Making Acrylic Paint, additives

Making Acrylic paint is similar to making watercolor paint, pigment + binder = paint, pigment + binder + additives = thick paint.  But I wanted slow drying Acrylic paint  

In 2014, I experimented with the various products available then to slow down the drying time on the canvas, a gessoed piece of 140# watercolor paper, and have workability similar to oil paint.

I mixed Matisse brand vermilion with

1. Open thinner, it dried on the palette in 15 minutes and on the paper in 60 minutes
2. Liquidtex Slo-dry, a very liquid mixture that dried in 3 hours on the palette and 15 minutes on the paper
3. Liquidtex Flo-aide, 30 minutes on the palette, 15 minutes on the paper
4. Liquidtex wetting spray, 30 minutes on the palette and 15 minutes on the paper
5. Golden Retarder, 15 minutes on the palette and 3 hours on the paper
6. Golden GAC 100, 15 minutes on the palette and 30 minutes on the paper
7. Golden Acrylic Glazing, 15 minutes on the palette and 30 minutes on the paper
8. Golden Self-leveling medium, 15 minutes on the palette and 30 minutes on the paper
9. Golden Open Acrylic Gloss, 15 minutes on the palette and an hour-ish on the paper

I found no product that allowed me to keep it alive on the ground (gessoed paper).  Considering my experiment, I have to comment, but who cares?  Acrylic paint is a fast medium that can be easily painted over, it’s not oil paint.

In 2015, I experimented with mediums

1. I mixed GAC 100 with Gouache and a little extender and had a wonderful paint
2. Dr. Martin’s pigment with Golden Open and extender makes a thin, very liquid, paint
3. Powdered pigment and Golden Open and extender makes a thin transparent pigment.  I felt that I should have continued and added more dry pigment to the mixture
4. GAC 100 plus Open Mat Medium and Gouache makes a wonderful paint, it will stay alive on a Stay Wet Palette 4 hours then begins to become Cottage Cheesy
5. GAC 100 plus dry pigment will stay alive for 6 hours on a stay wet palette and hardens at 7 hours
6. Dry pigment plus GAC 100 plus Windsor Newton Slow Dry is the winner

The Windsor Newton formula was clearly the winner (#6 above), but I reiterate what’s the point, this is not oil paint.  Acrylic painting is faster than oil painting.  If you want to mix paint of work on a lorge surface for a considerable length of time use a Stay-Wet palette.  I’ve had acrylic paint mixtures stay alive for weeks on the palette.  Over time the paint begins to smell.