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martha gamblin
08-15-2001, 03:12 PM
Dear Wet Canvas Participants:

I agree with those of you who have expressed your view that this thread should be dropped in favor of ideas rather than people.

Because my name is on this thread I'd like to just add some comments to clarify a few things. I apologize that this message is so long but it will be only post I will be making. Part of my job is to answer the technical questions that come in through the web site so I have no more time for web typing.

I have noticed that some artists have found it easy to dismiss our ideas because they are become defensive about their studio practices. That's fine just don't shoot the messenger!

Artist's color manufacturers like ourselves have very primitive tools to use for testing. We can do dry times, flexibility tests, primitive adhesion tests, etc. But our abilities are child's play compared to what conservation science is beginning to tell us. We are living in an important time in painting history. In recent years the most sophisticated tools of science are being applied to artists materials and paintings for the first time.

Just like most painters, I started art school knowing nothing. My first materials question was, "Why is this black if it is labeled Ivory?" I started by leaning what is in the literature: Doerner, Mayer, Whelte, etc. Then in 1989 I started forming relationships with conservation scientists and found that some traditional materials can be replaced with more stable alternatives and that certain studio practices can be replaced with safer ones.

So cut a long story short, Martha and I decided that our company should provide a missing link. We would be the company to bring to the studio artist the new knowledge from conservation science. Also from this new knowledge, we would bring products to market that take advantage of that new understanding (Galkyd, Gamvar, PVA Sizing, Mineral vs Modern Pigments).

So for the issues that we get the most resistance to, here are the sources:

Stop using natural resins in mediums and varnishes:

The Head of Conservation Science at the National Gallery says that natural resins are the least stable of artists materials. He did the research and formulation upon which Gamvar is based.

Stop using turpentine and move to odorless mineral spirits:

This information comes right off the various materials safety data sheets (MSDS). Painters can understand what permissible exposure levels are, plus you can do your own simple evaporation rate testing. If you think we are controversial on this issues you should check out ACTS.

Alternatives to lead:
Titanium is more inert than lead, so it is an excellent substitute and non toxic. We make a Flake White Replacement that has lead's working properties, similar opacity, tinting strength, weight, etc, but has no lead in it. And you don't have to deal with getting rid of the waste responsibly. If you use lead because you think it ages better than Titanium you should go through the museum's collection of oil paintings from the 1600 to 1900 and try to count the cracks in the lead. You will quickly overload your calculator. It is true much of that cracking is caused by Rabbit Skin Glue expanding and contracting but the lead gives way . . . much of it because of the issue of lean paint films. Martha has already sent you the information.

Robert Gamblin
[email protected]

Mario
08-15-2001, 04:16 PM
OK Robert, thanks for the kick off, but hang in there already......answer any questions as they come up here...this is not an antagonistic forum and you can sell a lot of paint here...so what's a little typing? Be brief and to the point. Who knows, you might actually enjoy your experience here...and I hope that you do.

Titanium
08-16-2001, 09:01 AM
Dru ,

I too would like some clarification for .

Heaton's - Outlines of Paint Technology -1948
pg 86 -

Titanium Dioxide is listed as giving a paint
that , " shows Excessive ELASTICITY on drying "

So a combination with Zinc Oxide [ brittle film ]
makes sense . Also mentioned on page 86 .

Somehow today , everyone keeps saying Titanium
in oil produces a Brittle dry ------ HUH ???????

There are presently 2 Titanium Dioxides offered
by Du Pont that are low in Oil Absorption -
one at 13. 5 and the other at 13.9 . The 13.9
is for exterior use. [ See TiPure on-line ]

Working off of a Lead White priming or Titanium / Zinc
Oxide / Barium Sulphate priming is not a problem if
you use Mars Colours and the above Ti02 [ 13.9 ] /
Zinc Oxide .

Alkyds - biggest problem natural ageing , all of the
tests are Artificial .

second problem , naturally too viscous , can not hold
enough pigment [ usually quietly modified - added oil ]

third problem - Type - Linseed Alkyds dry naturally , but
still yellow [ add on the low pigment load - possible
yellowing ?? ]
[ With time all oils yellow or brown , only the pigment
masks it . Pigment Rich / Oil poor ]

High Linoleic Oils , dry light , but as they oxidise they
to yellow . It's just that they take longer to oxidise.
So for Commercial Paint Companies this is a blessing .
Their paints are lower in pigment , with much filler .
Plus after 5 to 10 years your going to re-paint your
house anyway .
You can also add more driers to these paints and
probably won't see the effects until 50 to 100 years
later .

Low Yellowing oils - Safflower , Sunflower , Castor are
slow drying - driers needed to bring them up to speed .

Type used - Soybean , has to altered to dry , not a
natural drier .

fourth problem - not designed for Fine Art use .

fifth problem - Claims of elasticity - while adding in Stand
Oil .

Your probably better of , just adding in Stand Oil which
is time tested and the only real solution to Zinc Oxides
brittle film problem . Zinc Oxide will embrittle an Alkyd as
well .

The lead replacement works , I am using it presently
but I have never used Lead White , so I am also
missing nothing .
Titanium

Titanium
08-16-2001, 09:08 AM
Dru ,

one more .

Oil paintings generally crack or show age at 50 years+
give or take .

So it doesn't matter if your use Rutile Ti02 and Zinc
Oxide , or Lead White . Restoration is going to get you.

For greatest permanency , Enamel or Wax Painting on
a stiff support .

I believe we have a good deal of mixed information ,
Commercial and Fine Art . Lead White as a commercial
paint powdered / chalked after 8 to 10 years in your
Northern climate .
Titanium

Ymir
08-16-2001, 02:34 PM
Originally posted by Titanium



For greatest permanency , Enamel or Wax Painting on
a stiff support .


Titanium

Titanium, what's enamel?

Titanium
08-16-2001, 02:42 PM
Ymir ,

sorry about that - Porcelain Enamels
Vitreous enamels . Pigment bound by glass .

Mayer speaks of enamels in his book .
Titanium