paint reducer

Glycerin is often used as a substitute for propylene glycol, which could be a co-solvent and/or retarder.

Personally, I'd stay away from weird mixes & just use the manufacturer's own thinner. (Though if it was enamel, I'd be about 95% sure that plain old mineral spirits would be just fine)

Hi Steve5,

I use mostly craft acrylics and have seen several YouTube videos on home brew thinners. I have also tried a number of them including one which contained Fantastic Window Cleaner (not Windex), IPA, water and a drop of glycerin. The author claimed glycerin was a 'dispersant/detergent'. I've not heard of glycerin as a detergent but tried it anyway. Bottom line - Yes, I think a drop of Dawn dish washing liquid would work as well. Or just leave the glycerin out of the mix. Of the ones I've tried, the only advantage over branded thinner is cost. You can make a couple of quarts of home brew for the price of a 4 ounce bottle of X20A.

I bought a bottle of X20A two years ago. Since then I've built about 10 models and used about the half of X20A.  The cost of branded thinner is negligible.