Hard ground etching: The next stage

Aquatint & selective masking

Step 1: Aquatint

Aquatint is a way of preparing the print plate surface to hold a lot of ink, thereby creating a solid deeply coloured printed area.

So what is aquatint?
Aquatint is powdered resin that is applied and fused to the plate surface.
How does it work?
Imagine millions of marbles covering the bottom of an empty swimming pool, all fused (glued) in place.  If you were to walk over them you would feel the rise and fall of each marble, and if you looked closely you would see the curved dips where each abutted the next.  Now think about tipping in gallons of paint.  Where will it pool?  Well, it will sit in the crevices between the marbles and, if they are lightly applied, it will sink between them as well.

zinc-etch-13Got that?  Now scale the whole thing down – down as far as powder or dust.  By fusing the aquatint (powdered resin) to the plate and applying ink to the surface you can achieve a very solid velvety printed design.  Using dampened paper will help this as the paper becomes flexible and the pressure of the etching press pushes it into the textural surface of the inked & aquatinted plate.
How do you apply the aquatint?
The powdered resin is stored in a large enclosed chamber with a shallow drop down door.

zinc-etch-14The print plate is placed inside the opening on a cardboard support, sitting on a wire rack.

The outer handle is cranked very fast many times to agitate the resin and produce a cloud inside the box.  In my case, 3 minutes was allowed for it to settle and produce an even covering over the plate.

Obviously, this process is hazardous to lungs and we wore masks to avoid breathing in the dust.

The plate was very carefully removed (one sneeze or deep breath and it’s over!) and placed on a metal rack ready for the fusing stage.

zinc-etch-15A heat gun, one that radiates heat without blowing – so not a hairdryer – was used from the underside to melt and fuse the resin together and to the plate surface.

In this picture you can see the heating in action and the swan image just starting to appear as the resin becomes translucent.

zinc-etch-16On the left is an image of the plate once the resin has been fused.  I’ve photographed it under a yellow light so the ‘mottled’ surface can be seen more easily than on the silvery zinc colour.

Once cooled down it is ready for the next stage.

As I am working on the background and have the swan and cygnets exactly how I want them (having checked by doing a proof print before getting to the aquatint stage) I masked them so none of the next techniques used to produce the water and sky will affect them.

Step 2: Bitumen

What is an effective way to block out an area of a print plate where you don’t want the acid solution to bite?
Initially this plate was covered with hard ground wax as a resist.  The swans were then etched through the wax using an etching tool and the plate put into the acid bath to bite the areas where the tool had removed the wax.  Very straightforward.  But this technique isn’t possible when a selected area, or areas, are needed to be masked.  The wax is rolled onto the plate and cannot be carefully brushed onto particular parts because it is never liquid enough to use a brush and solidifies immediately it leaves the heated hotplate.

zinc-etch-17So a mix of bitumen and meths was made to a thick paint consistency and this was brushed over the swan and cygnets.

It’s quite a hard process because if any bitumen ends up in the wrong place, or you miss a bit, it has the potential to ruin the plate.

Keep in mind that every part of the exposed plate has the potential to be affected by the next stage of acid work.  So I took my time, used a very fine brush and blocked out my subjects.  This will protect them from further etching.  After the whole process is complete the bitumen solution will be removed with turps.

Next comes the water & spit biting to create the unevenness of sky and water.


About Claire B

I'm a passionate printmaker, paper-maker and a poor sketcher (which I'm working to improve). I've stitched from early childhood and am a perpetual student, loving learning and participating in everything creative.
This entry was posted in My Creative Pieces, My prints and tagged , . Bookmark the permalink.

2 Responses to Hard ground etching: The next stage

  1. Sue says:

    Reading this has made me appreciate the product even more!

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