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Category: Lewis Conservation Services

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Protecting art damaged by Hurricane Harvey

Yesterday I received a note from a reader in La Porte, Texas, one of the areas hard hit by Hurricane Harvey. “Any tips on taking care of a wet oil painting? It is on a wood frame and is lying flat. We took it out of the large external wooden frame and it seems to be drying. There is not a backing on the canvas.”
Surf on Saco Bay, by Carol L. Douglas
I turned to Lauren R. Lewis of Lewis Conservation Services in S. Thomaston, ME, for an answer. Here is her advice:
As the flood waters recede and people return to what remains of their possessions, many difficult decisions need to be made and challenges will need to be addressed. While the first impulse would probably be to contact professionals to deal with your artwork, books, photographs and other keepsakes, local conservators will likely be overwhelmed with the amount that needs to be done.
Perhaps next you would turn to the internet, but I would encourage caution when reading advice on how to deal with your priceless possessions. There is much information on the web that might actually cause further damage. Where, then, should you turn for advice? I am attaching some articles, links, and practical advice that I hope will be helpful in your salvage efforts.
Take care of yourself first. Mold growth and toxins in the flood waters risk your health, so please use safety gear (gloves, respirator, etc.). This cannot be stressed enough.
Link to keeping yourself safe after a flood:
https://www.cdc.gov/disasters/hurricanes/cleanup-home.html
The most important first aid that can be given to flood damaged items is to remove any water and to dry them. Lay things flat, preferably on a moisture-wicking surface like blotter paper or even on a platform made of screening, so that air can reach top and bottom of the item. Use fans to move the air, but make sure there is no loose paint that might be lifted by air movement. The goal is slow, even drying. Don’t use hairdryers. Don’t try to flatten photographs before they are dry as the surfaces will be easily damaged when wet. Keep paintings on stretchers if possible so they dry with even tension.
Once the items are dry they can be reviewed by a conservator for further treatment.
National Heritage Responders is a group of conservators trained to deal with disasters. An article in Museum of Modern Art blog deals with contemporary paintings damaged in flood.
Stay safe and please share with anyone that could use this information!
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Better living through chemistry

Yes, the ‘fat over lean’ rule still pertains in oil painting.

Estuary Light, by Gwen Sylvester.
Gwen Sylvester’s Estuary Light, above, won this year’s Juror’s Choice Award at Wet Paint on the ‘Weskeag. It is a perfect application of acrylic paint: luminous, fluid, but not washed out into faux watercolor. The nominal subject—egrets—are just suggested in the midfield. 
Kay Sullivan and Gwen and I sat together to watch the auction. We are the last three years’ winners of the Juror’s Choice Award. The art world is one of the last strongholds of gender bias, intentional or not. To have three women winners in a row is an anomaly, and speaks well of this event.
A student at my workshop last week asked me whether the ‘fat over lean’ rule still applies now that we’re using odorless mineral spirits (OMS) instead of turpentine. It’s a great, complicated question. Turpentine is pine-tree essential oil. OMS are petroleum distillates. But before you rush back to using turpentine because it sounds “natural,” it is linked to a host of respiratory and other illnesses.
A lobster pound at Tenant’s Harbor, was my entry into Wet Paint on the ‘Weskeag.
I saw conservator Lauren Lewis at the auction. She told me the answer to Maureen’s question was still yes. That was all we had time for, so the rest of this explanation comes from the internet.
Solvents like OMS or turpentine dry through simple evaporation. The binder oils in paints are more complex; they cure by something called crosslink polymerization.
A polymer is a long chain formed by many little molecules that stick together. A crosslinked polymer network is a mesh of these chains that are woven together. Just as with fabric, woven threads are stronger than individual fibers. Crosslinked polymers can be very strong.
These crosslinked polymers also resist solvents better than simple chains. To dissolve a polymer, each of the long molecules must be surrounded by the solvent and dispersed. As the polymer gets larger and larger, it becomes more difficult to dissolve the polymer molecules.
Sometimes there are enough links to connect all of the polymer molecules into a single mesh.  When this happens, you can no longer dissolve the polymer molecules—they either float away as a single lump of paint or they don’t go at all.
You can’t reopen half-dry oil paints like you can half-dry acrylics. That’s because of crosslinked polymer chains.
Think about the last time you let your paint dry up on your palette. You can’t ‘open’ half-set oil paint like you can with partly-set acrylics. All the pigment is drawn into the lumps. That same tendency is what makes them so tough on the canvas, and why you want that oily layer on the surface.
Humidity often damages a paint film. This happens when water molecules surround the paint components and push them around. Crosslinks limit how much water can get into the film.
Speaking of humidity, I leave in a few minutes for Saranac Lake, NY, for the Adirondack Plein Air Festival. From there I go to Plein Air Plus in Long Beach Island, NJ. As I’m writing this, cool, damp air is rushing in my window. My house sits above Rockport harbor. The ocean is my air-conditioner. Why do I ever leave in the summer?