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Question asked 2017-12-08 17:31:10 ...
Most recent comment 2023-12-31 21:03:19
Technical Art History
Oil Paint
Paint Mediums
Hi-
I'm rather old school and I can't afford to switch to walnut oil and lavender I have to keep it simple. I paint a lot and on a large scale. I would say my application of paint is on the wet loose side and most likely too much vehicle and medium is slapped around by your standards
As I get older I am concerned with my health, if it is not too late, so I have begun to rethink my formula of 40 years:
1:1:1
Turp- Dammar -Linseed oil
I begin with gum turp and progress to a fatter medium.
Occasionally I add stand oil to the brew.
I have experimented with adding egg yolk, using liquin and alkyd mediums. I'm happy with my old "go to" but for the fumes. I occasional remove dammar from the mix. Any ideas of a formula or medium that would suit me. Any big issues with the 1/3, 1/3, 1/3 mixture I use?
Thanks
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Moderator Answer
(mkinsey)
There are health risks associated with exposure to Pure Gum Spirits of Turpentine, including respiratory problems and allergy-like sensitivity. Many experienced painters with a long history of turpentine use have migrated to clean Odorless Mineral Spirits. This type of solvent is not completely without risk, but OMS does not induce materials sensitivity. OMS also evaporates at a slower rate than turpentine, so the buildup of vapor is not as rapid. Even high quality art supply brands of OMS are very economical. Of course, this is still not solvent-free painting. Also, the paint doesn't behave quite the same with OMS compared to turpentine.
Damar varnish also contains turpentine, so you may want to consider replacing that component of the medium with walnut alkyd medium or solvent-free alkyd gel. These do cost more than damar (especially homemade varnish) but they do offer very nice handling and drying properties without hydrocarbon solvents.
Another reason to consider replacing damar in your studio is that a paint film containing significant amounts of damar can remain soluble for a long time, making cleaning more problematic. Since you mention that you use large volumes of medium, solubility and other drawbacks of damar (e.g. darkening, embrittlement) may be a concern.
The vegetable oil components of your medium don't generally present any particular health risk. Linseed, stand, safflower, poppy and walnut oil are all free of hazardous vapors, though some do find the smell of linseed oil unpleasant. All drying oils (including cooking oils) can spontaneously combust from buildup of heat from oxidation, when oil-soaked rags are left balled up. Rags can be left flat to dry before disposal, or immersed in water in a lidded metal can.
Finally, when solvents are present in the studio, adequate ventilation is essential- there's no substitute. Make sure air is moved and replaced, not just moved around with a fan.
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Moderator Answer
(brian baade)
Hi
The medium you describe was used by many, many painters in
the 20th century and is identical to the medium Ralph Mayer
suggested for glazing in oils (although his recommendation contained cobalt
drier as well). Today this medium is not considered as benevolent as it was in
the past. The large percentage of soft dammar resin can contribute to a paint
film that is sensitive to the solvents used to remove degraded varnish in the
future. It also contributes a degree of brittleness to the paint. Stable
paintings can be made using such a medium but it would need to be added in very
small proportions as compared to the oil paint. In practice, this is unlikely
and it is best to avoid mediums that contain soft resins. Finally, the dammar is
the reason why you have required turpentine rather than a less noxious solvent
like a highly refined zero-aromatic odorless mineral spirits. Dammar is not
soluble in these solvents and requires either turpentine or a mixture with a
high proportion of aromatic hydrocarbons.
There are some other alternative
solvents but they tend to smell just as noxious during longer painting sessions.
Some of the claims of lower toxicity for some of these may actually simply be
the result that they have not been tested as extensively as the more common
diluents.
So, what you need is an oil medium that does not require
turpentine (or aromatic hydrocarbons) or soft resin. Stand oil diluted with a solvent is perfectly
fine in terms of stability. It may be less desirable in terms of paint
handling. It really depends on what you are after. I have found that this mixture
really levels paint strokes and can contribute a greasy effect rather quickly.
It is sticky without having the “feel” that your old medium had due to the
resin. Linseed oil and solvent is workable as well although its “feel” is also very
different from what you are used to.
I personally have not liked the handling
of gelled alkyd mediums but others really love them. I have found that the
fluid alkyd mediums more closely resemble the older mediums like the one you
describe. You may want to thin them with additional OMS if you use larger
amounts of medium as you suggest. You could even use one of these as a
component of a three-part medium by substituting the alkyd for the damar and
OMS for the turpentine. Finally, have you tried using any of the newer solvent
free oil mediums? A Google search should yield a number of these offered by
different manufacturers.
Sorry if this is a less than satisfactory answer. Perhaps
others here have a different or additional take on this issue.
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Moderator Answer
(brian baade)
Ha
Matthew, you posted while I was editing my post. Anyway, multiple voices are always better. Thanks for the commentary on the health issues. I had completely missed that in my response.
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Moderator Answer
(mkinsey)
Brian, We've been tripping over each other lately! I'm glad if I added something useful.
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