Dairy go round
There are days when you just want to make your own paint from cottage cheese. That day happened for me recently when a well-meaning paint manufacturer sent me a sample of a new exterior paint.
I have an old fence that I thought I’d try it on. But when I read the preparation guidelines in the product literature I yelped with equal parts indignation and despair. Here’s a gem:
Clean the area thoroughly with a detergent solution, then rinse with a garden hose or pressure washer.
Well it’s a 400-foot fence. I’m not giving it a bubble bath. And it’s at the end of a 500-foot farm lane, so neither the power washer nor the hose will reach it. So I’m off the hook on the prep. Whew.
But wait, there’s more:
Next, scrub with a brush to remove any dirt and grime. Then use a scraper or wire brush to loosen debris from deteriorating surfaces.
Okay, so a couple of days worth of scrubbing, scraping and wire brushing. Not.
Wait! It gets worse.
Finally, fill holes and cracks with acrylic-based caulking and smooth surfaces with 120 grit sandpaper.
Come ON! I have to fill and sand 400 feet of fence? What fresh hell is this? (to quote Dorothy Parker, who clearly knew a thing or two about exterior painting.)
And that’s when it hit me. Back when no one owned power-washers and everyone had barns and wagons and houses to paint, how could they possibly have managed?
Well I found out.
They made ridiculously cheap, VOC-free, no-surface-prep-required homemade paint that could be slapped on any surface and would bond beautifully to wood, stone or brick. And it would last for ages. In fact, you can still see this paint in action on vintage structures in older cities and towns.
There’s even a clear-coat version of this stuff that I made yesterday and applied to the frame and surface of a kid’s chalkboard to create a tough, silky finish.
Milk paint (or ‘casein’) is one of humankind’s oldest chemistry experiments, first used millennia ago in Asia and Egypt. How do we know they used milk paint? We found cave paintings that had survived 9,000 years. Does your paint manufacturer guarantee your paint job for 9,000 years?
Now, modern paint does have three distinct advantages over casein. There’s no chemistry: you just open the can. It has a long shelf-life, whereas casein has to be mixed the day you’re using it and will only keep for about 24 hours. And it comes in thousands of colours that can be consistently replicated.
But if you make your own paint, you’ll spend less, you can skip prep and you’ll have the satisfaction of knowing that 9,000 years from now your job will live on, even if the object under the paint has rotted to a skiff of molecular substrate.
There are lots of recipes for milk paint; here are my current favourites:
Casein Clear Coat
- (Makes a lot — you might want to half it)
- 1 quart room temperature low-fat milk
- About 4 tablespoons of Borax
Reserve about 1/2 cup milk. Mix one tablespoon of Borax (laundry additive) into the remaining milk, stirring with your fingers until it’s absorbed. Keep adding Borax by the tablespoon until the milk stops absorbing it. Then add reserved milk till the last granules disappear.
Cottage Cheese Exterior Paint
- About 1/3 cup of hydrated lime powder
- 1/3 cup water
- 2 cups room-temperature cottage cheese
Add water slowly to the hydrated lime in a glass or plastic container and mix it gently till it’s well blended. Add water/lime mixture to cottage cheese and blend well. Leave for 3 to 4 hours; the lime will dissolve the cheese curds. Make a paste of water and pigment and then blend it into cheese mixture. Strain through cheesecloth or a clean pair of panty hose if it’s lumpy.
Note: Hydrated lime is available at Home Hardware in 6kg bags for about $13. Lime is extremely alkaline so wear gloves, eye protection and a dust mask. If you get it on your skin, rinse with white vinegar.
For more experiments and links, visit www.ToolGirl.com.