This is an exciting technique creating lovely rich tones with expressive brush strokes, and dynamic splashes.
Carborundum powder is a fine abrasive, also known as silicon carbide. You can also use emery powder (aluminium oxide). It comes in different grades, generally fine, medium and coarse.
For more technical information about carborundum and where to get it, have a look at this post.
Begin with a plate
For this method you will be adding dark areas to your plate so it is good to start with a light toned plate, i.e. something smooth and shiny. This could be cardboard sealed with pva, acetate sheet or any of your usual plate materials.
In contrast to the technique using wet and dry paper, you will be working ‘light to dark’; if your plate is shiny it will print light and this will give a contrast to the dark carborundum. It is a good idea to make sure you leave some clear areas on the plate otherwise your print won’t have many tonal variations.
Add something sticky
GLUE: Paint, dribble or splash pva glue onto your plate.
GEL: make a textured design with acrylic gels or gesso.
Don’t hang around because if it starts to dry the carborundum powder will stick unevenly.
Alternatively if you want to have more control over where it sticks, you can create a textured plate and let it all dry.
Then add a thin coat of pva on the areas to be dark before sprinkling carborundum on.
Protect your self and your work area
The dust is not poisonous but can irritate your eyes, and also lungs if it is inhaled.
Fine carborundum and especially emery powder seems to fly around everywhere and will stick to any slightly wet glue or paint. It is important to keep it contained to avoid contaminating your clean pva or creating unintended dark patches on your plates.
A good way to manage this is to have a ‘carborundum station’, particularly if there are several people at work in the same room.
For this I use a clear plastic storage box on its side. Put your gluey plate in the box before shaking the powder onto it.
Make a pounce bag
Line a small bowl with a piece of muslin. Tip a few spoonfuls of carborundum powder into the centre of the muslin. Gather up the edges of the cloth in your hand to form a little bag.
This is known as a ‘pounce’ bag and the technique of shaking powder onto a surface, often through a stencil is traditionally used in a number of trades particularly tailoring.
A deep and even layer of carborundum powder
Hold the carborundum grit in the muslin pounce bag a couple of inches (5cms) above your gluey plate.
Shake it sharply up and down to sprinkle an even layer onto the wet glue.
As it soaks in dark patches will appear; pile more carborundum on and leave it a moment until all the powder looks dry.
Recycle recycle recycle
Remember using glitter to make Christmas cards at primary school? This is the same principle.
Work on a sheet of newspaper in the plastic box, when the glue has soaked up all the powder hold your plate vertically and give it a sharp tap to shake off the loose powder.
Create a funnel with the newspaper and tip the carborundum back into the muslin in the bowl.
Leave the plate to dry without touching the surface.
When the glue is dry
When the glue or gel is totally dry brush off any loose powder with a soft brush.
If you used pva it will be covered in carborundum so will not stick to the damp paper when you run it through the press. Sealing the plate with shellac is not essential, however it will help to make it more robust when inking up.
Keep on pouncing
This technique is very effective when combined with drypoint, the thin fine lines contrasting with the deep ‘fuzzy’ areas of carborundum. An acetate plate is a good base for this.
If your first efforts seem rather dark and formless don’t be put off.
With a bit of practice you will find carborundum powder is a great addition to your menu of platemaking techniques.
Most of the illustrations here were taken on a two day printing course run in my studio. Students were carborundum powder beginners!