Monday 9 July 2018
Nearly two centuries ago makers of Biedermeier furniture in Central Europe selected pale woods from native stock such as oak, ash and birch to contrast with decorative features made from rich tropical woods, most notably ebony. The Biedermeier approach was a cut-down derivative of the ornate French Empire style, rationalised to replace brash ornamentation with folk art and functional simplicity.
Along with Shaker, Arts and Crafts and Bauhaus, Biedermeier is to some extent minimal, but it retains strong evidence of its roots. To modern eyes the process of selective simplification conducted by the original Beidermeier makers created unpretentious furniture that in many cases was far more elegant than its French Empire predecessors.
There is very little original Biedermeier around. However, when recreated as a contemporary style it has wide appeal.
In this article we will look in detail at some techniques for making furniture in the Biedermeier style, creating ebony columns, ebonising oak, making contrasting beading, applying sabots, sawing marquetry and cutting window marquetry.
Ebony is brittle and immensely dense, but not difficult to work once you get to know its character. Solid ebony turned on a lathe to make columns may have been a viable option for the original makers of Biedermeier furniture but nowadays it certainly could not be considered an ecologically efficient use of the beautiful black wood from the small tropical ebony tree.
Ebony veneer, however, is available both as the traditional rich black African ebony and as Macassar ebony with a variegated brown vein figuring running through the black.
With the grain running longwise, veneer can be wrapped around a cylindrical hardwood pole to create an ebony column. Before attempting to wrap it or apply glue, the veneer must be dampened to prevent outward curl and reduce the risk of splitting.
The straight edge on the veneer is taped onto a cylindrical hardwood column using veneering tape, the gum of which is activated by moisture. Glue is applied to the veneer while it is being rolled around the column. The veneer may be wide enough to wrap around in one turn or it can be more manageable to veneer one side of the column at a time.
The final edge-to-edge joint is cut on the overlap with the knife very slightly tilted. This shortens the edges so they meet without slack when the overlap is removed.
A vacuum bag is the ideal press for veneering irregularly shaped surfaces such as a round column. Air pressure acting through the bag pushes equally in all directions with a force of one kilogramme per square centimetre. This ensures that, so long as the glue is evenly spread, there is no possibility of leaving blisters.
The process described as ebonising simply means turning a pale wood into a black one. Clearly there are many methods by which this could be done, most obviously by staining.
To avoid a coated appearance, the stain is generally a spirit type that soaks into the wood without leaving a surface layer or raising the grain.
Alternatively, wood can be ebonised by creating a reaction between the natural tannins stored in the heartwood and a solution containing iron. This reaction is well known to anyone who has inadvertently used iron or steel fittings on oak and seen an inky-black stain develop where the wood moisture dissolves iron deposits.
Household vinegar containing a handful of rusty old screws, stood for a couple of days, makes an effective ebonising solution for oak. The reaction at the surface of the oak will take a couple of hours, but left for a day or two the blackness will penetrate deep into the oak. This is important because vinegar, being water based, raises the grain so it needs a light sanding once the wood has been rinsed and thoroughly dried.
When using ebonised oak and pale oak together take care that the iron-rich solution cannot leach into the pale oak and discolour it.
Ebony beading can be used on pale woods to provide an underlining contrast, such as on the apron of a table in the Biedermeier style. In the example here I used ebony beading on the curved rail of a semi-elliptical table.
Ebony is a brittle wood and does not take kindly to being bent along the grain so it needs to be cut in very thin in section. Ebony is available in millimetre-thick strips designed for stringing or it can be built up from numerous layers of veneer. If you buy stained ebony-coloured stringing, beware that the colour may be only skin deep and that the pale internal colour will show through when it is shaped.
To form the beading, thin strips of ebony are laminated along the edge of a pale wooden rail. Once the glue has set the bonded laminated edge is profiled with a U-shaped scratch stock blade. Suitable steel for this can be salvaged from old hacksaw or bandsaw blades, shaped with files and grinding wheels. I use an old marking gauge as the stock, but specially shaped scratch stocks are commercially available.
Standing on sabots
Black ebony wooden shoes or sabots beneath the pale legs of a tall cabinet or table in the Biedermeier style can be used to draw attention to their length as a strategy to enhance elegance. The sabots can either be made in the form of solid wooden blocks attached to the ends of legs or, as shown here, thick bandsawn plates glued into rebates at the lower end of each leg.
Before slicing the ebony into thin plates on the bandsaw, the surface is hand planed and this stage is repeated after each bandsaw cut.
Laminated in place, the ebony plates are chamfered and planed in line with the legs to form a smooth transition between legs and matching sabots.
In the original Beidermeier era small makers would have cut marquetry with a fretsaw working on a birds-mouth saw table. Larger concerns might have owned a marquetry horse or donkey. This was a sliding wooden frame mechanism operated by foot power to keep the blade running true while it freed both hands for guiding the veneers.
It is still quite practical on a small scale to cut through several layers of veneer using a fine-toothed blade clamped in a fretsaw or a jewellers saw. The work must be well supported by the birds-mouth jig with a narrow V-notch cut in the working end.
The veneers are laid in sequence in a pad, supported above and below between layers of card or hardboard with the pattern marked on for guidance. The layers can be taped together or stuck at the edges with paper gum. There is no great physical effort required to saw by hand but it does take practice to keep the blade moving vertically in one position while feeding the veneers into it.
The electric scrollsaw, a modern replacement for the marquetry horse, also frees up both hands. A fine-toothed blade is suspended vertically from a sprung arm while the lower end is pulled down in rapid strokes by a variable-speed motor.
One problem with sawing marquetry is that the saw kerf width leaves a gap in the finished work. These can be eliminated by setting a small tilt on the scrollsaw table. The table is adjusted to bevel each edge inwards by a few degrees, compensating for the material removed by the saw kerf. On rounded edges this creates a conical cut.
Using thick bandsawn veneers or a packer between thin veneers avoids the need for a steep angle. After a few practice runs on scrap to calibrate the angle, it is possible by this method to achieve a good gapless fit.
A disadvantage of tilting the table is that it prevents the offcut parts from fitting each other to make extra patterns.
Using the window marquetry technique, individual shapes are cut out with a knife blade. A progressively smaller series of shapes is marked and then cut, at each stage using the previous work as a window or template for the next one.
A large piece of veneer is chosen as the background. In the past the pattern was traced onto the background veneer using carbon paper.
Carbon paper is not easy to find nowadays, but you can simply rub soft pencil on the back of a pattern, then turn it over and trace the pattern to imprint onto the veneer. Alternatively, use a transferable inkjet paper or draw the pattern onto the veneer by hand.
The largest pattern areas are first knife cut from the background, creating windows which are then used as templates for cutting shaped pieces of contrasting veneers. The shaped pieces are edge glued into position inside the windows.
Smaller details of the pattern are then marked on the pieces, windows cut in these, then smaller pieces of veneer inserted inside them, and so on.
The knife used for window marquetry must have an extremely sharp pointed blade so it can negotiate tight curves. It must be narrow too, such as a Swann Morton Number 10A or 11 in a surgical knife handle.
Blades like this are quite fragile and intended to be disposable, but with care they can be honed many times.
In order to make reasonable progress, the window marquetry method requires the use of quick-setting glue. Traditional animal or hide glue is ideal for this, and it also has good gap-filling properties, just in case these should be necessary.
Alternatively use masking tape to support veneers while slow glue sets.
The advantage of window marquetry is that there is no kerf width to allow for so components can be as small as you like and in theory the fit can be near perfect. You can see the pattern build up progressively and monitor the quality of each piece as you cut and fit it. The disadvantage is that this method is time consuming for work of any complexity.