Saturday, July 21, 2012
Making your PaperCasting
-planned your design (for your first try it could be something very small and simple)
-conditioned and rolled your clay (if your design is not small, there's also a post on joining strips of clay)
-transferred the design onto the clay
-cut, backed, and baked your mold
(if not, click on the links and go for it!)
Hooray! you are ready to make your test casting. There's a lot of detail here for those who really want a crisp, top-quality casting - you can just plop in some pulp and sponge the water out and see how it turns out if you aren't picky or want a rough look - but you won't be able to tell what defects you might have in the mold.
First you make some pulp. You will need a blender, a strainer, plastic tubs/bowls, cotton linter or paper, methycellulose optional. For filling your mold you will need flat toothpicks, clean flat sponge, thin terrycloth towel.This will not hurt your blender nor make it toxic. (Rinse or wash new sponges - sometimes the color bleeds)
I like to use cotton linters from Twinrocker but you can use other cotton linter, or cheap watercolor paper from a pad from the crafts store, or good paper scraps from your friendly print- or book-maker --- or just about any paper in a pinch but I really think you will be happier with something nice, like a good pure cotton. You will get good detail and no discoloration over time. You won't get a crisp result with paper towels, toilet paper, etc. I'd use copy paper quality at least.
Your first casting is your test casting to see how the mold works, so using pure white will make that easier - it helps you see detail.
Using additives is optional but I learned that I get the best results with a little methycellulose to help all elements of the casting adhere better. You must add it while the water is moving, using the hole in the lid of the blender. It takes less than half of a 1/4 tsp. measure for one blenderful of water. Some papermakers add a little PVA (white glue - teaspoon per blenderful maybe)
If you use sheets of cotton linter, you will need a piece a little larger than your casting mold. Don't worry about making too much as it's easy to save for another time.
Fill the blender with water, start it blending and gradually pour in a small amount of methycellulose if you have it. While it blends, put the lid on the methylcellulose jar and then put center plug back in the lid of the blender, and by then it will have blended enough.
Tear up the linter sheet into pieces about 1" and drop in. It takes a little experience to tell how much - probably not over about 6x7 inches total. If you are using paper instead of linter, it helps to let it soak a while. Blend until you feel it is pretty evenly soupy - maybe a minute. Pour into a strainer over a bowl or plastic container and shake around a bit until some of the water is out and it's a very wet lump. Dump into another container. You can put the water back in the blender and add more linter and blend again.
Set your mold in front of you, have some flat toothpicks (not round pointy ones), a clean flat sponge, and a fairly thin terry towel handy. Unless there are no narrow or deep parts to your mold, you will probably have to "toothpick" it to ensure a really crisp casting. This is done by taking a small blob of pulp and setting it near the part you are working on, teasing a little bit into a shape similar to the hole and putting it in. You can use fingernails for really tight bits, but mostly the toothpick works well to tamp it down in. Make sure you get pulp into all the corners and don't feel the hard clay of the mold when you push down with the toothpick. It takes a little practice but you can tell by feel and sometimes by look whether you have enough pulp in. You don't want it hard, just somewhat firm with no holes where the clay is not well covered. If your backing is colored, you shouldn't see the color through the pulp. Note: We are still filling only the holes or depressions in your mold. Sponge off excess water and push pulp all down in.
When you feel you have gotten all the depressions filled and sponged off to check, you will cover the whole mold with blobs of pulp. After initial "patting" down to make the blobs spread to cover it all, you should have it more than 1/4 inch thick all over.
You will need to gently slap it with the flat of your hand - you should hear "slap" and see some water flying. Think patting someone's cheek. Keep pushing it back in toward the middle from around the edges so it is within your borderlines or near your raised or lowered edging. You should slap it for some time until it becomes a cohesive sheet - you will tell a difference. Turn it so you are slapping from different directions. This takes a couple of minutes or so. If it just won't smooth out, you have gotten it too dry. All pulp put into or on the mold should be pretty wet. You should need to sponge up puddles underneath the mold now and then.
When you think it is smooth and cohesive, make sure it is all in close or within the edge you want, then make the "deckle" by using your fingertips to tap the outer edge until it is very thin, you should see the clay through it. If you see clay anywhere else though, add more wet pulp.
Check the evenness of your edges and then start sponging water out. Lay the sponge down and gently press, allow to come back up and suck out water. Squeeze it out into your container and move to a new spot. Now is the time your deckle "sets" so check it closely -- if you need to add pulp, make it very wet and pat into place. You can gently pull back if the pulp is too close or going off the edge.
When you are happy with your edge, continue sponging until you can't get much of any water out any more.
Now you "towel". Lay your towel on top of the pulp and press with fairly flat fingers all over your mold. Lift up, move to a dry part of towel and do it again.Now turn the mold, move the towel, and press more. Keep towel-pressing until it's hardly damp. You should be feeling depressions in the mold and see some of them and have a firm surface. If your fingers aren't tired you probably haven't done enough, especially if the mold is large.
If you are anxious to see it, lean the mold near moving air from a vent. I usually keep a stiff cardboard (or a tile) underneath as the clay will sag. A small fan is OK but often the edges will dry too fast and start to warp - you can put weight on the corners to help flatten while the rest dries. Do not try to take out your casting until it is quite thoroughly dry or the letters may stay in while the backing comes off!. I always allow at least overnight to dry unless there's a good reason to speed things up.
To remove the casting use something like a butterknife or letter opener to slip under the edges and work your way around and around, gently working it up.If it seems to stick, take your time, keep oging aroudn coaxing gently.. If bits do stay in the mold you can get them out with a pin and glue on with with PVA.
Other problems will be addressed in "Fixing and Refining Your Mold" to follow.
Feel free to send questions!
This is much easier to demo than to write about, you can get personal help and learn many variations on these basic techniques by having a workshop in your area.
Or, stay tuned for information about online classes where we will go step by step through several projects with feedback - not as fun as live workshops but it won't matter where you are, and there will be a "group" to experience it with.