Chalkboard Rejuvenation

February 20, 2007 7:23 AM

What's the deal with chalkboard schmutz?

I've been doing whiteboard animations all (3 day) weekend. It's really awesome, but a shiny, white surface pointed directly at the camera makes controlling the light levels a little difficult. Plus dry erase markers are a hassle (though at work we have a few more reliable liquid version, but it also ran out of ink after only a few months so maybe that's not the answer).

SO, with all those problems I'm thinking I should switch to chalkboard and colored chalk. I even have some small chalkboards that could be perfect. The problem is, they don't take chalk very well anymore. Why is that? (There's no specific, identifiable problem with the boards like crayon--it's like they've oxidized or something and have a thin coating preventing chalk from adhering.) More importantly, is there any way to rejuvenate a chalkboard that has this problem?

posted by DU to Media & Arts (12 answers total)

Best answer: When I was teaching school, I was told not to wash the chalkboard often, because it was actually the fine film of chalk dust that helped new chalk to adhere.

That could be complete BS, though. I don't know.

I do know that when I was a kid, there were 'real' chalkboards -- large pieces of dark gray slate. That green stuff seems to be a paint or enamel coating on some other subsurface, and I don't think they're as good.

Your question makes me remember the creamy satisfaction of making a nice thick chalk line on a real slate chalkboard. I too would like to know why most modern chalkboards don't give that same feel.
posted by Miko at 7:30 AM on February 20, 2007

Best answer: is there any way to rejuvenate a chalkboard that has this problem?

Assuming you're not talking about slate chalkboards, what you want is chalkboard paint.
posted by Kirth Gerson at 7:37 AM on February 20, 2007

Response by poster: That chalk dust thing does sounds like BS. When they make a new chalkboard, do they have a machine that automatically rubs a bunch of stocks of chalk on it to "prime" it? Plus, we used to wash our board at school once a week and the assignments still went up just great, unfortunately.

Wearing through a coating, though--that's a promising line of inquiry. I probably don't want to shell out the simoleons for real slate (which is probably also fragile) but I could probably just repaint these boards and they'd be like new.
posted by DU at 7:37 AM on February 20, 2007

re: priming the chalkboard -- actually, yeah, kind of. When I got a chalkboard as a kid the instructions for washing it said that after you washed it you should rub the side of a piece of chalk against it to cover the board, first horizontally, then vertically. After that you'd erase the board and resume normal use. Sometimes I'd do it, sometimes not, but it did seem to help.
posted by katemonster at 8:18 AM on February 20, 2007

I'm sure I remember our teacher at school either "priming" a new blackboard herself or getting us to do it, in a manner much like that described by katemonster.
posted by EndsOfInvention at 8:37 AM on February 20, 2007

Part of the problem is that far too often the chalk is quite frankly cheap crap - dust with a substandard binder in it, so that it acts greasy (and won't erase easily) or is far too hard to write with.

I've been teaching using chalk and board for years, on old-school slate boards left over in ancient buildings to the new metal and enamel boards they manufacture now. I used to wash the board with sponge and water before or after class, and so long as the board was dry there was no problem writing on it. The problem is cheap chalk, 99% of the time.

Sad to say, Crayola is really bad these days. It's basically small sticks of sidewalk chalk, mass-produced in China. It isn't made for chalkboard use, or at least it isn't very good for it. The best stuff I've found so far is Prang Hygieia, made in France. Writes smoothly, erases almost completely, very low dust, and the colors are quite bright and easy to see.
posted by caution live frogs at 9:31 AM on February 20, 2007

You could try using Chalk Ink, which is the painterly chalk they use in produce departments signs or coffee shops for the menus on chalkboard. It might be a nice medium (pun intended) between white board markers and traditional chalk.
posted by cocoagirl at 9:50 AM on February 20, 2007

Chalkboard priming.
posted by Floydd at 9:59 AM on February 20, 2007

katemonster: "re: priming the chalkboard -- actually, yeah, kind of. When I got a chalkboard as a kid the instructions for washing it said that after you washed it you should rub the side of a piece of chalk against it to cover the board, first horizontally, then vertically. After that you'd erase the board and resume normal use. Sometimes I'd do it, sometimes not, but it did seem to help."

In my experience, this is true of cheaper chalkboards-- like the little ones, which appear to be wood with a layer of chalkboard paint-- but less true of schoolroom chalkboards. This says that those schoolroom chalkboards are now made of a porcelain layer over steel. That makes sense to me-- I've always noticed a big difference between little chalkboards and the full-size schoolroom version.
posted by koeselitz at 10:10 AM on February 20, 2007

Best answer: Porcelain-on-steel is how they may dry-erase boards.

You may want to look for a beige/off-white dry-erase board. These are made to reduce glare, so should be easier to photograph.
posted by Goofyy at 10:35 AM on February 20, 2007

Response by poster: Skeptical but open-minded, I just tried rubbing a piece of chalk all over the board. It works great now. WTF, but OK.
posted by DU at 6:52 PM on February 20, 2007

Wash a chalkboard using a damp cloth with water only, not household-cleaning-stuff or soap. Cleaners will leave a residue that will prevent chalk from adhering.
posted by Pallas Athena at 10:14 AM on February 21, 2007