Water etching

[Daniel Spruyt]

Hi Nadine,

An ordinary brush for oil or watercolor painting will do.
There may be a misunderstanding about shellac consistency. If too thick it will not penetrate into the clay, if too thin, it will crumble away while washing. Unfortunately I have only a vague idea what % I use as the bottle goes now for ages. I aim for 20 % shellac flakes in ethanol (denaturated).

[Daniel Spruyt]

Hi Larry,

It is quite simple (see also the article attache earlier in this discussion):

Let the raw object dry till bone dry. Draw a design with pencil and paint it with shellac. After complete drying sponge the surrounding clay off with a wet sponge or as used in this discussion spray with quite some pressure water close to the object (2-3 cm) the clay is removed and leaves a bas relief of .5 to 1 mm. All kinds of variations are possible: using colored slips that will be washed away except on the masked design and so on...

By the way: you encouraged me - on personal  mails- to publish my 'innovations' here - I am too busy by being lazy these days -:)  but I consider it.

Lawrence Weathers said:

Could you describe the series of steps used to get this effect

[Daniel Spruyt]

I have made album on the photo page with examples of my water etched pots (not all of equal beauty...)

[Daniel Spruyt]

 Water Etching - How I do it.

 

 On request I give here an explanation how I proceed to perform water etching.

  (English not being my mother language, it may be a bit crippled. Don't hesitate to let me know if something is not clear)

Basic equipment and materials

 

• ·       Shellac solution: preferably made from shellac flakes dissolved in ethanol. (Unfortunately I lost my notes on the quantity) I would start by putting 20 g shellac in 100 ml alcohol. Let it stand overnight, even better a few days. The viscosity should be that of a good classic varnish. If not, add ethanol to dilute it or add shellac and leave it again overnight.

• ·      Common normal brush for oil or watercolor painting

• ·      Compressed air supply able to generate 8 bar (100-110 psi).

• ·      Spray gun

 

 

Procedure for etching

 

• ·       Let your object dry completely to bone-dry. Despite of what may be mentioned elsewhere, the dry object will not crack when spraying water on it (at least I never experienced it).

• ·       Draw your design in pencil on the pot. Keep in mind that fine lines are prone to be damaged while etching, although it is possible to repair it or to have good results without damage as well, if you are lucky.

• ·       Fill the design by painting it with shellac. Use medium size brush for large areas and a fine brush for small areas or to complete the edges of the design.

• ·       Proceed by small areas at the time, e.g. 2-3 cm².

• ·       Saturate the area with enough shellac. Thin, semi-matt areas will easily be damaged. The filled areas should be somewhat shiny, dark brown.

• ·        Work meticulously - unwanted jagged areas are ugly.  If you go outside the design, the excess shellac can be  removed carefully with a sharp knife.

• ·       Let dry completely - this is achieved after a few minutes, but for all precaution, wait about 15 minutes.

• ·       Put your work piece on a wire tray so that the water runs freely off the object, without soaking the bottom.  Put the tray and object above a receiving pan - or dispose of the water at your best convenience. You will use a fair amount of water!

• ·       Use a spray gun able to deliver water at relative high pressure, high throughput. Compressor regulator set at e.g. 8 bar (110 psi).

• ·       Spray the water on the design holding the spray gun rather close to the object: 2-5 cm (1-2 inch).

• ·       Proceed here also with small areas.

• ·       Watch closely on what is happening: you will see the water jet 'eating' the surrounding clay of the design.

• ·        If you see shellac being removed: stop etching immediately ! Dry the excess water from the object with a sponge or a cloth, dry further with an heat gun. Repair with shellac.

• If you have to spray large areas, interrupt the etching after 2-3 minutes etching, dry the object roughly with an heat gun, then continue etching.

• ·        When finished, let the object dry completely like if it was a freshly made, wet clay work piece.

• ·        Bisque the object, shellac and pencil marks will disappear without a trace.

 

Remarks

 

• ·        Grogged clay is not recommend as the grog particles will protrude after etching. On the other hand, in some cases this will add a special effect. Try and judge.

• ·        An interesting idea is to cover the object to etch partially or completely with a slip of a contrasting color. Try it but make sure the slip will have the color you want after firing, some coloring additions don't stand the firing, especially at C6 and higher.

• ·      'Layered etching' A term I used in the discussion but not easy to explain. It consists in covering some parts of your object, etch, dry, cover other areas with shellac, etch, dry ... and so on. Some examples are in my photo album about the subject.

 Have fun.

[Lawrence Weathers]

very systematic and clear. Thanks

I'm on my way out to my studio to give it a shot.

[Lawrence Weathers]

water etching is a very cool technique. However, it would appear that you can get many of the same effects simply by carving at the leather hard stage. Under what circumstances is water etching preferred over carving and visa versa?

[Nadine Mercader]

The etching allows one to create a relief effect which has the same amount of relief across the entire surface. The depth of cut is far more variable when carving in clay, which I also love to do. Also the level of detail is far easier to achieve with a brush in a shorter amount of time. It also allows one to use stencils if that is desired. I own a paper/vinyl cutter which I can use to cut stencils from my own drawings created in Corel Draw and other software. That means I can create as many stencils as I desire and that makes the design element repeatable as often as I choose. I haven't used the Silhouette portrait for that yet but that is in the plan!

[Daniel Spruyt]

I think carving is much more tedious and time consuming - at least for detailed designs. It is difficult to compare both techniques, both have advantages and limitations. For instance, etching creates relatively shallow reliefs unless going for the more difficult 'layered' method. Try and compare...

Lawrence Weathers said:

water etching is a very cool technique. However, it would appear that you can get many of the same effects simply by carving at the leather hard stage. Under what circumstances is water etching preferred over carving and visa versa?

[Carolyne Tighe]

Did you find that the shellac worked better than a simple wax resist solution? I made two pieces of pottery using the wax solution as described in the article (link posted about six posts above in this thread), and I had great results. I did use a hair dryer after each water-spraying session, but I don't think It was all that necessary. I also carved through the was resist to add details. Could I carve through the shellac as easily, I wonder?

[Daniel Spruyt]

Hi Carolyne,

Personally, I don't like wax or wax solutions much. I tried them as resists but not for water etching. My feeling is that shellac allows finer, detailed painting. The use of a hair dryer or heat torch depends on how hard one has to spray water to achieve the desired results. It also depends on the 'compactness' of the clay used. You can easily cut through shellac and I guess with less jagged edges than with wax. Do you have pictures of your work ?

[Daniel Spruyt]

There are magnificent examples of water etched ceramics on the Internet.

Arne Ase is one of the masters (much on porcelain):

Arne Ase

Angela Mellorand may others...

Also Pinterest has many beautiful examples of (general-)ceramic work.

[Daniel Spruyt]

Another alternative to water etching is sand blasting. I have little experience yet, but I have seen examples that are worth seeing. It is faster than water etching and no hassle with drying (and the mess you make...). Stencils to mask the dry clay can be of any kind: wax resist, shellac(?), latex based glue (wood glue), rubber cement, cut paper or plastic, Tyvec...

If I gain experience I will let you know.

[Carolyne Tighe]

I decided to try a more detailed wax resist design today. It was a nice day outside and I thought I'd try using the hose, as suggested in the article mentioned above. Well, I blew half the design right off the pot,lol.