Vaseline Is Bad For Your Brushes!
Since the 1980s, my family has used Vaseline as their go-to brush preservative in between jobs to keep the bristles of their brushes in the best condition possible and stop paint from drying in the heel of the lettering quill, which would effectively render the brush dead. But here’s the thing, (well, two things): Vaseline is hard to fully get out of your brush, and if enough of it contaminates your paint, it’ll dull it.
How can I sound so confident about that when many a sign painter recommends and uses Vaseline/petroleum jelly regularly with no issue? On one hand, just because something hasn’t caused someone else a problem doesn’t mean it’s the optimal solution but simply put, I can say that because I tested it.
What IS Petroleum Jelly?
Like mineral oil, petroleum jelly is a by-product of the oil industry. However, unlike mineral oil, it has one little tricky component that most people aren’t aware of. Vaseline, probably the most well-known petroleum jelly manufacturer, states on its website, “Petroleum jelly is a mixture of natural waxes and mineral oils…” Did anyone else notice waxes? The bane of all sign writers, second only to silicone? It’s right there in the making of the stuff, and we’re just slathering it all up and down on our beloved bristles? No thank you, sir!
How Easily Does Petroleum Jelly or Vaseline Dissolve in Solvents?
It doesn’t.
Not. At. All. Or at least, not without an absurd amount of stirring and patience compared to the other common brush preservatives. In one experiment I conducted that involved taking a wooden stir stick with a glob of Vaseline on the end and trying to dissolve it in a cup of mineral spirits through stirring, it took over 5 minutes before I just gave up. Sure, the glob had smoothed over and reduced in volume by half, but it was not making me confident in the ability of sign shop solvents to quickly clean petroleum jelly from a lettering quill’s bristles.
If you’re a visual person like myself, I have a short video showing how little effect solvents have on petroleum jelly here.
Is Vaseline Any Good for Sign Shops?
Yes! I still think Vaseline or petroleum jelly has its place and uses in any sign writer’s kit. It’s a great option for protecting those brushes you know for a fact you seldom use. You know, the non-workhorses that are neglectfully lying in some obscure box or corner somewhere - those. Vaseline can keep them from drying out for a long time until you use them again, but now you know when that time comes, you’ll need to spend much longer than you normally do cleaning the brush before it touches the paint.
Alternatives to Vaseline, Jelly, and Grease
If I’ve sold you on the idea that thick greases and jellies may not be the miracle preservative and brush conditioner they’re touted to be, you’re probably asking yourself, “What else can I use, then?” One great option is to leave the brushes you use frequently in a shallow leak-proof tray of mineral spirits or baby oil. This ensures the brushes cannot dry out, and both oils dissolve pretty quickly in mineral spirits or turpentine. Bonus information: I have video proof that your paint can take a pretty generous amount of contamination by either of these oils and still work. Check that video out here.
If leaving your brushes in a small pool of oil is prohibitive to your workflow, or there’s a danger of said pool attracting dust/dirt/debris, you can still soak your brushes in some mineral oil before gently wiping away the excess and storing your brushes in your sign kit or brush box. I’d add that it’s a good practice to check in on your unused brushes every 4-6 months and make sure that they’re still well-saturated with oil. You could even sync up this “oil change” with the regular service on your car - just DON’T USE the oil FROM your car. ;)
