Tips for cleaning your paint brushes

Fellow woodworker Ken Richardson asked:

> What do you fellow woodworkers do with this stuff after you clean you[r] brushes? The can says “check you[r] local waste disposal regulations,” but really, what do you do? Is it resuable? Can I keep it in a can until I need it later? I'll take to our waste facility if I have to, but I thought that some one might have another way of using the stuff.

Like Bob (Lambert) said, let the solids settle out and then decant into another container. I go through quite a bit of it, so I wind up having empty bottles, which I mark and use as containers for the old spirits.

> My brushes are little stiff upon drying. How do I adjust my cleaning technique so they are as soft as when I bought them?

A friend of mine who runs an aircraft restoration business (and uses a lot of nasty stuff; MEK, Xylol, lacquer thinner) told me of a principle in chemistry that addresses the cleaning of brushes and containers. I wish I could remember the name of that principle and the specifics, but basically it says that some large percentage of material is dissolved and taken into solution in the first cleaning, and that a similarly large percentage is done so in each subsequent cleaning. By the time you have cleaned three times, assuming you get 80% of the solids each time, you have removed a huge percentage—like 99%; of the waste.

I pour the fresh spirits into a container, and rinse the brush out vigorously. I then drain the contaminated spirits into my settling container, and pour a fresh batch of spirits into the container (I do a little rinse of the container first). I vigorously rinse the brush again, and discard the spirits again. Rinse the container, and then rinse the brush with fresh spirits a third time. By fresh, I mean clean. The decanted spirits mentioned above are fine. By the way, for some reason, mineral spirits smells different after it has been decanted. I don't know why.

That should do it. In your case (stiff brushes), I would suggest that you may not be rinsing vigorously enough (I work the bristles pretty agressively with my fingers), you may not be using clean spirits each time, and/or you may not be cleaning enough times.

Later on in the same thread, the subject of brush spinners came up. I posted;

I was standing in the checkout line at HD last year with brush spinner in hand, and a fellow with paint spattered coveralls was waiting ahead of me.

He said to me, “you don't need that. Just spin the brush between your hands (like a Boy Scout spinning a stick to make fire).”

I replied, “actually, I was buying it to spin paint roller covers.”

He laughed and said, “for that money ($18, or so) it isn't worth it. Just toss the covers. They're only a couple of bucks apiece, anyway.”

I thought for a moment. I had already started using the plastic tray liners and tossing them instead of cleaning them for ten minutes. Then I paraphrased my old adage: do what the pros do. I took the spinner back to paints and bought a bunch of $2 covers. I've never been so happy with the extra time I have, and the lack of a sore back standing over a sink and spraying everything in sight. Like my pants.

Nope, I say. Save your money. Spin 'em by hand. And, the proof is in the pudding. I bought about $80 worth of Purdy brushes last year at HD before doing all the trim and sash painting on the house, and they could almost be returned for cash. Which I wouldn't do.


Last updated: 27 January 2009

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