Portrait Artist Forum - Painting Over Dried Painting

Claudemir, thanks for smiling. I meant to be neither flippant nor combative, and didn't have a lot of time yesterday.

On the subject of damar, I'd be obliged to know your specific concerns for its yellowing, and experiences with that. I'm guessing that the climate where you live is tropical, and perhaps quite humid (?) which definitely could be a source of observations very different from my own.

It's my belief that a lot of what passses into the lore of painting materials and methods can be greatly influenced by climatic and ambient conditions that are never noted, as if we all lived and worked under the same conditions.

It's almost always a mistake to make unqualified statements about materials and their properties. Especially with natural resins, oils and solvents, their source of origin, quality, and methods of preparation are all variables that obtain even before one opens the question of the wide variety of possible working applications.

Why I feel that high quality damar (Singapore, if you can get it) cut with pure spirits of gum turpentine (the real thing, not the creosote-reeking stumps 'n' limbs juice one commonly finds these days) is not particularly a problem for causing yellowing is that through the course of 35 years as a sign maker and illustrator, I have used damar varnish to mock such glass crafting techniques as glue-chipping and etching in producing gold leaf signage on storefront windows. Damar applies water-clear, and has generally remained so in a number of projects and inscriptions now over twenty years old.

Also, I retain a number of my father's paintings, some of which are now nearing 70 years old. Having learned painting methods at his elbow, I can attest that damar was used to some extent in all of them both as a retouching varnish, and as a final varnish. None are yellowing, changing or darkening to any perceptible extent.

That said, all were painted, and have remained, in this high altitude, low relative humidity, temperate climate, and have been well-housed and cared for.

Forgive me for going into such detail, but if one is either to dismiss or defend a particular material, I feel obligated to offer reasonable substantiation for the claim.

Happy Thanksgiving Day to one and all!