Cold Porcelain, or Porcelana Fria, is a modelling clay that is versatile, durable and can be made at home with common household ingredients. Not to be confused with cold cast porcelain, which is an entirely different thing, cold porcelain gets it's name from two of it's properties: that it hardens at room temperature, eliminating the need for a kiln or oven, and that it can be made to have a porcelain like quality when finished.
Recipes for cold porcelain vary widely but it basically has 4 main ingredients: white glue, corn starch, oil, and some type of preservative. I have chosen one recipe that I have found works well for this Instructable.
Step 1: The Recipe
This version is made with tacky glue or a similar strong glue such as white carpenter's glue. It is then cooked over very low heat.
What You Need:
1 1/4 cups Aleen's Tacky Glue
1 1/4 cups corn starch
2 Tbs baby oil (or vegetable oil)
2 Tbs white vinegar
Small amount of Nivea cream (about 1-2 Tbs)
1-2 Tbs white acrylic or tempera paint or white food colouring, such as Wilton White White (optional)*
Large mixing bowl
Wooden spoon and/or silicone spatula
Non-stick frying pan
Plastic wrap and resealable bag or air tight container
Optional: silicone coated parchment paper
*The white paint/food colouring is added to make the cold porcelain opaque. Without it, it will be translucent, and slightly yellow in appearance.
Step 2: How to Make It
1) Measure all of your ingredients into the mixing bowl and mix well.
2) Transfer the mixture to a non-stick frying pan and place on stove over VERY LOW heat, as low as you can possibly make it.
3) Cook, stirring constantly and scraping the bottom and sides of the pan, until the paste thickens and begins to form into a ball.
Tip: Periodically remove the pan from the heat and set it on a cold burner as you stir it to keep it from over heating. This is especially important if you are using a cheap, thin pan from the dollar store like I am here. (A heavy cast iron pan is a better choice, if you have one.)
Once it is done cooking, it has to be kneaded while it is still hot. This is where you use the Nivea cream.
Spread a small amount of the cream on your countertop, or a piece of parchment as I have done here, and knead until you have a nice smooth, flexible dough. Your mixture should not be too sticky at this point, but if you find it sticking, just rub a little more cream onto your hands.
When finished kneading, it should be very stretchy and pliable and not too sticky. Form it into a ball and wrap it in plastic, then put it in a plastic bag or air tight container and let it rest for 24-48 hours.
Step 3: 24 Hours Later ( More or Less)
The next day, unwrap your cold porcelain and have a look at it.
If it was still very warm when you wrapped it up, you may have some condensation. I have never had this happen, but I have read about it. If so, you will need to pat it dry and replace the wrapping.
As you can see in the first picture, mine was a little sticky. Some people like to grease the plastic wrap with a little hand cream to prevent sticking. I don't worry about it unless it is really sticky.
Now you want to wrap it with a new piece of plastic, being sure to pull it nice and tight. Watch for air bubbles, like the one in the second picture, and try to eliminate them if possible. Cold porcelain dries very quickly when exposed to air, so you need to protect it as much as possible. I like to wrap it in a double layer and then put it in back in the bag.
Store it at room temperature, in a dry, cool spot if possible, but not in the fridge. I have read that it can be frozen, but I have never tried that. (I did try storing it in the fridge once, following advice from a tutorial I read somewhere, and trust me, it is not a good idea. It basically went bad over night.)
It is now ready to be used, but it may benefit from a little more rest. It should keep, if wrapped well, for at least a month. I have kept it for six months, after throwing it in a box in the basement and forgetting about it, and it was still in perfect condition.
Step 4: Adding Colour
Cold porcelain can be tinted very easily by kneading in a small amount of paint or food colouring. The balls on the left side in the picture were tinted with liquid food colouring, the ones on the right with acrylic craft paint. Each of these balls weighs between 1 and 1.5 ounces and I used about 4-5 drops of food colouring and 2-3 drops of paint.
The next picture shows some beads I made after they had dried next to the original colour. You can see that the colours darken considerably (they were actually even darker than they look in this picture) This is something you need to keep in mind when adding colour. Be sure not to add to much and keep track of how much you added in case you need to make more of one particular colour. Coloured cold porcelain will not keep as long, so you only want to colour as much as you need.
Paint can also be applied to the surface after the cold porcelain has dried, as I did with the blue beads here. Be sure to cover the surface completely, even inside the hole when doing beads like in this case. It is important that the cold porcelain be sealed completely to stop moisture from getting in.
I opted to leave out the white colouring when making this batch, but I added some to a small piece here to demonstrate the difference. The star in the middle of the picture has the Wilton White White in it, the other two do not. You can see that the ones without it have a slightly yellowed appearance when dry and are much more translucent when a light is shone through them.
Step 5: How to Work With It
I just made a few simple beads for demonstration purposes. They are kind of misshapen and and irregularly sized, but I wasn't really taking my time with them.
When working with cold porcelain, take out only a small amount at a time and keep the rest tightly wrapped. As mentioned earlier, it will dry very quickly when exposed to the air.
To make beads, form the balls (or whatever shape you want them to be) and then poke a hole through the center with something sharp and pointy. I used bamboo skewers, which are not ideal as they make very large holes and the clay tends to stick to them, but they worked well enough in this case.
Work the skewers gently through the beads, twisting a little as you go and trying not to squish them too much. When the skewer comes through the other side, it will leave a little ragged, raised area around the hole. This can be carefully smoothed out with your fingers, and can also be removed later.
In order to keep their round shape, the beads will have to be hung somewhere so that they are not touching anything. I used a plastic basket that was the right width to hold my skewers.
To make multicoloured beads, simply take a small portion of each of the colours and work them together. Blend them as much or as little as you like. (I think the ones I blended more look the best.)
While the beads are drying, it is still possible to adjust their shape by very carefully applying a little pressure to the areas you want to change. Just be careful to do this only while the cold porcelain is still soft enough not to crack. If you see any signs of cracking, stop.
Drying time will vary depending on the thickness of the beads and the environmental conditions, but allow at least 24 hours. These beads took about 48 hours, in humid weather.
Cold porcelain will shrink as it dries. How much it shrinks will vary depending on how you make it and what ingredients you use. Basically, the wetter it is, the more it will shrink, so uncooked versions and those made with added water or a watery glue will shrink more. Because of this shrinkage, the holes in your beads will tighten up as they dry, so you need to periodically twist the beads around on the skewers to keep them from becoming permanently stuck.
Step 6: Making Corrections
Even when cold porcelain is completely dried and hardened, it is still possible to make corrections and repairs if necessary, before the piece is finished.
Small cracks will often appear in cold porcelain as it dries. If you started with a good mixture made with quality ingredients and didn't let it dry out too much while you worked with it, there shouldn't be too many.
If you do get cracks, one of the best ways to repair them is with plain water. Apply a very small amount of water with your finger or a paint brush and rub it in until the crack is smoothed out.
Rough spots can be easily sanded down with some fine sand paper or an emery board. It can then be further smoothed out with water, which will get rid of any scratches left by the sand paper. Once it dries again, it will look good as new.
Cold porcelain can also be carved after it has dried, so for extra rough spots, a sharp knife can be used to pare them down, then they can be sanded and smoothed in the same way. It is tough stuff and it takes a fair amount of pressure to get the knife to go through it, so be cautious and keep the blade pointed away from you as much as possible.
Step 7: Finishing
One of the downsides of cold porcelain is that it is not waterproof. As you have seen, even when completely dry, it will still dissolve when it gets wet. This is great for smoothing out scratches and cracks, but not so great when storing or using the final product.
So this step is extremely important. Your cold porcelain creations must be sealed as completely and thoroughly as possible with some kind of protective coating. There are many options for doing this. I have seen tutorials using everything from Min Wax to nail polish. In the past I have used both Mod Podge and puzzle glue with good results. This time I used an acrylic medium/varnish because that is what I had handy. I applied 4-5 coats of varnish to each bead. I am not entirely happy with the results using this particular varnish. It left the surface a little bit tacky, but the weather has been very humid lately which might be interfering with curing process.
As with the paint, it is important to make sure every part of the bead is coated well, including the inside. You want to leave nothing exposed if possible. The painted beads should also be given a good coating of varnish to prevent the paint from peeling or chipping and provide an extra moisture barrier.
Step 8: Enjoy!
If you loved playing with plasticine and play dough when you were a kid, then you will love working with cold porcelain. It's play dough for grown ups, or perhaps for the little artist in your family who is ready to move beyond play dough to something with more versatility for creating their masterpieces. With similar properties to polymer clay, but at a fraction of the cost, it makes a great medium to practice with to hone your sculpting and modelling skills.
But it is not just for play. It is also used by professional artists to create collectable art dolls and figurines or everlasting bouquets of flowers for special occasions. Check out these websites to see some of the possibilities:
This site is all in Spanish, but even if you don't understand Spanish, you can follow along with artist Marisol Ramero as she shows how to create cute figurines, step by step, in her video tutorials.
Sangeeta Shah's delicate everlasting blooms show just how beautiful and detailed cold porcelain can be.
Photos 1&2: My beads coloured with food colouring, a quick key chain and idea for a simple necklace.
Photo 3: My painted beads, after I added a few more layers and a marbling effect. This could be a necklace or bracelet when finished.
Photo 4: Fall leaves and an acorn, the fridge magnets from my first Instructable, some small animal charms, and a barrette, ring and brooch. (There was a yellow brooch that matched the ring and barrette, but I don't know where it is now.)
Photo 5: Pumpkin earrings and brooch and a candy corn brooch I made for Thanksgiving/Halloween.
Step 9: Cold Porcelain FAQ- Question #1: But How Strong Is It?
There are a lot of questions about cold porcelain, and I decided to do a little experiment to answer this one.
I had some funky little flat beads that turned out just a little too funky, so I used them as the test subjects.
I took my little step ladder out to the patio and set it up. Then I climbed to the top, held the beads above my head, and let go. When standing on the top step, arm raised above my head, this makes a drop of about 10 feet.
One thing I forgot to mention before: Cold porcelain bounces. So I had to hunt a little for my beads after dropping them. I finally found them underneath some of the overgrown plants at the edge of the patio- in perfect condition, without a mark on them.
So I did it again. After the second drop, I did find a very tiny little mark on the edge of the red one, but otherwise they were still in perfect condition.
I continued the experiment with some of my first CP creations from a little over a year ago.
First up: Ugly Flower #1
This peach coloured flower was made using a bad batch of of CP that turned out really weak and cracked all over when it dried. I was certain it would break.
I was wrong. On the first drop, it bounced and rolled back under the step ladder, stopping next to a bag of garbage waiting to be put out. And it was fine.
On the second drop, it landed right on the point of one of the leaves. Not so much as a chip.
Next Up: Ugly Flower #2
This was my first attempt at making a rose. It didn't turn out too bad I guess, except for the shimmer powder I put on it that clashed horribly with the colour of the petals.
Since the petals on this were very thin, and it was not put together very well or finished properly, you would think it would break. But once again, not a mark on it, even after two drops.
Last Up: The Easter Egg
This was made with the same bad batch of CP as Ugly Flower #1. Because it was so hard to work with, I rolled it out and just cut out some basic shapes, which I planned to paint later but never finished.
Once again, I climbed the ladder, held it high, and let go. And once again, when I climbed down and retrieved it, I found not a scratch on it. The worst it suffered was a bit of dirt along one edge after the second drop, when it rolled across the patio stones.
In the last photo, you can see that I finally did manage to chip one little piece off of Ugly Flower #2, when my husband came outside to see what his crazy wife was up to and I dropped it a third time to show him (confirming his suspicion regarding my mental health).
So, in conclusion, the answer to the question is: It's really strong.