Best type of soap for paintbrushes?

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LizzardBlizzard

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I'm just getting into soap making (hello world!) And I wanted to ask opinions on the best kind of cp soap to make to wash paintbrushes used for watercolor or acrylic painting. Most resources I've found have recommended a mild unscented soap, so I was thinking of making castile soap maybe? Ideally whatever soap I make wouldn't strip a natural haired brush of its oils, and wouldn't corrode metal or eat away at the glue holding the bristles in the brush.
 
I think it's better to ask another informed artist. There are natural and synthetic brushes and lye soap (liquid or bar) has a high pH which might cause problems (like it does to human and dog hair). It may be better to use a detergent type of soap, with a neutral pH.
 
I think it's better to ask another informed artist. There are natural and synthetic brushes and lye soap (liquid or bar) has a high pH which might cause problems (like it does to human and dog hair). It may be better to use a detergent type of soap, with a neutral pH.
I've had a couple of art teachers recommend simple white unscented bar soap, and I've also seen castile soap on the market on artist websites for sure, but you're definitely onto something of it harms the natural fibers over time. I'm in information gathering mode so if I was looking for more info on making a neutral detergent soap, would I be looking more into like shampoo bars? Or would it likely need to be a liquid soap?
 
If you want to make a pH neutral soap, then it won't be a lye (sodium or potassium hydroxide) based soap. You will need to use surfactants only. There are suppliers you can purchase from, plus free and professionally designed recipes for detergent bars.

When your teachers suggested a plain white bar of soap - they didn't realize that most soap in the grocery store is usually a syndet soap - a mix of true soap and detergent. There are very few true soaps (lye based soaps) sold in stores unless they have a section for "artisan" soap. So...likely they were using a pH balanced or neutral soap for their brushes.

Castile soap is a lye based soap, and will have a high pH....no matter how gentle the manufacturer claims the soap is.

And not to confuse things more, but there are BOTH lye based and detergent/surfactant based shampoo bars! Detergent bars are not difficult to make and websites like Humblebee and Me, Simple Sulfate-Free Shampoo Bar - Humblebee & Me. and Point of Interest – The home of SwiftCraftyMonkey Formulating Inc.! Join Susan as she obsesses about cosmetic chemistry and other things (some possibly related to monkeys). Often strange, occasionally useful, and always worth a stop as a point of interest on your journey through the Intertron.. are great and trusted sources of information. (I actually love using detergent shampoo bars for showering too).

Hope this helps!
 
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