MITRA Forum Question Details

Hi Paul.

This or similar subjects have been brought up many times here on MITRA. Please search to find the salient threads. Truth be told, I am not an advocate of sealing in or fixing underdrawing materials beneath oil paint layers unless there are specific effects that the artist intends on having visible in the final image. Layers like these invariable add an incongruous and unsympathetic layer, which will react differently to movements and changes in environment than the oil layers beneath and above it.

If this effect is necessary for the aesthetic vision, I suggest a minuscule thin application of an alkyd/insoluble stable material layer above the drawing. This is one of your mentioned options but even this is not without problems. The resulting coating will be both glossier and more gummy/flexible than the ground beneath it but will likely be fatter or more flexible than the layers applied upon it.

One of the reason that I usually balk at this general concept is that if you are worried that superimposing oil paint will smear the underdrawing, why do you think that the application of an “intermediate” layer will not? If oil paint will smear the underdrawings, so will a brush applied fixative/isolating coating. The only way to avoid this completely, or almost completely, is to apply the isolating material with a spray gun. If you do this, please follow all safety precautions and wear the appropriate equipment when spraying.

As to your proposed test of applying fixative 1-3 hours after oil painting, I am assuming that there are some omissions or typos here. One should allow oil paint to dry at least to the point where is can withstand the pressure of a fingernail before overpainting or applying any additional layers, no matter what these layers are. Three days is short, three hours is insignificant.