What the Elizabethans can Teach us
Wednesday 15 September 2010
John Bullar looks at Elizabethan techniques that relied heavily on use of the adze and on glueless joints
Furniture in the Elizabethan era of the late 1500s was made by carpenters or joiners who also used their skills with wood to make all manner of other constructions and implements.
Cabinetmaking had not become a separate craft in its own right at this time, but skills particular to furniture making were starting to emerge. This article explores what we can now learn from some of these early techniques.
Although the use of hide glue made from animal skin and bone goes back much earlier, and given the right conditions it can be immensely strong, often glue was not relied on to hold Elizabethan furniture together.
This may have been because British homes did not have the right conditions for glue. The floors would have been damp, transmitting moisture into vertical posts and softening any glue in joints. Damp glue will very quickly grow mould and start to rot. Also, the larvae of furniture beetles are attracted to eating into pockets of softened animal glue, and then for afters munching the surrounding wood.
Under the adze
At first glance the shipwrights adze with its long crooked shaft and weighted blade looks rather like the more familiar foresters axe. Unlike the axe though, which has its blade in line with the shaft, the adze has its cutting edge ground across at right angles to the handle. In this regard the adze has more in common with the mattock, a rough tool used for grubbing out tree roots.
However, despite its size and weight the adze is a fine tool capable of shaping work. It has a gently curved cutting edge. The horizontal front of the adze is ground flat, level with the underside of the blade, while the top is bevelled at around 30 degrees with the tip finely honed.
Applied with care, the adze can create a distinctive wave-like texture to surfaces which can be near to flat for panels, or controlled to shape the wood as need be. Cutting with the grain may be possible, but generally cuts are made across the grain to minimise tearout.
The feet are kept well apart. Carefully controlled chips are used to guide the adze rather than large swings, so that if the blade is deflected the impact is minimised.
While this may seem obvious I feel I had better include a word of warning here. If the adze slipped off course it could cause severe damage to your feet. Steel toecap boots are essential but there is still a residual risk of cutting beneath the unprotected sole or from the side.
Probably the most widely used glueless joint in modern cabinetmaking is the solid wooden panel housed in a grooved frame. This system was used by the Elizabethan makers for the same reason, because it would allow large-area panels of solid wood to move with the seasons, without straining or breaking the frame.
Modern flat panels often have fielded edges, chamfered to wedge neatly into the groove inside the frame. Elizabethan panel edges would often not require fielding because the adze could be used to taper the edge.
Adzed panel work has a distinctive appearance and feel to it that is strongly characteristic of the Elizabethan age. More sophisticated panelling involves linen-fold carving which was very much sought after by the Elizabethans.
Grooves and ridges are scored along the grain direction followed by deeply undercutting the end grain at the top and bottom panel edges to simulate folds of hanging cloth. It is easy to see how this pattern developed from the natural grooving of cleft oak.
Nowadays linen-fold panels can be cut with a router followed by hand carving to shape the ends. They could even be made by CNC, but much of the charm of the design is in its hand-worked variable nature.
Rough or smooth
One practical problem for the modern maker is that a torn surface created with an adze working across the grain cannot be sanded by conventional methods. If you need to smooth it you must either sand by hand or use a curved sole on a sander. Fabric-backed abrasives are pretty much essential as paper will tear when pressed into a dished shape.
Elizabethan makers sometimes used shagreen, the rough skin of a shark, as an abrasive to smooth surfaces, or else they left it uneven, allowing time and usage to smooth it.
Treenailing was a traditional way of holding wooden boats together. Holes were bored through beams and planks, then shaped oak pegs were driven in to lock them tightly together. You still sometimes see the technique used to hold chestnut picket fences together.
Treenails do not rust or stain the wood and they do not work loose in dry weather so they are practical for outdoor furniture as well as good looking in a rustic context.
One of the tricks passed to us from Elizabethan joiners was to pre-tension mortice and tenon joints with pegs driven in through the sides. The pegs must be fairly close to the joint shoulder so that seasonal movement in the mortice wood does not strain them.
Holes are first drilled in the sides of the mortice. The tenon is then inserted but not drilled. The centres of the holes are marked and then the tenon withdrawn again.
The holes in the tenon are then centred a millimetre or so closer to the shoulder. This means that when the pegs are inserted they are extra tight, driving the joint together.
Simple repetitive low-relief carving using the natural shapes created by a gouge provides a frieze pattern typically used on Elizabethan furniture frames.
Gouges were ground out of round iron bar-stock and chisels were made from iron strips beaten flat. These provided the basic shapes used to form the lines and curves in carving.
Elizabethan furniture was often made as a wedding gift or to commemorate some event, so simple letter carving was a feature commonly used. The letter shapes were flowing and quite variable. Today we generally base designs of letter carving on Roman classical styles which were popularised in Britain after Elizabethan times.
Fumes and wax
Pale oak is generally seen as a modern trend. The wood naturally darkens on exposure to air and light. Even UV-resistant water-based acrylics can only slow down the process.
Rather than resist the inevitable, oak was darkened in the past by standing it in stables. Here the ammonia fumes from horse urine reacted with the tannin in the heartwood of oak to turn the pale straw colour into a rich grey-brown.
The paleness of freshly cut oak can be mellowed by fuming it in the vapour from household cleaning ammonia poured into a dish beneath a plastic tent.
The process takes from a few hours to a few days depending on the nature of the wood and how dark you want it.
Another word of warning here. Ammonia fumes can be severely damaging to the lungs as well as being very unpleasant to breathe. The work is safest done outside on a still day.
Beeswax finishes were used by the Elizabethans. The easiest way to apply solid beeswax is to warm the wood with a hot-air gun, rub it onto surfaces and brush it into carvings and corners.
In fact beeswax applied during construction lubricates the work of hand-tools and generally makes the assembly process run smoother, ideal if you are not planning to use glue.
Rather than making the inlay as thin as possible and relying on glue to hold it and stabilise its shape, the Elizabethan maker used inlays in the form of shaped wooden tiles. They would saw the pieces of inlay to a thickness of several millimetres, great enough to keep their shape when pressed into corresponding grooves or sockets cut into the furniture.
Contrasting woods have always been popular in combination to decorate and emphasise the shape of furniture.
Inlays were made from native woods readily available such as bog oak and holly. Holly wood is bone white with very little visible grain. Bog oak conversely, is charcoal grey or black with a clearly visible grain structure.
Bog oak from the trunks of trees preserved beneath bog for millennia would have been much more common to the Elizabethans. Old wetlands were being drained for the first time and converted to pasture, and at that time agriculture had not yet cut deep into the soil.
Elizabethan furniture makers employed by the gentry enjoyed access to plenty of wood and were not afraid to show it off, hence the fashion for immensely thick tabletops and large bulbous gadrooned turnings on vertical posts supporting them. However, on a more moderate scale there are many features from the Elizabethan era that we can assimilate in contemporary designs.