blending inside 3D shapes in acrylic paints

Q & A

Q. Would it be easier to blend if I used a retarder medium with my acrylic paints or interactive acrylics?

A. Interactive acrylics offer ‘fast' and ‘slow’ mediums to add, as the pigment itself from the tube does not cure without adding some kind of medium to bind it, hence you can choose (according to their instructions) to make it dry faster or slower according to the liquid medium added. 

GLYCERIN is added to the slow medium (the same chemical used in retarder mediums which can be used with regular acrylic paint to slow its drying time). In my testing of these products, I found that the tackiness that happens in the drying phase feels nothing like blending in oils and becomes a negative compared to simply spray misting lightly with water while blending an area. 

Another irritating aspect of the interactive products was that students invariably turned up to class after having been sold the incorrect medium or none, (I don’t believe that the manufacturers or shop owners provide adequate training on the difference)  so these tubes get mixed in with regular acrylics and are simply not going to cure properly without the correct mediums, rendering their use more of a problem than a solution.

Q. I can’t get my shapes to look like these in the video when I try to blend

A. In the early stages of learning painting, sometimes the disappointment all comes down to not having enough drawing practice. There is a lot to be gained by opening up new neural pathways (nerve connections between the eyes, hand and brain) through drawing.

If you are not able to get an accurate drawing to work with, all the perfect blending in the world will not give the intended result when 3d modelling subjects in paint. Spend as much time as you can on the Fundamental Drawing Crouse, (repetition is the mother of skill) you will gradually train your brain/eye/hand team to translate lines, shapes, spaces, angles, proportions, values and textures.

Q. How do I blend if I want to use thick impasto acrylic layers?

A. There are many ways of creating a blended look in paint. If you are wanting a blended look with impasto layers, you are better off aiming for an “optical blend”, because a smooth physical blend of the paint is not possible while staying thick with the layer of paint. By optical blending, I mean that the tones or colour shapes are intermingled at their borders with gentle knifing or brushing back and forth, so that one leads into the other gradually.

Building broken layers, allowing previous layers to show through, or scumbling layer over layer are two other ways of creating an ‘optical blend’ rather than a physical blending of paint.

Scumbled layers

Scumbling is possible in watercolours, acrylic, oils, and pastel. It involves, scantily loading the brush and drawing paint across a somewhat textured under-layer, in order to give a broken effect, or show something of what is underneath.

‘Optical blending’ can be achieved as well with scumbling, by subtle overlaying and feathering, whereas in physical blending the two adjacent hues or values of paint are actually physically blended.

Thick ‘impasto’ paint