This time around, I mixed the gesso with a variety of 'additives'.
This is a victim of another one of my brainstorms. Recipe: 4 drops white gesso, 1 drop Reaper Master Series Brush-on primer, 2 drops 5% Flow-Aid. I thought the primer in the mix would help, but the bubbles remained. The figure is a 25mm GZG Kra'Vak (please note that GZG is in no way responsible for this mess!).
These two are much better. Recipe: 4 drops white gesso, 1 drop Delta Ceramcoat black, 2 drops 5% Flow-Aid. There is still a bit of bubbling, but it is rather minor. The grey color is nice; it reminds me of the first minis I painted - GHQ micro-armour. At that time I was using Floquil enamels... awesome coverage, but I'm certain that the odor would knock me flat nowadays. (2 more GZG Kra'Vak)
Success?!? Recipe: 5 drops white gesso, 1 drop Delta Ceramcoat black, 3 drops 5% Flow-Aid. This one came out nicely, no bubbling. (I do wonder how of much of that is technique versus mixture.) The coating seems to retain the paint-holding texture and the detail-saving shrinkage of gesso, and I can easily cope with the grey. (25mm GZG New Israeli [I think?] )
Right now, I'm pleased with this recipe.