First steps in wet moulding leather
When we teach beginners classes one of the exercises we undertake is to make one of these leaf bowls.
The reasons for this are many but essentially it is to introduce a number of skills working on an organic shape rather than something perfectly symmetrical where any errors would be much more obvious. The leaf shape is very forgiving and you can change the shape a little if you need to.
The most important learning in this exercise is to experience the wonder that is the wet forming of leather into a desired shape which, after drying, will hold that shape.
This can only be undertaken with vegetable tanned leather of reasonably thickness and a firm handle/temper. For this tutorial I will be using Natural (un-dyed) Veg tan shoulder of 3-3.5mm thickness and very roughly the size of an A4 sheet of paper.
Cereal packet cardboard makes excellent pattern material onto which you should draw a 4cm grid pattern and transpose the outline of the leaf onto the cardboard.
Cut out the pattern with a disposable craft knife (the type where you can break off a fresh section to get a fresh new tip to cut with), NOT your leather cutting knife, as cutting paper and cardboard blunts knives very quickly and you need a sharp blade to cut the leather.
Place the pattern on the grain side of the leather (skin up) and trace around it with a scratch awl to leave a light outline impressed into the leather.
The first thing you need to appreciate about cutting out is that straight bladed knives like to cut straight line not curves, so one of the key learning points is cutting out lots of curves freehand which is best undertaken with a clicker knife or a craft knife with a curved blade on a suitable surface.
A green cutting mat is not the best material to cut on, the soft (sacrificial) surface actually grabs the tip of the knife and can deflect it away from the cutting line you are trying to follow. You may want to try a glass chopping board from the kitchen or a marble cheese board. Some of the curves are so tight eg at the tip of the stalk, even for a clicker knife to get around so you will need to cut them to a point and take nibbles off like a pound coin to get them to appear round.
When cutting, the optimum action is to have finger, wrist and elbow in a straight line and move the arm backwards keeping the blade at 90° to the cutting surface. There should be no banking over as you turn a corner therefore it is more appropriate to keep turning the work to where the knife is rather than bending your body or wrist.
Once cut out you can refine the shape if necessary by parring away material, like peeling an apple, and/or sanding with 120 grit sandpaper.
If you have one you can take an edge beveller and run this around the edge of the grain side and the flesh side at 45° and leaning back towards you. If you don’t have an edge beveller you can use sandpaper to create the same effect after the bowl is dry and crisp.
Another optional step is to turn the leaf so the flesh side is up and remove half the material from the stem with a parring knife or safety skiver. This will make it easier to bend into shape later but is not an absolute necessity.
Another characteristic of natural veg tan leather is that over time exposure to UV light will give the leather a suntan which is what I am advocating you do by keeping the finished bowl on a window ledge and observing how it changes over time and acquires a lovely golden glow like an autumn leaf.
Soaking the leather is called casing and is undertaken in tepid water. When immersed with the flesh side up you will observe bubbles rising from the leather which is the air escaping from pockets between the fibres and being replaced with water. Natural veg tan leather is very dry and has no treatments or waxes in it when you buy it. This means it accepts wetting readily and will be sufficiently wet when the bubbles have ceased, normally less than 10 minutes or so but leaving for longer will do no harm.
Other veg tan leathers such as Buttero are stuffed with dyes oils and waxes which are all water repellent and therefore may take as long as 2 hours to be wet through. It is at this stage that you would dye the leaf if you wished as the wet leather accepts our water dye most readily.
With the leaf laid flat on a hard surface you may now create the veins of the leaf by creating what we call a ‘crease’ which is a groove made by smooth metal that is rounded and not sharp (so that it will not cut the skin) pushed backwards or forwards with some pressure to give the desired decoration. PIC A suitable tool for this would be the handle end of a metal teaspoon.
The wetted leather will now be floppy and will not hold its shape without a support of some sort to hold the shape while it dries. To this end a pie dish is the perfect shape for what you want to achieve.
WARNING;- In its wet state the leather is very susceptible to marking so finger nails should be cut very short or wear rubber gloves to stop accidental crescent marks!
With the skin side up press the centre of the leaf to the bottom of the bowl to create a base and then arrange the outer edges in an organic and pleasing shape. Once satisfied fold the stem in half along its length and squeeze together.
After 3-4 hours at normal room temperature the shape will have set somewhat sufficient for the dish to be removed to allow quicker evaporation from the bottom of the leather bowl. Final adjustments to the shape can still be undertaken at this stage before leaving overnight to become fully dry, much firmer and set in its final shape.
Once dry the edges can be refined with sandpaper if desired and then polished (burnished) using water, Gum Tragacanth, Gum Arabic or Tokonole (the best in my opinion but not easy to get hold of at a reasonable price) and rubbed with canvas, denim or a wooden burnishing tool.
An all over treatment with leather cream will protect the skin side and give a lustre while slicking down the fibres on the snotty side.
Your bowl, known as a ‘Blessings Bowl’ is now ready to accept keep sakes and adorn your home. They make lovely gifts and are generally well received - so why not make a few.
Next Time:- Getting started with wooden moulds.
