In February of 2017 we had the privilege of hosting Catherine and Robert Gamblin for a presentation and demonstration here at TALAS centered around Gamblin Conservation Colors and their Pigmented Resin Wax Sticks.
Robert spoke about the history of Gamblin Paints and how it all began in his garage 30+ years ago! Part of what makes Gamblin paints so unique is that they use Gambol, which is an odorless narrow cut mineral spirit.
In 1994 Robert Gamblin teamed up with Rene de la Rie, Mark Leonard, and Jill Whitten who were working to define the criteria for a new kind of conservation color. The key principles they were looking for were: stability, safety of use, quality of manufacture, and excellent optical and working properties. Together they developed the line of Gamblin Conservation Colors.
The low molecular weight resin binder in Gamblin Conservation Colors, attributed to the use of Gamvar or Regalrez 1094, make these paints have better optical properties and better handling properties than paints based on polymeric resin. High molecular weights cause more light on an image to scatter and colors appear less saturated.
Aldehyde Resin (Larapol A-81) was chosen as a more appropriate binder than some other low molecular weight resins because they are slightly polar and they wet pigments more easily. If you look at the refractive index of Larapol A-81 you will notice that it is quite similar to that of Linseed Oil or Damar Resin.
It is suggested by conservators to use Isopropanol (99% pure) such as “Everclear” or “Gemclear” or other 95% grain Alcohol CAS#64-17-5 with the Gamblin Conservation Colors.
It is also suggested to use 40% mineral spirits if the jars dry out over time. The benefit of a jar over a tube is that you can manage the solvents and reconstitute the pigments as they dry out with time. It is good practice to add a few drops of mineral spirits every time the jar is opened. This should help replenish any solvent that has evaporated.
The Pigmented Wax Resin (PWR) Sticks are a combination of: Beeswax, Microcrystalline Wax, Lightfast Pigment and Larapol A-81. Part of the beauty of this product is the shelf life, and its resistant to cracking over time. PWR is ideal for filling losses in paintings. The material is easy to manipulate using moderately heated tools such as the WhipMix. Cracks and other physical irregularities of an aged painting are easily replicated using dental tools (probe kit).
Because they do not ghost, PWR are well suited for dark colors and many cracks. The color range (available in sets) helps facilitate the process of matching paint, and the Gray Range set is great for photography.
Everyone at the presentation had a chance to demo the Pigmented Wax Resin Sticks – which was both fun and a great learning experience. We were able to see first hand the shifts in color based on the temperate at which the PWR was applied.
Catherine also showed us some silicone molds that were made to replicate the textures of various canvases. As the PWR can be reactivated using this mold is a cleaver way to impress a pattern and to camouflage the repair.
Thanks again for visiting Catherine and Robert Gamblin!
