Twisted dovetail coffee table

October 2004

Twisted table

Twisted dovetail coffee table
This began as a couple of planks of this fascinating brown-heart ash. The twisted timber deserved suitable joinery, so I used Japanese twisted dovetails.

Twisted dovetail coffee table - end view, showing joinery
End-view. I'd started out by planning the top as one piece, with two edge-jointed boards. The corner joinery looked better on the narrow individual boards though, so I kept them apart and joined them by small steel pins.

Twisted dovetail coffee table
The stretcher rail beneath stops you looking all the way vertically downwards and through the table.

Close up of the joinery
The ari-gata "twisted dovetail" joinery in close-up

Materials: brown-heart ash

Finish: gel poly
Epoxy filler on the splits and drying checks

I plan to write up a brief note on how to cut these joints, when I have a moment

Construction

This table took over two years to complete! I started in one workshop and did nearly all the joinery, then re-located and left it sitting on the shelves for two years. The thought of all that hand-scraping to get the epoxy filler down flush was putting me off. In the meantime the boards dried out more, and the joinery fit isn't quite as well as I'd like - oh well, there'll be more.

October 2004

First complete assembly
First complete assembly

Assembled - end view of the joinery

Twisted ash coffee table

April 2002

Lignified olive ash boards, laid out for selection

It looks more like a wooden version of the Turin Shroud, but this is two bookmatched panels of lignified ash. The centre of the tree forms this dark colour and some bizarre grain formation. Normally it's regarded as rubbish (it's very brittle) but it's quite an attractive pattern.

Lignified olive ash boards, laid out for selection

Jarkman has just made a bed from the same wood

It's weird wood, so it deserved some weird joinery. I settled on the Japanese ari-gata twisted dovetail. They're obscure, and I'd never made them before. It will probably end up looking a bit like this, but with a more interesting surface.

First I built a prototype.

Prototype twisted dovetail joint, assembled

Foolishly I made the prototype from a scrap of green ash. Within two days after cutting it had dried out and warped like crazy, opening all the carefully cut joints. Something to watch for the real one, as (with my new found obsession for moisture contents) I knew that's not quite dry too.

Prototype twisted dovetail joint, assembled

Now, on to the real table:

All four boards of the table, laid out

So far (May 2002) I've cut the joints and finished one joint so that it fits.

They're surprisingly simple to mark out and cut, but you must be exceptionally accurate if you want them to fit well. It gets harder with wider panels, so I chose to make the table and its dovetails in two narrower pieces and then join them (with biscuits) afterwards.

Twisted dovetail joint, opend up and laid out flat

Twisted dovetails usually alternate their twist alternately, so as to make pins and tails. I was working on two quite narrow boards here, so (after a great many scale drawings) I chose to repeat the slope across the middle tails. It's less traditional, but avoids a "pigeon toed" look that it had otherwise.
Twisted dovetail joint, open

Twisted dovetail joint, assembled
I hope to get it finished soon. There's a lot of open grain and checking, so I'll use a mix of epoxy and phenolic microballoons as a filler. I haven't decided on a finish as yet - needs to be hot coffee and vodka resistant, yet not hide the wood.

Ash boards, after filling with epoxy filler
They're now filled and ready to be scraped flat.