Acrylic Isolation Coat

I would not experiment with other media but any high quality acrylic dispersion medium should work. You would want it to flow, so very heavy gels are probably not the best choice. Acrylic dispersion paints are not my forte but I might add a bit of flow releaser (no more than suggested by the manufacturer) to facilitate brushing and flow. I would stay away from matt mediums as they tend to make films that are more permeable.

​Hi – Let me chime in, especially as Golden is generally the most closely associated with the recommendation of an isolation coat. Essentially any clear continuous gloss acrylic coating that you can apply that works for you will work as an isolation coat. The only reason we recommend using our Soft Gel Gloss is that, by a quirk of its own formulation, it has the best anti-foaming property of any of our products once it is thinned with water to a brushable consistency. Plus the water helps with both flow and leveling. That said, we have had people use any number of alternatives which they have developed their own technique around. So definitely feel free to try other things – just be careful of foam and brushstroke texture, as this is a permanent coating that cannot be reversed. Because of that, we try to stress to people – even with our own Soft Gel recipe – to practice practice practice on less precious pieces or test canvases before using on a finished work that has real value or meaning to you. Like anything, applying an isolation coat, as well as a varnish, is a skill that takes time to master and do well. I say all this because we rarely ‘learn’ to varnish or apply these types of final coatings while we are learning to paint, so by the time we embark on it, we are usually beginning to show or create work we like and want to protect. On one hand we have spent years honing our skills as a painter, but can forget that we are still a relative beginner when it comes to mastering these types of applications.

On a final note, I would be cautious and less likely to recommend the use of a flow release. At least in terms of ours, which we recently renamed Wetting Agent, it is a highly concentrated surfactant meant solely to break water tension and used especially when doing staining or working directly on fabrics. It tends to be one of the more misused of our products, and if you decide to try it, you should first thin it 1:10 – 1:20 with water, and then of that diluted mix, add no more than 3% into any blend. Going higher risks generating excessive foam and in our experience, unless you are truly having wetting-out issues related to surface tension, just adds unnecessary complications. If you find you need more flow and leveling, just adding water is usually enough, or opt for a thinner more fluid acrylic medium to begin with.