Rust printing with shellac
I find myself in another rust printing phase – it seems to happen like that, the rust takes over and I can think of nothing else! This time my experiments led me to using shellac as a mask, and also combining this with China-graph wax crayons.
As previous posts on rust printing generated quite a few questions and comments I am going a bit deeper into the process of rusting here. If you investigate the topic on-line you will discover that rust is seen as the enemy and most of the information is about how to prevent it. However, this information is useful for us as we discover how to use and manage rust for creative purposes.
‘What is rust’
“The iron and the oxygen and water in the environment together undergo a chemical reaction. It forms iron oxide – better known as rust – which accumulates over time.
Chemists call this process oxidation. Water helps iron atoms more easily shed their electrons, which are negatively charged particles. Oxygen acts like a tiny electron thief, stealing those electrons and leaving the metal weak and crumbly.
The shiny, metallic iron used in homes and industry is a refined form of what is found in nature — iron ore. Rust is a natural process — the refined iron is essentially trying to return to its original oxidised, stable state: iron ore. “
This good clear explanation is from “The conversation”, a kid’s science site;
Apart from the interesting fact that iron rusts as it returns to its source, reversing the human intervention, the key information for us is that in order for metal to rust it must be in contact with both water and air.
There is more than one sort of rust
This extract is from Curtiss Wright Surface Technologies website, and gives a good description of the different types of rust.
Oxidation is the general chemical reaction of losing one or more electrons in an atom, molecule or ion, however, rust is an oxidation reaction only when iron reacts with water and oxygen. There are different colours of rusts and it’s important to know the difference so you can treat them correctly.
Types of rust:
Red Rust: Hydrated oxide Fe2O3•H2O (high oxygen/water exposure)
The most common type of corrosion is uniform corrosion. This is where an even layer of oxidation appears across the surface of the material. When metal is exposed to high volumes of water and oxygen, the iron oxidises with a contaminate, this creates “red” rust.
Yellow Rust: Iron oxide-hydroxide FeO(OH)H2O (high moisture)
Yellow rust is present in metals that are found in large amounts of standing water. This type of rust is usually found in a solvated state, commonly found near sinks and bathtubs.
Brown Rust: Oxide Fe2O3 (high oxygen/low moisture)
Brown rust can react even with lack of moisture, compared to the others highlighted above. Unlike red rust, brown rust can form as non-uniform corrosion, appearing on specific areas of the material rather than the overall surface. The manufacturing process can usually be the result of brown rust when contaminates are found on metal surfaces
Black Rust: Iron (II)oxide – Fe3O4 (limited oxygen)
Black rust can form when oxygen cannot reach the material, perhaps it is trapped and covered by another material resulting in a stain-like reaction. Unlike the other types of rust, black rust does not produce as quickly and is not as common which makes it easier to combat.
You will probably discover most of these types of rust as you investigate rust printing. Some colours come quickly, in a matter of minutes in the right conditions, others take hours, or even days to develop.
By the time you reach black rust your paper may be breaking down as well as the metal, because at this stage the rust seems to grip the paper and it tears apart when you remove it.
Cleaning Rust plates
If you have used a metal plate many times the rust can build up, and if there is a lot of black rust this can delay or even prevent further rusting. I used a wire brush and electric sander to clean the rust off the plates before degreasing them prior to masking and printing.
Controlling the rust
It is fun to print rust from old metal objects, or flat metal sheets to see what develops, which is always interesting. However, I wanted to produce some specific designs on the rust print.
For this you need to stop the metal rusting in some areas, while still keeping the damp paper pressed closely to the steel. I found shellac was very effective for this, and combined with a waxy crayon I had very good results.
Shellac is spirit based so not affected by water (unlike acrylic gels – not so successful for rust printing) It is also very runny and thin so it doesn’t raise any areas of the plate surface. Any raised areas, even tiny, can prevent the paper touching the surface so rusting will not happen.
How to do a rust print with shellac
Draw on the steel plate with waxy crayons, if wanted. These make nice marks and soft lines. Brush on the shellac, this will block the rust and you can create quite detailed designs. I used two layers of shellac – the rust did eventually break through in places.
It is worth trying out different papers as some take the rust print better than others. I used 300gsm watercolour paper and 220 cartridge. I also included layers of thin papers suitable for Chine Collee; hosho and wet strength tissue
Soak paper in vinegar/water/salt solution. The vinegar and salt both speed up the rusting reaction, the exact quantities dont seem to matter too much, I used about 40% vinegar to 60% water and a good shake of cooking salt. You can also sprinkle salt directly onto the metal plate. Lay the wet paper onto the metal plate, cover it with some newspaper and a wet blanket.
Get more prints!
Add layers of thin chine collée papers next to the rusty plate. These will pick up the rust print and allow the rust to soak through to thicker paper on top as well.
Check carefully for white gaps, caused by the surfaces drying out or paper bubbling up – re-wet these and press down again if you dont want them on your print.
Leave your piles overnight, or longer if you can. Just as long as they don’t dry out as this can cause the paper to stick to the plate.
A studio full of prints
As you can see rust printing has taken over the studio. Working with natural processes is endlessly absorbing.
As well as iron, water and air the other element is time. I prepare a series of plates then stack them with layers of paper and blankets to leave overnight. By 6am the following morning I can’t help myself – I am out there peeping into the bundles and can never resist opening them up.
The joy of discovering new prints that grew overnight is so wonderful!
We have a new feature on the website – you can add photos to your comments! So if you have a go at rust printing please do share the results in the comments section below, I’d love to see them. (n.b. There will be a delay in them appearing as they are moderated)
13 thoughts on “Rust printing with shellac”
Hi Emily, thank you for your post on rust printing, I share your fascination.
I have been doing a bit of this over the last couple of years.
Do you have any suggestions for sealing the rust print?
I haven’t sealed the prints, and I am not sure why you would need to as once dry they are quite permanent and don’t flake off or smudge. It would be good to know if you have sealed yours, and if so what did you use?
I had thought of sealing them with cold wax, and giving them a polish but not tried this yet…..
Thanks Emily,
I used some Matt Spray, but it dulled the rust colour that had printed.
I do soak the prints in water after printing to get rid of the vinegar.
Then dry them slowly, so maybe I won’t seal in future.
Fascinating. I’ve experimented with rust and fabrics – wrapping paper and fabric around rusty objects on our local pier. You never know what will happen. I always enjoy your blog.
the rust prints are beautiful, really!
l didn’t quite understand what the wax crayon’s purpose is. Do you heat the plate and melt it?
Thanks for your comment Tamara. The wax crayon waterproofs the metal and prevents it rusting, so the areas with crayon on will print lighter on the paper. I didn’t heat it, just made a firm line with the crayon.
so the crayon and the shellac both block the rusting?
I absolutely love rust and often pick up found objects made of iron. I love the fact that time is needed and I too get excited about what surprises are in store. I mostly ecoprint with rusty cans and fabric and paint with heavy rust water. I think I’ll keep a few cans and cut them open and lay flat. Just a quick question. Do you layer the papers over the one plate?
its great to hear from a fellow rust enthusiast!
yes I do often layer papers over one rusty object – sometimes you get lots of layered prints, becoming gradually paler the more layers of paper you add. I found this particularly good with wet strength tissue which I then used for chine collee in other prints.The rust patterns just kept on going through all the layers of thin paper.
sometimes I build up big sandwiches of rusty steel plates with papers between them – depending which way up they are stacked the ones below can absorb more rust as the salt water trickles down…..
Hello, and thank you for sharing these experiments! Gives me some ideas. I’m just starting to play around with rust. I know iron oxide can degrade paper over time, so I’ve been searching online for info on neutralizing those effects to increase longevity, but haven’t found anything other than AI summaries I don’t trust at all. If you’ve found anyone sharing info on that I’d love to know!
yes, it does seem hard to find concrete advice on line, perhaps the chemistry department in your local school or university could be of more help? Any information you discover is welcome here!
Another great post. What efect do you think the vinegar has on the longevity of the paper?
As acid is not good for paper I generally try to soak and rinse it as well as possible to remove the vinegar…