First a quick reminder of impasto. To quote Wikipedia “Impasto is a technique used in painting, where paint is laid on an area of the surface in very thick layers, usually thick enough that the brush or painting-knife strokes are visible. Paint can also be mixed right on the canvas. When dry, impasto provides texture; the paint appears to be coming out of the canvas.”
What if you want to add more texture through additives not just for impasto work but generally. Oils as well as acrylics are the best to use for impasto work and you can thicken acrylics with a variety of gels, gesso, flour, plaster of Paris, PVA glue, even sand and very fine grit for more texture. Referring back to Tuesday’s watering down blog I can think of no reason why you can’t use sand or grit not just with water but with acrylic flow improver for texture or indeed for acrylic pour work too.
It’s never my intention to cover all options, I simply never have the time and I doubt if anyone does so never forget to explore the internet as frankly there seems to be few things you can’t add to acrylic paint to make it do extraordinary things. Just be sure to ensure you’ll remain safe before starting given there are often chemicals involved. What you can’t mix or is difficult to mix with acrylics you can sometimes use as a layer instead. Varnishes and bitumen, and all manner of resistant substances fall into that category.
There are too subtractives, like paint thinners and nail polish remover which can not only serve to rescue something but also act as a drawing or textural effect. Never dive in if your unsure, do a tiny blob of a test to see what happens first. I can never stress that enough. The fact is your safety is your responsibility as I can never be responsible for what others actually choose to do. In a world which has become litigation happy, I think it worth mentioning. I fail to see the attraction as surely litigation is a very stressful process so really should be reserved as a last resort. But I digress; moving on…