellow pine, the inconveniences of the source at the time that I went to buy it, not to mention the obnoxious process of picking through the pile alone on a steamy hot day in the middle of a pandemic), I settled for straight, mostly-quartersawn boards that would yield a clear perimeter, which is the only part of the wood that will be visible.

There isn’t much remaining work on the wood to do. I have to make the legs and the railing, do the final profile of the edge, and finish it. During finishing, I’ll make the cushion (hopefully I’ll have some sort of an idea about what I’m doing there).

Roubo-Style Panel Clamp Tweaks

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After I made my panel clamps, I’ve now used them several times and have been able to work around some of the issues that came up. Here’s a partial shot of the latest project getting its final glue-up (this is big–roughly 7×2 feet (2130x610mm) in area:

I have four clamps–three long ones and a shorter one that I made earlier as sort of a prototype. I used all of them on this project.

Let’s address the the two comments that on speculation of “stuff that might go wrong” that I got last time.

First, Lionel asked if glue squeeze-out is a problem; can you glue the work to the clamps? The answer is yes. I said that if this were a problem, I’d just wax the insides, and that’s exactly what I did. The wax eliminated the problem.

Then, Matt asked if I used a single wedge, would it tend to wear/dent stuff into the pegs? I tried it, and it does indeed mush into the pegs (especially when they are southern yellow pine).

On that note, I wasn’t terribly happy with the way that the single or double wedges were working. In particular, all sorts of things can happen when you try drive them in:

  • The force of the mallet blow can shift and tilt the entire clamp over just a bit.
  • On double wedges, it can be tricky to hit one wedge without loosening and dislodging the other wedge.
  • On double wedges, it’s pretty easy to hit them so that they go askew of each other, and then they can slip out.
  • If the clamps are too close together, it can be difficult to find enough room to get your mallet strike started.
  • Fussing around with the wedges during glue-up (especially when you don’t have anyone to help you) takes precious time. The liquid hide glue that I use gives me a little more time, but still.

One of the speculative ideas that I had last time was I could add a hook to the upper wedge, so that I’d only need to hit one end of it. I did this, with one other change:

I planed a groove into the top and a matching tongue into the bottom with some old wooden match planes I picked up in Alameda many years ago. (Note to self: regrind those plane blades, they’re in awful shape.) This eliminates the slipping askew and generally makes it much easier to get the wedges set up.

With that in place, it was much easier, but I still had some difficulty finding the room to set the wedges at times, and didn’t really have a feel for how much I was tightening the joints. So I came up with this dumb hack to do the final tightening:

Even though using a little F-clamp like this might look like it could back the hook off of the peg, it hasn’t happened to me in practice; it just shoves the lower one into place. In any case, this made the job a lot easier.

In addition, I made new pegs out of ash to discourage dents from forming in them. I suppose that I could do that with the upper wedges as well, but that hasn’t caused any problems (after all, the upper wedges aren’t supposed to slide).

So now what do I think of using them?

Overall, I’m pretty happy. One of the things that I like the most is that you perform glue-up against a wall with the work sitting on its side. This makes it a lot easier to get things in place, and it’s also relatively easy to do a dry run of the glue-up and clamping, or at least get a good idea of what’s going to happen. Once you have everything in place, you can easily check both sides by just tilting it one way or the other. And because it’s already against a wall and not on a bench or anything, you don’t have to move it afterward to reclaim your space.