U of S | Mailing List Archive | alt-photo-process-l | Re: gesso for watercolor?

Re: gesso for watercolor?


I don't think the "lascaux" gesso is much different than any other acrylic
gessoes you'll find in the market. It says "acrylic resin dispersion +
titanium dioxide + mineral based extenders", they're not mentioning any
other filler (usually calcium carbonate - to make it more absorbent) and
also they don't say "it's suitable for watercolor". (Only egg-tempera, oil
and acrylics are listed in the product sheet. I don't see the need / point
of using acrylic gesso for watercolor painting BTW; it's contradictory to
my understanting of the medium!) So, I don't think you'll have better
performance than other brands, unless you do "something" to make it
suitable for gum printing.

Try this: purchase the cheapest acrylic gesso you can get (I mean real
cheap here!), and mix some calcium carbonate powder (or marble dust) into
it, and apply this onto the surface (BTW, stick with good old gelatin if
your intention is to print on paper!) then size. That's it. I'm sure Keith
will provide more options and thoughts as I learned this from him -> he
has far more (superior) experience than I have.

My formula is as following:

a) 1 part acrylic gesso, b) 2 parts calcium carbonate powder, c) 2 parts
water (all by weight)

Put b into a, mix well (really well - thoroughly, as much as homogeneous
as it could get) then add c in small portions (still stirring, just like
making mayonnaise), filter throuth cheesecloth (if you feel it's too rough
and there are clumps), apply onto surface in thin and even coatings in
perpendicular order (using a brush or foam roller), drying each layer with
a hairdryer. You may want to sand between each layer or the last layer or
no sanding at all. Then size with 1.5% (or more depending on your
experience) hardened gelatin.

Fiddle with calcium carbonate amnt. (and sizing strenght) to increase /
decrease tooth / absorption, fiddle with water amount to find a
consistency you're comfortable to work with.


16 Mart 2009, Pazartesi, 9:14 pm tarihinde, Katharine Thayer yazmış:
> ...
> Recently Keith Gerling and Loris Medici traded observations about
> gesso in various combinations as a sub for gum on wood and on
> aluminum ; you should be able to find that thread in the recent archives
> http://www.usask.ca/lists/alt-photo-process-l/
> or maybe they'll chime in to answer here.
> Katharine
> On Mar 16, 2009, at 9:48 AM, phritz phantom wrote:
>> is this stuff the same as acrylic gesso/primer?
>> i've used acrylic before and the results were ugly: flaking, very
>> greyish... allover not pleasant. at all dilutions.also sometimes
>> the emulsion seems to go very deep into the size, so the prints
>> could really take a strong brushing without the emulsion coming
>> off.  mixing it with gelatine helped a little, but still not as
>> good as pure gelatin or no size at all.
>> now (i still have almost a whole bucket of acrylic gesso left...a
>> 500ml was the smallest size) i've found out that acrylic primer is
>> not suited fot watercolor pigments. i should read labels before
>> buying. but i found a gesso which is suited for watercolor, it's
>> lascaux gesso. but before i spend money on half a liter of stuff
>> that doesn't work either, has anyone ever tried this product?
>> here's a link to the datasheet:
>> http://www.lascaux.ch/pdf/en/produkte/malhilfen/impraeg_grund/
>> 52305.02_grundierungen_.pdf
>> phritz