by Alan Li
Did you know it’s easy to make your own drawing ink from black walnuts? Every year I make a batch of ink for the students in my Introduction to Nature Drawing workshop at Toronto Botanical Garden. I’ll have up to twelve people in the workshop, so I end up collecting sixteen black walnuts to make enough ink for everyone. Sixteen nuts will make about eight fluid ounces of ink.
If you’re making ink for yourself to do the occasional drawing, five black walnuts will be plenty.
Below, I’ve outlined the steps involved and listed all the items you’ll need.
● black walnuts (soft and blackened)
● old pot and rubber gloves
● glass jar with airtight lid
● large glass measuring cup
● stirring spoon
● wire sieve for coarse straining
● coffee filter or thin cotton cloth for fine straining
Collect your walnuts and wait for them to blacken. Store them in an open container till they’re ready. Don’t seal them in a bag or an airtight container or they’ll become moldy due to a build-up of trapped moisture.
Once they’ve blackened, break into the skin with a butter knife and chop it apart into an old pot. I suggest you wear gloves. You only need the hull which is the black pulpy material surrounding the walnut. You can put the nuts out for the squirrels or roast them in the oven for eating.
Fill with enough water to just cover the hulls.
You may find little maggots inside some of your walnuts. Don’t be alarmed. There’s an insect called the walnut husk fly that deposits its eggs inside the skin of the walnut while it’s still on the tree. As the maggots grow, they feed on the pulp, and this can cause the nut to falling prematurely to the ground. If you have walnuts packed with maggots, break the hull apart and lay it out on a lawn so the maggots can wriggle away. Collect the maggot-free hulls afterwards and continue.
Bring the hulls in water to a rolling boil, then turn down the heat and continue gently boiling. Some ink makers suggest boiling for two or even three hours. I found that an hour was enough time for my latest batch of ink. It’s not an exact science. You’re basically reducing down the liquid until it’s concentrated enough for your intended purpose. I’ll repeatedly dip a popsicle stick into the liquid as it’s cooking and draw lines onto a piece of paper with the wet stick. Once I’m happy with how dark it appears, I’ll turn off the fire.
Once the liquid has cooled down, position a mesh sieve over a large measuring cup and scoop chunks of hull and liquid into it. Do this in the sink - it’s messy! Using a spoon, press the mushy hulls around to extract every drop of inky goodness.
The ink still contains sediment and will need another straining. Take the liquid in the measuring cup and pour it through a coffee filter of fine cotton cloth into a glass jar. A small Mason jar is ideal. At this point, you can start drawing with your ink, but there are some final things you need to know first.
Black walnut ink attracts mold and some ink makers add a few drops of wintergreen oil as a preservative. Vinegar is also suggested, and I’ve even heard of people who add Lysol to their ink. I don’t do any of that. I just keep the lid on tight and store the ink in my fridge. I’ve kept ink for well over a year that way and have never noticed any mold.
The walnut ink will be watery, and if you want it to match the viscosity of store bought ink, you’ll need to add a thickening agent. Gum arabic, which comes from the sap of the acacia tree is your best option. It’s available from any good art supply shop. Some folks thicken their inks using honey. You’ll need to experiment to see how much to add, but I would suggest adding a few drops at a time and doing tests to see if it’s the right consistency for you. I actually like it without any thickeners and use it as is.
Another additive which can change the look of the ink is rust. Some artists will drop pieces of rusty metal into the ink to warm up the colour. Again, this is optional and something you may wish to try.
The last thing you should know is that the type of paper you use matters. It matters a lot, actually. I prefer paper that is sized, which keeps the ink on the surface and prevents it from getting sucked into the fibers. Good examples are cotton watercolor papers made by Arches or Fabriano. The best approach is to test various papers and compare the results.
That’s all I’ve got to say about making ink! Give it a try and discover how fun it is to make your own art materials.