A Paint with Character—and How to Make it (from Milk!)

If you've heard of milk paint, it's probably because you're a furniture geek: Maybe you've fallen in love with a worn Colonial-era chair, the way the colors of paint jobs past peek through the top coat along its edges and corners. That's milk paint doing its thing, the way it's been doing it since ancient Egypt.

And the smudgy wearing-away is part of why it's prized; the whole "shabby chic" trend, which spawned an industry of intentionally distressed furniture and driftwood signage, is based on the milk paint effect.

Milk paint doesn't go on perfectly even; it's mottled and opaque just in places, like a watercolor got married to an acrylic. Those who love it prize this irregularity, which looks as beautiful as lead-based paints but without any harmful chemicals, toxins, or fumes. Moreover, milk paint won't chip, instead wearing or cracking where it's thinnest (or where it gets petted most frequently). Like so many natural materials, a milk paint finish gets prettier and prettier over time.

I was recently re-introduced to milk paint when a paper bag of dry blue powder landed on my desk, a gift from the Old Fashioned Milk Paint Company. You can find powdered milk paint pretty easily these days (the Old Fashioned Milk Paint Company offers it in 16 beautiful colors), and all you need to do is mix it with water before painting it on. It even comes in cans, if that's one step too many for your taste.

But since we're here, on a site that celebrates the hand-crafting of anything that could be otherwise store-bought, it's especially important to note that milk paint is something you can make! The basic process is to curdle milk (using lemon, or lime, or white vinegar) overnight, and then add pigment to the whey. The proteins in milk called casein act the same way oil does in an oil-based paint (or egg does in tempura, and as polymers do in latex-based paint), suspending the pigments.

The following recipes is based on Martha Stewart's—hers is one of the simplest I've found, and it produces a very easy-to-use result. If yours turns out lumpy, you can add borax or bicarbonate soda to smooth it out. Just be sure to use it the day you make it (and therefore only make it in the quantities you need) because, like milk, it will spoil!

What you'll need:

• Juice of 1 lemon
• 1 quart skim milk
• Cheesecloth
• Sieve
• 4 tablespoons of dry color pigment
• Borax, optional

How to make it:

• Stir the lemon juice into the skim milk (or don't stir it, as the curds are already forming when it hits!) then leave the mix in a warm place overnight to curdle.
• Strain away the curds through a cheesecloth-lined sieve.
• Add some of the pigment to the whey (or use drops of water-based paint if you prefer), and stir until even. Continue until you get the opacity you want, adding a sprinkle of Borax if needed to help abate any lumps.
• Paint with it (see below for a how-to), and then discard whatever you don't use, as it will spoil after about a day. It can go right down the drain without any worries at all!

How to use it:

• Before painting, prepare your wood surface: It should be either raw, or sanded down if it once had a finish. The paint will seep into the surface of the wood, which is what results in that prized translucent finish.
• Paint it on using a foam brush, a thick-bristled brush, or a roller brush—it will smell a little sour, but that goes away once dry—and let the piece dry overnight. If you want a blotchy effect, let it pool where you splat it on; otherwise use steady, regular brushstrokes to get it as even as possible (though by its nature, it won't ever be perfectly even).

• If there are any little poky bumps on the surface in the morning, you can brush them away with steel wool, a dry cloth, or even your hand. There will be some paint dust that comes off, so do this somewhere you don't mind that happening.
• Add another coat if you wish to make it darker, or even a coat of a different color—that way, when it wears over time, you'll see the color of the undercoat peeking through. Some like a third coat, but that's up to you.
• Finish the piece however you like, be that an oil or a matte varnish, and let it dry another time.