[Ovalman]

Hello folks,

I'm new to this board and writing with a problem which has me completely frustrated. I turned to this board hoping someone can furnish an answer or point me in the right direction.

I'm a professional artist who makes oil paintings (and retired art professor). I have a private studio space (660 sq. ft.) in a large industrial building. The building (built in 1925) was converted into studio spaces 3 years ago and all ceilings of the building were sandblasted to remove lead paint from the cedar rafters and exposed plank sub-flooring.

I am set up to work against one of the long walls of the studio, more or less in the middle of the long, narrow space. I keep the space scrupulously clean and have installed an air filtration unit which is suspended from the ceiling. I also covered the central third of the ceiling (the area where I work) with plastic to prevent any debris from falling. I've done this because there is some residual sand and other pulverized debris from the sandblasting stuck between the exposed plank floorboards, although I've vacuumed much of it out.

My problem is that, as I paint on a canvas, my wet paint is attracting what apparently is this residual sand and grit. It appears on the painted surface and also on my palette, where I mix my colors. And it seems to come out of nowhere: I literally watch as particles of grit attach themselves to my painted surface and settle on my palette in minutes—hundreds of small particles, say, over a sq. ft. or two.

I am speculating that there is a static charge created when I'm mixing paint and applying it to my canvas that attracts these particles of grit. Or the wet paint itself possesses a static charge. What I don't understand is the great distance these grit particles seem to travel to attach themselves to my painted surface. My ceiling is 11' high, again, covered in plastic over the area where I work, and I generally keep my studio as spotless as I can. This grit doesn't appear on any other surfaces in my studio (such as my workbench, desk or floor), only where there is wet paint.

My question (if I'm on the right track) is: can there exist such a force of static electricity that it would wrest particles of grit out of the crevices of a ceiling (or wall) 15 or 20 feet away and draw them to my wet paint surface? If not, what is the cause? And what might I do to solve the problem? It seems this problem would occur if I were painting anything—a piece of furniture or a motorcycle.

I have also run a humidifier during the winter to perhaps lessen the static charge but it's made no difference.

Any ideas would be greatly appreciated. Thanks for reading; I've tried to furnish pertinent info. I am happy to provide any other info that might be helpful.

[Enthalpy]

Welcome, Ovalman!

I don't imagine any force attracting dust from a big distance. If there were a significant electrostatic potential between your paintings and the surrounding, you'd feel it when you touch the painting, zap, ouch.

More probably, the air carries dust that settles on the fresh paint when passing randomly in its vicinity. You could stick double-sided tape (for carpets) on an equivalent surface and observe that as much dust deposits on it.

You could install a strong light with some baffles to create a ray through the air, and from a direction not illuminated, observe how much dust floats in the air and how it moves. My bet is: no global movement towards the paintings, only local wind.

The amount of dust observed that way is always impressive and difficult to relate with the amount that deposits on any surface. But you could reproduce the setup in an other room where your paintings stay clean and get a qualitative comparison.

Means to avoid dust:

Cover the surfaces that emit dust. Paint, varnish, plaster...

Remove the dust from air with a fan and a filter.

Remove the dust from air with slowly rotating disks that plunge their lower part in water. Much dust in a big room may need many big disks. More silent and energy-saving than the fan and filter, easier to maintain. Available commercially against tobacco smoke in small rooms.

[Ovalman]

Thanks for your response, Enthalpy.

Your idea that "the air carries dust that settles on the fresh paint" was my first thought, which is why, after cleaning the space thoroughly, I installed an air filtration unit which presumably exchanges the air about 4x/hour in my volume of space. But it's made no difference. And the filter is remarkably clean which shows the air in my studio to be generally very clean.

I would not consider these particles to be "dust" (i.e., the kind of dust one sees in, say, a living room through a sunbeam which, agreed, is everywhere). The largest particles I'm getting on my painted surfaces are about the size of the grit of 80 to 100 grit sandpaper, or the size of table salt. I've looked at these particles through 5x magnification and they are clearly sand (along with some other residual debris such as pulverized paint from the sandblasting).

I can't imagine "sand" and other particles this size and weight lingering in the air. I don't see them. I have spotlights over my work area(s) and I can look into them in the way you suggested by creating a beam of light. There is no debris in the air. And most perplexing is that, if this grit were being carried by the air, I would think it would settle everywhere in my studio: on the floor, on my large work table, on my desk (on which I'm writing this). There is none of this grit anywhere else in my studio—it simply appears, seemingly by magic, on the surface of a painting as soon as I begin to apply the paint. This is why I've concluded that it must be 1), attracted and 2), traveling long distances, perhaps from other parts of the ceiling I've not covered with plastic—15' away or so.

Adding to the mystery is that often the particles appear first at the bottom of the painting—as if they're leaping onto the wet painting from the floor! I've tried spritzing the floor with water, again, to lessen any possible static charge caused by low humidity. This seems to have helped at times but not at others.

Now you see why I'm so frustrated! The grit does seemingly appear out of nowhere. The source of the grit must be the nooks and crevices of the ceiling and elsewhere that still have retained some of the sand from the sandblasting. But this suggests the grit is traveling long distances and doesn't stop along the way to alight on any other surface.

And you're right, the answer would seem to be to seal off the areas likely to be the source of the grit. (That's going to be a little tricky in this space.)

Thanks again for reading all this and for your thoughts, greatly appreciated. I could give a few more details but this is the gist. I actually thought that, once the weather became warmer and I could open my windows, the humidity would increase and lessen the static charge, if that were the problem. But it's been getting warmer out and has made no difference to my problem.

[Corribus]

Can you use a cross-ventilation?
Have you ruled out a problem with your paint?

[Ovalman]

Hi Corribus,

I've tried using a small fan to direct air away from my immediate work area and toward my air filtration unit. Hasn't helped. I will try a larger, box fan, thanks.

I talked to tech support at the manufacturer of the oil paint I use (it's a high-quality, professional brand). They are as stymied as I am; have never heard of anything like this before. Usually artists are trying to make their spaces less humid to speed up drying time. And honestly, I don't know what aspect of the paint would render it "attractive" to matter other than its wetness.

I've had studios in other industrial spaces before and have never had a problem like this.

[Corribus]

One other possibility - could it be originating from your clothing? Clothing could easily harbor dust, which is then agitated during the action of painting.  You could do an experiment by trying some painting in a neutral environment and see if you still observe the defect on your canvas. This way you could hone in on whether it is your ambient environment, something on your immediate person, or your materials.

[Borek]

Or try to pain naked (no joking).

[Corribus]

Maybe a plastic garbage bag with head and arm holes cut out?

[Ovalman]

Thanks again Corribus and Borek. The problem is that it's not dust; it's grit the size of table salt. I'm not carrying this around on my clothing. I've identified it as sand under 5x magnification and it must be the residual sand and debris from the sandblasting of my ceiling before I moved in (where else would it come from?). And it feels like table salt to the touch—granular.

I have "typical" dust in my workspace but it's very minor, just as you'd find in a house, office or other kind of workspace. This is a unique problem. And to top it off, my immediate neighbors are ceramists and have no issues with "grit" in their glazes or when they produce 2D work—even though their studio is full of clay dust!

It's crossed my mind this stuff might be evil spores sent from outer space to reproduce...

[Ovalman]

Although I do like your fashion suggestions.

[Enthalpy]

Grain that size falls quickly to the floor. Attracting it would be nearly magic. At most, insects deposit it selectively on the painting.

I believe less this dust is carried in air. Possibly the paint contains some fine solid (the metal oxide pigment?) that crystallizes out or agglomerates when the oil hardens.

An experiment: paint any surface, expose it to filtered air, observe. I'd have a cloth enclose the paint, a few cm above the surface. The cloth must let air through to harden the oil but be finer than the observed "sand",

And do the experiment in an other room too.

With a different paint as well - just absolutely banal recent oil paint from the Chinese grocer's at the street's hook.

[Corribus]

That's what I'm thinking Entropy. If the granules are really that big, they wouldn't be easily transported by background air currents. They'd have to fall directly from the ceiling. You'd also see them all over the place, not just on the paint. Could be problem with the paint, or possibly the drying rate.

Were it me, I'd take a canvas to a friend's house, paint something, see what happens.

[Ovalman]

Hey Enthalpy,

"Grain that size falls quickly to the floor. Attracting it would be nearly magic." —This is what's driving me crazy.

It's not the paint. I've been painting for 40 years in a variety of studio spaces. Oil paint has an extremely fine consistency which remains through drying. The only variable in this space is the fact that the ceiling had been sandblasted. There is no other source of this debris. Also, these particles appear on my paint palette which sits on a glass-topped tabouret next to my painting in progress. The debris (mostly sand) appears next to the paint I've been mixing, as if the act of mixing up wet paint has created a static charge.

What I mean is: I'll wipe my palette until it's absolutely clean (or use a fresh one), wipe the glass surface of my tabouret (portable cart) and begin mixing color. After several minutes, a dozen or so particles of sand will begin to appear along the bottom of my palette. It's as if they leaped from somewhere but couldn't quite make it into the wet paint. Also, I work with my paintings propped up on a cardboard box set against the wall. The particles will also "leap" onto the cardboard box: I'll run my hand over it and find it covered with particles.

The only thing that seems to have made a difference is when I've run a humidifier right next to my work area and spritzed the floor and nearby walls with water (I've not tried to humidify the entire space). My aim was to lessen the "static charge" due to the room's low humidity which I had theorized was causing all this. This has actually helped—which bolstered my theory—but not entirely. Maybe I'm just not being consistent with keeping the area humid enough. If higher humidity in the room does help, I'll know this soon enough as the weather warms and I can open windows.

So, originally I was hoping someone would confirm my idea that very low humidity had created a static-rich environment such that my wet paint, or even the process of my applying it, would serve as an attractive force to these particles. But you're saying that such attraction would be "nearly magic." I certainly agree but then I'm without an answer! Is there another kind of attraction?

Thanks again for indulging all these details. Am I allowed to post my website of work on this board?

[Ovalman]

Corribus,

"They'd have to fall directly from the ceiling. You'd also see them all over the place, not just on the paint."

They're not falling. They'd be everywhere, as you say.

[Ovalman]

And I want to stress my studio is extremely clean (other than normal dust). The desk I'm typing this on has no debris, nothing. My floor is clean, etc.