This past weekend I worked on a new concrete project. I experimented with creating my first piece of relief art. A “relief” refers to a sculptural technique that gives the impression that the material has been raised above the background plane.
The idea for this project originated from an article I read a while back about an artist who created relief art in plaster. She embedded objects into a flat section of clay to create an impression, then removed the object and poured plaster over the clay to create the relief. There weren’t any specific instructions on her process, but the article sparked some inspiration in my noodle and the wheels started turning.
Now, the last time a played with clay I was probably 12 years old, so I really had to start from the beginning to figure out what the heck I was doing. But with a little research, and a little trial and error, I was able to put together my own little process.
To start you’ll need is some oil-based clay. The first thing I learned when reading about working with clay is that you don’t want to use the kind of clay that you use to make pottery, i.e. water-based clay. Water-based clay will dry out and become brittle when exposed to air. Oil-based clay will not.
So I ordered some oil-based clay on Amazon, specifically, I purchased two 2-lb bricks of Roma Plastilina Soft Modeling Clay.
You can purchase oil-based clay in soft, medium, or firm. I found the “soft” clay to be pretty firm, so I recommend getting the “soft” clay.
You’ll need to turn your clay blocks into a flattened sheet of clay. You can purchase specific tools for cutting and working with clay, but I don’t have any of those so I had to wing it to flatten out my bricks.
The tool one would normally use to cut a clay brick consists of a wire attached to two small handles and to cut the clay you would pull the wire through the clay. I didn’t have one of those and cutting with a knife was quite a challenge. But in my research, I found that I could melt the clay. Yay! I figured melting would be easy enough, so I lined a baking pan with some parchment paper (my no-stick solution), put my two bricks on the parchment and stuck the pan in the oven at 250 degrees.
It took about an hour for the clay to get soft enough to cut through with a knife. So at that point I sliced it up and then stuck the whole thing back into the oven.
My goal was to get the clay melted enough so that it would self level.
It took about three hours in the oven for the clay to get to this consistency…
At this point I could have stuck it back into the oven to melt a bit more and self level, but it was getting kind of late and I wanted to go to sleep. So I turned off the oven and let the clay cool over night.
In the morning, the clay was cooled and solid again, but pliable enough to work with. Since I didn’t wait for the clay to heat enough to self level, I needed to hand work it to get the smooth surface I needed. And since I don’t have any clay-working tools, I took a spatula and simply ran it over the top of the clay repeatedly for about 20 minutes to get a smooth surface.
The next step was to select an item to create an impression in my clay. Here’s where the trial and error came in and a few lessons were learned. For my first try, I picked some flowers and viney plants from my mom’s garden and pressed them into the clay and the result was a big fail. First, the impressions left by these items were very shallow which means that the final raised relief would also be very shallow and I wanted something more pronounced. I also found that once I pressed the plants into the clay, it was really hard to get them out because the plants would stick to the clay and then break off when I tried to lift them up. So I had to use a tweezer to try to get all the plant material removed and that left all these tweezer marks in the clay. I tried to smooth over the tweezer marks, but I ended up making more of a mess. So I decided to do something completely different. I would still like to make a relief with plant impressions, but I’m going to look for some fake plastic plants that will leave a deeper impression and won’t fall apart.
Since my plant idea didn’t work, I found something a bit more substantial and I decided to go with this…
It’s a super cute Betsey Johnson necklace, but I never wear it.
Using my spatula, I smoothed my clay surface again and then pressed the necklace, face down, into the clay.
When I pulled the necklace up, some of the clay did pull up with it. So I smoothed out those areas again and moistened the clay with some mineral spirits (something else I picked up from my research) and pressed the necklace back into the clay.
The mineral spirits made a big difference in allowing the clay to release the object without sticking to it. Here’s what the final impression looked like…
The next think I did was create a frame for the area where I wanted to pour my concrete. To do this, I cut some 2″ thick pieces of poster board.
Taped the edges together…
And pressed the poster board frame into the clay.
Time to pour my concrete.
I used Rapid Set® Cement All®. It’s perfect for casting and it dries in about one hour so no waiting 48 hours to a final result. Yay! Plus, it’s stronger than traditional Portland Cement. What’s not to love?
Mix your Rapid Set® Cement All® according to instructions (four parts Cement All to one part water).
And pour it into your frame. Once you pour your concrete, give the entire pan a few good shakes to make sure the Cement All fills in all the nooks, crannies and corners.
Next, smooth out the surface of your concrete. My trowel is too big to use within this small frame, so I just used my metal spatula to smooth the surface.
Then I inserted a picture hanger into the smoothed concrete.
Bend the nails of the picture hanger before inserting them. That will ensure that they will not be able to be pulled out once the Cement All® is dry.
After an hour just pull off the poster board and flip your baking pan. Your concrete relief will pop right out.
A bit of the clay did stick to my relief.
If your clay sticks, just peel it off. Some of the clay was stuck in the deeper parts of the chain impression, so I used some dishwashing soap and a stiff bristle brush to scrub it off.
Here’s the relief compared to the original necklace…
Pretty cool, huh?
I did want the relief to pop a little more from the surface. So I used some craft paint with a small paint brush to highlight the relief and make it stand out a bit more…
I also painted the edges of the concrete block, which I’m also totally diggin’….
Here’s some close-ups…
There ya go, Betsey Johnson inspired concrete relief art using Rapid Set® Cement All®.
As I mentioned earlier, I’m going to try this technique again to create the relief of a flower. I’d like to make a great big sunflower. One of the nice things about working with oil-based clay is that you can use it over and over again. There were a few tiny bits of concrete particles that remained in the clay, so you’d want to remove those before starting a new project. The best way to remove any small particles is to re-melt your clay and pour the melted clay through a fine metal strainer. You can easily make your own strainer by using a piece of screen material.
Anyway, I’ll let ya know how my next relief goes.
Super cute wall art! Thanks so much for sharing this project, my mind is spinning with ideas!
Awesome Sierra! I’d love to hear what you end up making!!!!
THis is awesome ideas thanks so much i’m going to try it i mist go l[k for that cement now…
Thanks so much Judy! There are so many possibilities of things to create using this technique. Good luck with your project!