Tuesday, 16 November 2010

Tapered sliding dovetail bench

  A bench for Garden for George

Some projects just take years. I was approached 3 years ago about making a bench or benches for a garden in memory of George Harrison. The representative and I went through all my designs and finally, a couple of months ago, settled on a design that came from using tapered sliding dovetail joints in a bowl horse. I had never made such a bench, but was comfortable making the joints for green wood work tools. A great joint that can easily be knocked apart, and which gets tighter and firmer when pressure is applied.
Again it was a short lead time and great fun to make. Just before I confirmed that I would make the bench I had to make a pre-prototype-prototype, which is what I call this little stool.

I learnt a lot about this joint made from sawn and planed timber and it took me a long time to figure out how to mark out the legs. Marking out and cutting the mortice is simple, not so with the tenons on the leg, lots of compound angles that made my head hurt. If anyone knows how to figure out these angles mathematically so they can be transferred to the legs then please let me know.My solution is simple, and I suspect it is a way that many of us actually work things out. I made a mdf angle template, for each side of the joint.

 The dovetail joint has a slope of 1in 6 just like a normal dovetail.
After making the little stool, which I really like, even though it was made with the crappiest bits of wood in my shop. It has a solidity and presence that other stools I have made do not. It also has a price tag equal to its weight, not this one, but a similar one you will commission me to make you ; )

The plank for the bench was in the £300 mark - expensive - so I made a prototype from a 4 inch thick oak plank that had woodworm. I also wanted to get the angles of the legs and back right, before committing myself to the expensive plank of wood.

One problem with making the joints for the bench was that the plank of wood did not fit through my planer thicknesser, so it had to be hand planed. I also kept the dome in the top of the wood, to help shed water, but had to get rid of any wind. I did not have the proper planes, or time, to really square the timber off as I would have liked. So each joint was slightly different, I had to make lots of these templates.

The legs are hand-planed down, and had to have lots of fitting to ensure a tight and even fit. The waste was taken off on my band-saw, rather than using one of my ripsaws.
Click on image to embiggen

The bench is going outside in a public place so I also glued the legs in to help with keeping water and eventually rot out of the legs. Most of this bench is made with hand tools and no sandpaper.

It is a simple but elegant bench that takes quite a bit longer to make than its looks suggest.

oak bench, tapered sliding dovetail joints from Sean Hellman on Vimeo.
They also come flat packed, and simpler than Ikea furniture to assemble, that is if you can lift it!