To modern eyes, old-school workbenches look like they are going to self-destruct.
The legs are tenoned into the benchtop (which moves with the seasons). And stretchers (that don’t move) are tenoned into the legs. Something has to give, right? Otherwise your benchtop will be cleaved asunder, creating a “split-top Roubo” a la naturel.
I’ve dealt with this issue in several ways.
1. I have ignored the problem. I just glued and drawbored everything up tight on the French-style bench I built in 2005. The result: The legs pivot a bit on the lower stretchers as the top expands and contracts. There are a couple small gaps on the shoulders on the end stretchers. No other problems to report.
2. I altered the mortises in the benchtop. On a couple workbenches I’ve made the mortises in the benchtop that receive the rear legs a little wider. And I didn’t glue the rear legs into the benchtop , I just pegged them in place. The result: The top moves. The base doesn’t. No real problems here either.
3. I’ve bolted the top to the base. This is the modern solution. I used tight holes at the front of the bench and reamed-out holes at the rear. This forces the wood movement to the rear of the bench. When the top moves, it shifts where you don’t see it. The only issue here is I wonder about the long-term lifespan of the hardware.
And now I’m pondering solution No. 4 for the workbench I’m working on now. Here goes: On the end stretchers I’m going to glue them into the front legs, but I’m going to leave the tenons into the rear legs loose.
I was inspired to do this by Roubo’s plates. Last night I was looking over all the A.J. Roubo volumes (yes another high time at the Schwarz household) and noticed that Roubo shows the front stretcher clearly pegged into the legs, but it doesn’t look like the end stretchers are pegged into the legs.
This got me thinking.
The other thing I’m considering is stealing a trick from the Hall Brothers, who built almost all of the Greene and Greene furniture. They made double mortises in some legs. So the tenon and the shoulder are buried in the leg. If I do this little trick, I’ll never have an open shoulder.
Yeah, it’s fussier than is probably necessary. But I’ve wanted an excuse to try these ideas out.
– Christopher Schwarz