I have been using my trusty Air Pen Pro, (not the same as the regular Air Pen which I am told is not very good), to apply Resistad to 4 silk paintings. The Air Pen Pro is great for people with arthritis in their hands.
The day before I mix my Dupont noir/black dye with some Resistad (about 50/50) and I let it thicken over night. Resistad is available from Procolour in NZ: Procolour Website
Then I gather all of my Air Pen Pro accessories and fill the applicator with the Resistad that has been colored with the Dupont noir dye
This last relapse I had left my hands pretty weak so I needed to go back to wearing my compression gloves and my lines were a little more wiggly but then again my customers are always telling me that the wiggly, whimsical nature of my paintings is what draws them to my work. So that may be a good thing ;~)
After the resist has been applied to the silk and it is left in the stretchers until the resist is dry.
Once the resist is dry I remove the silk from the stretchers and hang it on the line for safe keeping overnight. Tomorrow I will steam the silk to set the black Dupont dye in the resist. The steaming process will also activate the holding properties of the Resistad. Steaming creates more of a wax-like resist than heat setting with an iron does, however some people also get remarkable results by just heat setting with an iron. The alcohol in the Dupont dye is very caustic to the Resistad so steam setting it works best for me. Another bonus to batch steam setting the resisted silk is that I can roll them all up pop them in the steamer for 1-1/2 hours and go onto working on something else. I can't imagine standing over all of these paintings ironing each and every line until it is properly heat set.