I love this technique! I recently used it on a big old 16" vinyl record that I did for a solo art show (The Big Mandala Show) which I have up this month at Seven Planet in downtown Portland.
SGRAFITTOSgrafitto is a technique where you scratch through one layer of paint to produce a drawing in the layer of paint beneath it. I learned about this when teaching elementary school art classes (using crayons) and have always been intrigued by the concept. I even showed my son how to do it on his wall!
Ha ha.So here' s how I did the record.
First (after priming the record) I used a pencil to just basically scribble all over it and make a lot of overlapping, criss-crossing lines, just dividing it up into as many shapes as possible. You don't have to really think about this. The idea is NOT to make a pretty design, because no one is going to see this. The idea is just to get lots of different colors on there. You could just splotch it on.
Mine turned out kind of cool. It was sad to paint over it, and I almost just left it like that! A black outline would have made it really rad. But, I was determined to sgraffito it, so I did. 
Now, if I had some black latex house paint on hand, that would have been ideal. It doesn't dry so fast so it would have given me more time to do a good job. But, I didn't have any, and I wanted to use materials on hand instead of going out and buying new stuff. So I used black acrylic paint which I mixed with LOTS of stuff to try to slow down the drying, including Slo-Dri Blending Gel and Glazing Liquid. Both of these products help extend the drying time, and this is really important. I found that it dried really quickly anyway, so it was a bit of a challenge. And you know what? I loved that challenge. It was fun and exciting to be forced to work quickly!
Luckily, I planned to work in small sections. If I'd painted the whole thing black all at once, it would have been a nightmare. Instead, I just started in the center and slapped on a small circle of blackness.
I've designed many a mandala in my life, and only about once or twice have I ever actually had any sort of design in mind before starting. I had no plan for this one either, so I just had to get started and see what would happen. I used the eraser end of a pencil to scratch through the wet black paint, drawing a simple flower with five petals.
Well, I wasn't very happy with the pencil eraser, so I switched to an un-bent paperclip. This worked very nicely and gave me good crisp lines that weren't too thick or too thin.
While I was working, I realized that I didn't like my original flower design in the center, so I painted right over it with more black paint and started over. 
Once I'd made the nucleus of the mandala, I then added another layer of paint around the circumference of the first one, and continued scratching into that paint and turning the record to continue the mandala pattern.
I just kept adding on to it until I reached the outer edge. As I got closer to finishing, the paint became more difficult to work with. It was drying so quickly that I had to draw my designs insanely fast. This definitely made the finished product different from my usual intense precision and perfectionism!
But, I did have three different people tell me it was their favorite piece at the show. That made me happy.Here's what it looked like when it was done and dry:
I'll post a few more pictures of the Big Mandalas and the Big Mandala Show soon!
