thanks for the info.
I wrote to Golden, here is there reply and my reply back.
o Is the gesso itself suddenly becoming pebbled, or is it the watercolor paint? If it is the watercolor paint, is it happening with just the paint of the latest layer? Is the pebbling a version of wet paint beading, or are bits of the watercolor layers cohering? Or is it something else? Do the pebbled areas of paint have their own height, or are they the same height as the paint film?
· Also, knowing more about how you are painting will help us understand what is happening.
o What is the panel made of and how was it prepared? Which gesso are you using, how many coats, and how was it applied? Was the surface sanded? How long a time passed between when the gesso was applied and when the watercolor painting began? What is the general humidity and temperature in the studio where this is being created?
· Which brand of watercolor, and are there any paints/pigments in particular that cause this phenomena? How many layers of glazing does it take for the pebbled texture to form? How diluted is the watercolor, and how large are the painted passages? While painting, is the painting flat (allowing that paint to puddle in one place while drying) or slightly tilted? Are you using any watercolor mediums or additives?
General thoughts on watercolor over gesso:
· Because watercolor by nature has a low binder to pigment ratio, the texture and absorbency of the surface upon which it is painted plays an important role in paint adhesion. With watercolor paper, the absorbency and fibers combine to help hold the paint to the surface. Acrylic gesso is much less absorbent than watercolor paper, and beading and paint lift can easily happen while painting upon a gessoed surface with watercolor. And because watercolor’s adhesion to gesso is not very strong, it is also possible (if rare) for dried watercolor to flake off of gesso. One possibility for the future is to put a thin layer of an absorbent ground down over the gesso to create a more watercolor-friendly surface. Among our products, possibilities include GOLDEN Absorbent Ground or QoR Watercolor Ground, Golden Light Molding Paste or QoR Light Dimensional Ground, and Golden Fiber Paste or QoR Cold Pressed Ground. The last pair would be the most textured among these products.
o QoR Grounds: http://www.qorcolors.com/groundsapp
Preserving painted passages while the watercolor painting continues to evolve:
· Removable masking fluid or liquid frisket is an approach we have found successful for preserving a painted area as is, while continuing to paint. Be aware that liquid frisket ruins brushes. And it is a good idea to always test the masking fluid with the support and process being used to be sure that the frisket will come up without problems, and without bringing an unacceptable amount of paint with it. The Incredible White Mask Liquid Frisket by Grafix has worked well in our tests.
· As far as painting or spraying an acrylic medium over watercolor as a permanent mask to preserve areas from over painting, this is not something we have tested. Thin liquidly matte products would work better than the thicker or glossy ones, so Fluid Matte Medium might be an option. However, watercolors are likely to have the same type of adhesion issues with acrylic mediums that they have with acrylic gesso.
Beading:
· Ox Gall or QoR Synthetic Ox Gall can help forestall beading when added to diluted watercolor paint painted onto paper. However, the paint applied over it is likely to bead unless it has the same addition. We have not tried this on gesso, so if you find this of interest we would recommend testing first on sacrificial gessoed surfaces to be certain it works as needed within your process.
o QoR Synthetic Ox Gall: http://www.qorcolors.com/products/mediums-grounds/mediums
My reply:
When I paint watercolor on your prepared gesso board, I love the results, smooth, no beading. the paint does tend to lift more than I would like, hence my question about a “sealer” in the middle of a painting. so that a ground will not lift as I keep adding layers. (Perhaps on gessoboard the drying time between washes needs to be longer?) what do you think.
Watercolor paintings on wooden panels. I first used GAC200, then gesso. Then multiple sandings and spray gesso.
I think either I didnt wait long enough before adding (and lifting ) the watercolor and the water slowly eroded the gesso surface. Would you agree?
I have not decided that the surface must need the water absorbent ground. What dilution do you recommend for QoR absorbent ground? should that be sanded between coats,? I am after a very smooth surface.
Any comments are helpful.
.
