here is the story of how i attempted to prevent my gouache from cracking and breaking apart. alice wrote to me with a recipe:
It will take a little while to dry completely; maybe a day or two to set up. This weather is perfect for this because it should set up quickly. I have to warn you, the process is tedious. But I've found it well worth the time and effort. I filled the pans in THIS photo in Feb of 2012 and have refilled maybe one or two since. Here's the process:
Use an eye-dropper or straw to add a drop of gum arabic to your empty pan. Then add a dollop of gouache and mix well. Continue to mix in gouache until the pan is full.
Keep an eye on the pans during the drying process. This is very important because when a "skin" forms over the top, you will use a popsicle stick or the end of a paint brush (I use a letter opener) to push the skin down. Pushing the skin down removes the air bubbles and condenses the pigments in the binder (gum arabic). You're basically making a gouache brick.
Push the skin down until paint oozes out of the corners. In some cases you may need to add more gouache depending on the amount of evaporation. Be sure to mix the newly squeezed paint with the other paint already in the pan. Don't worry about re-wetting the skin, just push it down to the bottom of the pan.
Keep condensing the gouache until the brick dries completely. The brick should pull away from the sides and maybe even fall out.
Use another drop of gum arabic to glue the brick to the bottom of the pan. Whenever you wet, dry and re-wet your gouache, the gum arabic (glue) keeps the pan stuck to the bottom.You may need to add more gum arabic to some of the more chalky colors. I add two drops to my black and white pans because they tend to be chalky.
she told me it was a tedious process and she was right! if you go to her flickr page you can see her pans of gouache are nice looking with no cracks so i'm sure it will work if you do it right. do note however that some of those pans in her photo are watercolor. i attribute my failure to user error. mine!
i won't attempt again because the exhaustion level is high and the convenience level is low. i probably needed to add 2 drops of gum arabic instead of 1 because my palette pans are larger than hers. i didn't want any sheen whatsoever, so i was wary of adding too much.
despite the cracks it still rewets nicely, but i've decided i prefer fresh. so what i plan to do is just keep adding fresh each time, putting out only the colors i will need. when i'm finished i will just leave the extra gouache there in the pan and rewet until it's all used then i'll add more as needed. that's my plan, but naturally it may change!
one thing for sure is i'm taking my itty bitty travel set of gouache with me to amsterdam. we'll see how that goes.
dick blick has some nice smallish bottles of matte acrylic which look like gouache when dry. they're only a couple of bucks a bottle. just like the cheap craft paint. i'm sure the formula is the same. i picked 7 bottles up last week and played around with mixing them together. they mix nicely. if you aren't sure if you'll like gouache or not i'd say get some of that paint first and see if the matte finish appeals to you.
i'm going to keep experimenting with ways to use my new holbein gouache and i'll share them here with you as i do. by the way i've read on various sites that m graham gouache doesn't crack, but after using it at joyce's last week that is simply not true. her entire m graham palette was cracked and in pieces. it did rewet perfectly fine though. schmincke gouache is also supposed to be crack-free and rewet nicely, but it's terribly expensive. i'll stick with my holbein for now.
this unusual mauve-toned hibiscus bloomed in my garden today. she's a big showy girl.
i don't recall the name, but it is one of the tropical hibiscus, not a garden variety.
i'll be scarce around here until i start blogging from amsterdam late next week, but i'll shoot out another post before i go with a photo of the art supplies i'm toting along. see you then!