An Update on the Roubo Bench

I’m getting about a letter a day from people interested in building (or taking me to task) for the Roubo-style workbench shown in Issue 4. Reader Dan Chaffin, a furniture maker in Louisville, Ky., had three good questions about the base, then bench stop and the holdfasts that have come up a few times with other readers, so I thought I’d publish his letter here and my responses. So here we go:

First Question: When the top of the bench contracts as it dries, how much wracking of the base actually occurs (roughly)? I am not concerned about joint separation, but I like the fact that the legs are flush with front edge of the bench top, and I was wondering if the wracking would affect this flatness in any significant way.

First Answer: After five months, the bench is at full equilibrium with our shop. Our moisture meter reports that the top and legs are all about 11 percent moisture content, which is consistent with the other pieces of Southern yellow pine that have been in our shop for five years or more. So the top has finished shrinking. Now all that will occur is the seasonal expansion and contraction, which I’ve calculated will be about 1/8″ per year.

The initial shrinkage of the top did indeed wrack the base into an A-frame configuration as I reported in Issue 4. A Starrett framing square shows that it wracked about 1/16″ at the front edge of the bench (this was with the 22-1/4″-long section of the square running down the leg). I haven’t found that the wracking affects the functionality at all. The front surface of the bench is still a wide and consistent clamping surface.

Second Question: The 2″ bench stop in your bench plan sits back a bit from the front edge of the top. Is there any reason that it cannot or should not be moved closer to the front edge so that when planing narrow stock you wouldn’t have to lean over as much.

Second Answer: The bench stop could be moved toward the edge or toward the end (I’ve seen some people who do this to get the extra capacity). I initially considered it but decided to go with a configuration that looked like Roubo’s to see if I could figure out why it is where it is.

I don’t have a firm answer yet, though I’m glad my bench stop is not more towards the end of the bench for two reasons: One, I never run into my leg vise or crochet as I’m planing. And two, the space beyond it is a natural resting place for the tools that aren’t in use but must be handy while I’m working, mostly my mallet, plane-adjusting hammer and the oily rag I use to lubricate my plane’s soles. I also have a swing-arm lamp that drops into my bench dog holes that lives in that space beyond my planing stop.

I’m also glad the bench stop is not closer to the front edge for two reasons: One, narrow stock has not presented a problem yet. In fact, I even plane boards on edge up against the stop. And two: The bench stop is positioned so it will be centered on a 12″-wide board. Our jointer is a 12″ model, so it works with that tool’s maximum capacity.

Third Question: The article on holdfasts suggested that the Phil Koontz version would not seat well in tops thicker than 3″ if the holes were 3/4″. In the workbench article you show these holdfasts as well as the Veritas holdfast (which I thought only worked in 3/4″ holes) being used. Did you drill different diameter holes for the top and the sides? Or will the Veritas also work in the slightly smaller hole used for the Koontz holdfast? I would love to know before I purchase either.

Third Answer: You have a sharp eye. The holes in the top are 11/16″. The holes in the legs are Ã?¾”. Phil’s holdfasts work only in the top; the Veritas holddowns work only in the legs. I wish I had one holdfast that worked everywhere, but I don’t.

– Christopher Schwarz