Resources for Old Master Material Methodologies

http://www.tadspurgeon.com/
http://calcitesunoil.com/

Check out both these sites they have some information that the professional painter and visual researcher who is interested in materiality will find valuable.

Rabbit Skin Glue as a Size

• 1 v of glue to 10 v of cold water
• [if adding alum, which will make the size waterproof, use 1 v of glue to 8 v of cold water
• [approx 5grms of alum to 2 v's of water]  the extra 2 v's of water can be added to the alum, which can be added to the glue after it has set and is in the process of being heated. 
• Dissolve the glue with the cold water - gently disperse with you hands [wear plastic gloves]
• Set over night -[ it should look like apple crumble when set]
• I use a rice cooker to cook my glue - put on to heat - do not let the glue boil - it should be heated to around 60 degrees [ you should still be able to put your finger in]
• The glue should last around a week if refrigerated

Rabbit Skin Glue Gesso -courtesy of Pablo Tapia

Using Rabbit Skin Glue Size as a base - heat till warm:
1 volume = 250ml
 
1 volume of glue to 1 volume of calcite [* you can add 1/3 v of Titanium White to the calcite: 2/3 calcite – 1/3 TW]
 Add the dry materials to the warm glue and mix well until blended
Once the gesso has reached a creamy solution add approximately one teaspoon of glycerine to the gesso – this well reduce the porosity of the gesso, as it is very absorbent.
 
*When applying the gesso ensure to apply a coat to the back of your board to avoid warping – apply between 4 and 12 coats of Gesso – smooth the surface with a pad of muslin that is damp  – apply using a circular motion.

*To seal the gesso ground you can do one of three things:
 

• Apply to coats of skim milk sequentially [a third coat with pigment added would act as an imprimatura]
• Apply one coat of Rabbit Skin Glue Size in the volume of 1-30 [weak]
• Apply Linseed oil repeatedly until the surface cannot absorb any more oil.