Friday, November 6, 2009

More about drying.

Grave stones, Lanes Island, Vinalhaven, ME.

There that's as good as anything else for a picture. I like always to post a picture at the head of each post, and I have been making a point of showing more New England scenes, I have shot so many.

In the comments I was asked about painting gel, Neo-Meglip in particular. That is something I have not used much. Meglipo is an old gel that was made with litharge a form of lead that is cookeed in oil. It is part of the Maroger system of painting that was espoused until recently by the late Frank Mason. Because of the toxicity associated with its manufacture and the marvelous handling qualities it imparts, Gamblin has made a substitute that is alkyd based. I have tried it, and I don't see any reason why if you like it, you should shy away from it. I do not recommend the real Marogers. I am going to catch flack from the folks out there who swear by the stuff and I am perfectly happy for them to use it. I won't.

One of the additives that accelerates the drying of paint is lead. It used to be added to house paints and all sorts of things to make them dry. The same is true if you are using lead as your white, you will get faster drying times. I used to mix a small amount of lead into my white for just this reason, particularly when I was traveling. There is an interesting alkyd flake lead made by Winsor- Newton which is in their Griffin line of alkyd paints.

The Umbers and Siennas dry quickly too. If you want faster drying these are a good addition to your palette. Particularly if you don't want to use lead or an alkyd medium. Watch the paints on your palette. I don't clean them off my palette every night, I leave them and clean the field in the middle. Notice which ones seem to dry out the soonest and those which seem to never dry.

The ultramarine and viridian, pthalos and ivory black dry a little slower but they do dry reliably.
The viridian tends to grit up a bit on the palette and I have discussed this problem before. The transparent reds, quinacridone and alizirin are the slowest drying. The alizirin is so slow and unpredictable that I advise you no longer use it and switch to the newer permanent alizirins, which are quinacridiones.

I was asked in the comments about drying paintings in the sun and whether I thought that was OK. I should point out that I am not a chemist, and I am not a real stickler on the materials, I do what works. The responsibility level changes when I am advising hundreds of you on something like this. So I should say, "well I do it!" and let you decide for yourself. It is easy for an art materials supplier or a magazine art expert to say "don't do x" It is safe for them to say no, they can't possibly get into trouble. Lawyers do that too. In the real world though within reason you do what works, because the art has to get made and out the door. I also look at how things seem to have been done in the past.

There is an exception to that, and oddly enough it concerns a pigment that never really dried. In the 19th century there was a fad for a pigment called bitumin. It was an asphaltum, a tarry brown goo made into an oil paint that gave a warm glow to paintings and gave them a Rembrandty dirty varnish kind of color. In the time that was much appreciated . Paintings, made with bitumin have had all sorts of problems, they have bubbled, the bitumin has moved about under other colors and come to the surface in some areas. It gets liquid again in the heat and causes other colors above it to crawl or "alligator" No one to my knowledge uses this stuff any more, It did used to be available when I was a kid and I tried to make some old timey looking paintings with it in my "Dutch " phase. I saw one of those old paintings of mine from the early 70's not too long ago and it looked OK, but I wonder if someday it will weep hydrocarbons from its surface. They can put a pan under it.

Here is tonight's weird little factoid. When the American Luminist painters like Sanford Gifford and others went to paint in the American West, they carried black iron boxes. The put their fresh paintings in them and put those out in the sun. That cooked their paintings dry out there in the desert in no time, I am sure.

I have panel boxes that will hold wet paintings and keep them out of trouble when I am traveling until they are dry. I should do a post on panel boxes, I don't believe I have.


Bob Carter said...

As you know, I am a chemist, so I can vouch that everything you say here is spot on. About drying in the sun, it shouldn't be a problem over one day if all the pigments are the highest permanence rating. Alizarin might be a problem, but everyone should be using a permanent substitute. (My favorite, Rembrandt's permanent madder deep, is one that is actually not quinacridone, but rather pyrrole rubine.) As the black iron box technique suggests, it's not so much the sun that quickens the drying as it is the heat. In general, most chemical reactions approximately double their rate for every ten degreee Celcius increase(18 deg F).

Judy P. said...

Stapleton- you have always good advice, and now you have official chemists chiming in to confirm its accuracy; Woody Allen would say now, "why can't life always be like this?"
My Ask Stape question (love the pearls and hair flip) is about varnishing- when to and how to. Some fine painters here in MN tell me to wait 3 days, then spray with Kamar Varnish - so nice and easy! They say the old advice to wait 6 months, then brush on varnish, is useless; you're in trouble if you still have your painting after 6 months. How say you?

Jeremy Elder said...

I have heard of people building heat boxes to dry paintings too.

Stapleton Kearns said...

Thanks for the backup. Whenever I write about anything that is chemistry I remember you are out there reading it. Glad to hear I got it right. I skipped chem class.

Stapleton Kearns said...

I will do post on that soon.

Stapleton Kearns said...

I tried to speed dry one in an oven once for a deadline on a show and it bubbled like pizza cheese and was ruined.

Deb said...

I once set my table on fire in chemistry class... so it is good to have knowledgeable folks giving us the real story here.. I obviously can't be trusted to play around with chemicals....

Bob Carter said...

Had you been a better chemist you would now be a major general. :-) And what a loss that would be!