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walden
02-13-2002, 10:47 AM
Looking at the prices of damar and re-touch varnishes, I notice that the large bottles are MUCH more economical per ounce than the small bottles. I haven't been oil painting for long, but I expect to be using quite a bit of one or the other, both for varnishing completed paintings and for use in mediums. However, I don't really know how far an ounce goes, so I guess I'll figure that out with experience. Questions:

1) Do these products have a limited shelf life? Should they be kept under certain conditions-- i.e., in the dark, or in the light?

2) Is one brand better than another? Are there differences in viscosity, color, other quality considerations?

3) When mixing either with a solvent, is it better to use turpentine, or mineral spirits, or does it matter? What about products like Turpenoid (not the Turpenoid Natural)-- is that ok?

Thank you!

Scott Methvin
02-13-2002, 11:37 AM
Looking at the prices of damar and re-touch varnishes...

1) Do these products have a limited shelf life? Should they be kept under certain conditions-- i.e., in the dark, or in the light?

2) Is one brand better than another? Are there differences in viscosity, color, other quality considerations?

3) When mixing either with a solvent, is it better to use turpentine, or mineral spirits, or does it matter? What about products like Turpenoid (not the Turpenoid Natural)-- is that ok?

Thank you!
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Real dammar varnish should have an extremely long shelf life. It is basically tree sap mixed with terpentine. You can also buy the dammar in it's raw "crystalized" form and make it yourself.
Light and dark should not make a difference, unless there is heat, which would not be desirable.

Use good terpentine only. It will perform as designed (removable)and dry correctly.

I recomend buying either premade dammar varnish from Kremer or buying the crystals and terpentine and making it yourself. You can also add beeswax and make a more matte version.

If you don't want to go to all the trouble, get the spray can version that contains pure dammar and terpentine.(Grumbacher, I think)
Good luck