Introduction: Sculpting With Polymer Clay

About: When I was young I took all of my toys apart just to see inside. Eventually I learned how to put them back together.

Polymer clay is wonderful stuff. It's inexpensive, easy to find, and can be molded into anything you can dream of. A few years ago I started playing with the clay as a way to focus my creative energy away from video games. In this instructable I'll be sharing a few of the sculpting and finishing techniques that I've picked up while sculpting with oven-bake polymer clay.

The type of clay that I've always used is Super Sculpey, which can be found almost anywhere that has some kind of craft section. Joann Fabrics is where I've been getting mine lately.

Inspiration
Clay that you can bake in your oven has been around for years, but it seems like the popularity has ramped up recently what with the social medias and diy shop websites and all. Through those sources I found several artists that really inspire me; I see their work and can't help but be envious and mystified by their skill.

Monster Kookies - The Mad Scientist of Polymer Clay (www.monsterkookies.com)
Beastlies - Adorable Mini-Monsters (www.beastlies.com)
Beat Black - Polymer Clay in It's Most Visceral Form (www.etsy.com/shop/beatblack)

Step 1: Tools of the Trade

Although you don't absolutely need a set of sculpting tools, there are a few that are incredibly useful, especially for creating fine details. Over the years I've gotten several sets of tools but 90% if the time I only use four or five of my favorites.

Royal Sovereign Clay Shaper Sets
I love these little rubber tipped brushes. They are just flexible enough to work on a surface like a tiny finger. These guys are kinda expensive though (a set of four costs about $30,) but they are absolutely worth it.

Dentist Pick
You know the pointy ones that they poke around your mouth with? They also work great for sculpting and you can get them dirt cheap from American Science and Surplus.

Wax Carving Metal Tool Set
Similiar to the dentist pick, these usual come in a set of a dozen tools with all kinds of odd shaped tips

Loop Tools
As the name suggests, these tools are made from loops of bent wire ribbon. The edge of the wire cuts through clay and removes it from the sculpture and are useful for hacking out the subject's general shape. They can be used to create large grooves, or for shaving away small flakes of clay.

Kemper Circle Pattern Cutters
These small tubes behave like cookie cutters, but for clay. They are pressed down into a flat sheet of clay to cut a circle, which could be done with any metal tube, but these cutters have a clever button on top that lets you pop the newly made, clay disk out.

Pasta Machine
The classic style, hand crank pasta machines are perfect for pressing clay flat and for mixing colors. I've also seen people use these for making noodles, but you shouldn't do that after using one for clay.

Improvised Tools
I consider drinking straws and sewing needles essential parts of my tool set. Old toothbrushes can be carved into chisels and wire can be hammered flat to make knives and scoops. Plastic toothpicks also work very well as the ultimate multitasker.

A long while ago I was working on a  zombie mutant thing who had exposed portions of muscle, I ended up gluing a half dozen sewing pins to a piece of wood to create a small rake. I then scraped the rake over the surface of the clay and smoothed it out with alcohol. The striation texture made the muscles look absolutely spot on, take my word for it (sorry, no pictures.)

Step 2: Firming the Clay

Personally, I think that Sculpey is way too soft to work with straight out of the package. Fortunately there is a simple trick to firm the clay up making it better suited for holding details. By soaking oil out of the clay with a few sheets of plain paper the 'squishy-ness' of the clay can be changed from bubblegum to beeswax.

  1. Flatten a ball of clay out onto a sheet of printer paper, I used a chunk of dowel to speed it up.
  2. Place another sheet of paper over the clay and press it down flat to get as much contact with the clay as possible. Here I've rolled a chunk of wooden dowel over the paper to ensure max flatness.
  3. Wait for a day and the clay will be much firmer and ready to use. The longer you leave the clay between the paper the more oil that will be soaked up, and the firmer the clay will be.
  4. If you want even firmer clay, apply a clean sheet of paper and wait another day for even more oil to be soaked away.

Step 3: Starting With Basic Shapes

Have you ever seen the early stages of a cartoon being drawn, how the artist will begin by creating vague shapes to block out the body of the character? They go in afterwards and add the details to the shapes and eventually a noticeable character emerges from the bubbles. The same process works equally well for sculpting, but instead of planning with lines you sketch with 3d shapes.

For example, the cheeseburger for this Pusheen the Cat sculpture was made almost entirely by rolling up balls of clay and smashing them flat with the palm of my hand. Instead of meticulously sculpting every single dimple on the meat of the cheeseburger, it was far easier to roll out a small snake of clay, cut it into sections, and roll the sections into balls that could be squished up against the hamburger. After the hamburger was made solid via baking, the bumps were smoothed out by smearing clay into the voids.

To create the lettuce and the cheese, two more balls of clay were flattened out on the table. Then I used a knife to cut out the square, cheese shape and the curvy lettuce. The pieces were then lifted off of the paper and draped over the hamburger like they were the real thing.

As you've probably guessed by now, the tomatoes were also made from squished clay spheres.

The top bun is more of a half squished ball, I rolled my finger along the top of the bun to smooth the surface and get the curve right.  This particular cheeseburger needs to have a bite taken out of, something that would be very difficult to sculpt by hand. Instead of even trying to do that, I went to the kitchen drawer, found a drinking straw and used it to cut the bite marks out of the bun.

Step 4: Smoothing the Clay Surface

One of the most frustrating things about working with clay is trying to get a smooth surface. We've already firmed the clay, and that will make it much easier to smooth the clay with your fingers. However, if you want to a very smooth surface that is completely free from bumps, marks and fingerprints, there is another simple trick. Alcohol melts Sculpey.

We can take advantage of this by dipping a paintbrush in rubbing alcohol and then gently brushing the sculpture until the alcohol dries. Minor imperfections (fingerprints) in the clay will be dissolved and essentially buffed out of the surface of the clay. The cool part is that the stronger the alcohol solution is, the "mushier" the surface of the clay will become. This means that you can dilute the alcohol with water to make a less aggressive solution, effectively making a 'finer grain' of liquid sandpaper.

  1. Start with 91% Isopropyl rubbing alcohol. Brush it over the sculpture to remove large scratches, fingerprints, and tool marks.
  2. Mix water with the alcohol until you have about a 1:1 ratio. Continue brushing the sculpture with this new mix until the surface is as smooth as you can get it.
  3. Use water alone to brush the surface. With much brushing you will be able to get an almost reflective polish

Not smooth enough for you? Well, after you bake sculpey you can take sandpaper and polishers to it just like anything else.
Begin sanding with 300-400 grit sandpaper and go over the entire surface of the clay
Continue sanding with paper of gradually increasing grit density, all the way up to 1600
With dry sanding complete, start  the process again with the 300-400 grit, but this time soak the paper in water first
Use polishing compound and a rotary buffer (I personally like the Dremel polishing kit) to finish off the surface. You will be able to get a glass smooth surface with this method.

Step 5: Baking and Sculpting in Sections

If you have ever attempted to sculpt something from clay, I'm sure you've experienced the pain of accidentally smashing one part of the sculpture while working on a different section. To spare my sanity, I like to bake the sculpture in sections and thus preserve completed work and give myself something to hold onto. Un-baked sculpey will stick to baked most of the time and when it doesn't you can use super glue to make it stick.

Here I've finished work on the cheeseburger so I baked it for about 45 minutes at 150 degrees before adding the body of the cat.
There are a lot of variables that can affect the outcome of your clay baking, and every source will give you a different opinion. Sculpey will crack if backed too quickly, or at too high of temp for too long, or if you look at it funny; it can be fickle stuff. My personal baking philosophy is to set my oven low and bake for a long time. It takes some patience and planning, but I've yet to have a crack result from baking this way. 

The technique used for sculpting of the cat itself goes back to the cartoon drawing concept by starting with a bean shape. Legs were pinched out of the corners of the bean, and a ball was smooshed on and pinched to make a head and ears. To attach the head to the body seamlessly, I first smoothed it out as much as I could with my finger and followed that with some alcohol brushing.

Ears were then pinched out of the head. In the next step you will also see holes in the face of the cat for the whiskers, these were made with the end of a paper clip. A paper clip was also used to make the tail by rolling clay round it and shoving one end into the body.

Step 6: Basic Painting

Normally I use the cheapest acrylic paint I can find, usually small plastic bottles of it from the craft store, but for this project I ended up using some higher-end paint that is slightly more expsensive. I must admit that I did prefer the nice stuff, it was more concentrated and I was able to mix the colors with less mess than usual.  Still, no mater which type you use the painting process is essentially the same:
  1. Paint a base coat with black or white acrylic paint diluted with water, it may take several coats. The base coat serves several purposes here: it covers up any discolorations in the clay and it also gives a backdrop to additional layers of colored paint so that they stand out.
  2. Mix the colored paint with water until you get it to an ink like state and begin painting. Plan your mistakes and paint the colors in an order that will make them easy to fix. Here I started with the red tomatoes because I knew that there was no way I would be able to do so without getting red paint on the lettuce in cheese. By painting the tomatoes first I am free to make those mistakes with the red and then cover them up later when I paint the cheese and lettuce.
  3. Depending on how concentrated your paint is, you may need to paint several coats of a single color to get it to the proper saturation.
  4. Some times it is easier to make fine lines, such as the mouth of Pusheen, with a marker instead of with a paint brush.
  5. When you have finished painting your sculpture cap it off with a few protective coats of clear paint. Matte clear spray paint is a good choice, but you can also use brush on acrylic.
I used paperclips for the whiskers of Pusheen. The were cut to length and bent slightly before being painted black. The whiskers were then glued into the cat's face before clear coating.

A Word on Arylic Paint
Up until recently I solely used the cheap paint that can be bought at most craft stores for $1.95 a bottle. I have dozens of these paints in about every color they make stashed away in my craft chest, which I thought was a handy resource. The thing is, when you buy a bottle of paint every time you need a different shade of blue, you end up with a lot of bottles that don't get used all that often. After two or three years the paint in the bottles will begin to dry up and you will be left with a drawer full of colorful bricks that are useless for painting sculptures.

After tiring of dealing with my own drawer of bricks, I decided to stick to buying only the primary colors (red, blue, and yellow) and black /white paint. When I need a different color I mix those 5 basic colors to produce it. I then keep these new colors in small plastic bottles or in an ice cube tray with a plastic wrap cover. This does require some forethought if you are going to need a large amount of one color though, be sure to plan ahead and mix enough the first time! Mixing a new batch of matching color is very difficult (for me at least), and the challenge is compounded by the fact that the paint is a slightly different color when it is wet as opposed to dry.

Step 7: Bonus Tips

Creating Textures
Remember how we used rubbing alcohol and a paintbrush to smooth out the surface of the clay. Well this technique can also be used to make simple marks in the clay look like a convincing texture. In the picture of the blue dragon you can see how marks were made in the clay with the pinched end of a drinking straw, as well as tiny balls of clay and other obvious tool marks. When these marks are dissolved a bit and brushed they start to meld together, making the skin look scaly.

Texture can be a powerful tool in your sculpting arsenal, especially when paired with paint. The grooves, ridges, and bumps give washes places to hide in and gives dry brushing high points to hit.

Texture Stamps
Much in the same way that ink stamps make imprints on paper, clay stamps can be made to easily make texture in sculpey. In the accompanying images you will see two yellow texture stamps that were made from clay and then baked, along with examples of the texture they make.

Stamps make filling out large patches of texture a snap, and by overlapping the stamps you can get a nice random look.

Using Tin Foil as a filler
Making a sculpture that is thicker than a couple of inches can be problematic. Not only is it a waste of clay, but thicker pieces are slightly more likely to crack during baking. Using crunched up tinfoil as a filler solves both of the problems, just make sure that your adding at least 3/8 around it to give yourself room to sculpt. I've tried using less but every time I do I end up hitting the foil and have to work around it.

Step 8: Epilogue

I began using polymer clay somewhere around 2007 and have spent many of hours hunched over tiny blobs of the stuff. Although the clay was good to me during that time I've recently moved away from it in preference of wax. In my experience poly clays are not suitable for holding fine details and more than once I've finished work on part of a sculpt only to find a massive fingerprint in the back. I've also broken most of my sculptures in some small way long after they were finished, which feels like backing your car over your own pet.

Sculpting wax, or more specifically, casteline, is used by professionals in the toy industry to create artwork that will later be replicated from a sturdier material, such as plastic. What makes wax so wonderful to sculpt with is that, with a bit of heat, it can go from solid to liquid and back again in less that a minute. It can be warmed up and worked like clay, or be kept cool and carved with sharp tools. It's strong and resists warping, it's easy to "weld" parts together by melting the joint, and you can touch it without out destroying details! It really is great stuff, expect an Instructable from me on the topic soon. If you simply can't wait, then search around and you will find plenty of instructions for working with wax, like this one.

Thanks for reading my Instructable, please do not hesitate to ask any questions or leave any suggestions! Remember that there is never just one way to do something and that practice does make a difference. Sculpting is a lot of fun and it is relative cheap as far as hobbies go, if you've never played with a chunk of clay your really should give it a go at least once, good luck.