30 September 2012

Repousse work and a mixture called tenax.

A few examples of the repousse work I made recently.
I am experimenting with new a technique called repousse. Using punches - polished, blunt steel tools, the image is hammered down and pressed in to a metal foil. 

It was used to produce a light weight metal ornaments which where sewn on dresses and church textiles.

14th century clay "dolls" from Nuremberg (Germany) with big floral metal ornaments.

14th and 15th century dress ornaments.
Silver-gilt and copper-gilt.
Kloster St Andreas, Saren, Switzerland.
Those are sewn on a dress made for a statue imaging  the Jesus as a child.


But first things first. The metal foils is fixed on the black mixture, which the Monk Teophilus calls tenax.
In his manuscript "Diversarum Artium Schedula" from 12th century he gives the recipe for preparing it:

"Grind a piece of brick or roof tile very small (fine), 
and melt some pitch in am earthenware pot and add little wax.
 These being melted together, mingle the powder of the tile, and stir it strongly 
and pour it in water. And when it has begun to grow cold,
 dip both hands into the water and macerate it for long time,
 until you can extend and draw out this composition like a skin.
 You instantly melt this composition and will fill the vial to the top. (...)"
 - from Chapter LIX
Components ready to be melted. Some brick powder, resin, pitch, and wax (not on the photo).

Part of the original  Pages in the manuscript "Diversarum  Artium Schedula"  from Vienna.

I tired this recipe, but than I decided to add also some resin to improve the elasticity and than it was perfect. Probably if I would be working in a cooler temperature the resin would not be needed, but as I was working with it in the middle of the summer, extra resin made a huge improvement.

But what makes this composition such a good base for the working with a metal foil ?
There are several reasons:
First, when heated close to the fire it become liquid and sticky, so the metal can be easily fixed on the surface (you can also heat up the metal piece and melt it into the pitch).
It holds and stabilize the metal while working and give an elastic base to press the image down.
Secondly, it is hard enough to give a good resistance and elastic in the same moment.
Finally, what is also impotent it burns away totally which makes cleaning of the work much easier and quicker.
 Only a thin coat of brick powder remains on the surface, you can brush it away or add a few drops of water and use as a cleaning/polishing compound to bring some light to your work
A wooden board with tenax and some tenax rods for future projects.
 When the mixture is ready I pur it on the wooden board. I make 4-5 layers waiting until each one cools down before putting the next one.
I prepare the metal pieces and heat them in to the fire until they glow red, to make them softer and easier to work with.
Cutting copper disc with copy of the shears from the Mastermyr find.

If the image is deep, there might be a need to heat it again to avoid braking it while stretching. To do that,  put a glowing piece of charcoal over the metal and blow gently. That will make the metal piece warm enough to be easily removed from the pitch.
Starting with a sketch and making the border decorations.
I use steal punches to hammer the image on the foil. I work on the reverse side so it is important to check from time to time how it look also on the front side.
Close-up to the reverse side.
Avers side of the ornament, and an its image left in pitch.
Big flowers are going to be sew on a surcot, a type of dress,
 as button-like ornaments, are based on a find from Salzburg (Austria).
Smaller ones are based on a design from the bronze matrix found in Norway.
Already with little holes for sewing them on.
Workbench view.

The photo of the original find from the Salzburg Treasure.
 That was a very interesting project, not only because I had to learn a totally new goldsmith technique, it was mostly because it's a link connecting goldsmith work with a textile projects with are made in the Middelaldercentret. Two different techniques but both have the same purpose - showing the status of the owner as much as satisfying the aesthetic needs.

It also made some visitors of the museum revise their point of view on a goldsmiths work in Middle Ages, and realize that what we call now "jewellery" is quite a modern concept,
 and that it differs from a medieval point of view.

There spectrum of products made by goldsmiths where much wider: dress ornaments, buttons, hook-and-eyes, buckles, metal beads where as important as rings and brooches and pendents. Also the metals that goldsmith use was not only gold and silver as it is now. Gilded copper and bronze was extremely popular, because it made a similar efect when weared but was much cheaper to produce.

I surely going to work more with repousse. It gives a great effect and I am able to produce pieces which can be so complex but still feel very delicate and pleasant to wear.
They can be used stitched on the textiles, riveted on a leather as belt ornaments,  hammered on a chests covered with velvet, used for book covers, or as an element of even more elaborate works.
All that will be gilded with gold and sew on a new priest dress for Middelaldercentret.


Bibliography:

Theophilus: An essay upon various Arts in three books by Theophilus, called also Rugerus, priest and monk forming an Encyclopaedia of Chritian Art of the eleventh century. Translated, with notes by Robert Hendrie, London 1847.

Theune, Claudia: Der mittelalterliche Schatzfund aus der Judengasse in Salzburg. In Ars Sacra. Kunstschätze des Mittelalters aus dem Salzburg Museum. Jahresschrift Salzburg Museum 53, Salzburg/Oberndorf 2010, p.

http://www.landschaftsmuseum.de/Seiten/Lexikon/Spiele-Puppen.htm
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5 comments:

  1. Very interesting your post.
    By this technique a lot of work and I love it.
    I have taught at the school and still use when I go to the reenactment medieval
    Too bad clothes very far because I would like to meet you

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  2. Would you share your actual recipe for the pitch? I am wanting to make my own, as this is hard to import to New Zealand.

    ReplyDelete
    Replies
    1. I make a mixture using Stockholm Tar (hoof dressing from horse riding suppliers) as 'pitch' can be hard to find and a fine powder such as as fine grog from potters suppliers. A typical recipe I downloaded is below. (I see they use plaster of paris as the fine filler).

      16 parts pitch
      20 parts plaster of Paris
      4 parts resin
      1 part tallow
      The pitch is heated until molten. Plaster of Paris is added a small amount at a time. Resin and tallow are then mixed in. These make the mixture a bit more plastic

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  3. Just great! thank you. What is the thickness of the foi that you usel, pls?

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