Rolling Coils That Don't Dry Out or Fall Apart
Okay, so we're leaving slabs behind for a while. New module, new set of problems, and honestly some of you are going to like this better. Coils are more forgiving than a slab wall in some ways and more annoying in others. Let's get into it.
A coil is just a rope of clay you roll out by hand and stack to build a wall, instead of cutting a wall from a flat sheet. Same wall, different method. The whole appeal of coil work is that you can build up, correct as you go, and change your mind about the shape while it's still happening. You can't do that with a slab once it's cut.
Rolling the coil itself
Take a lump of clay about the size of a golf ball, less if you're a beginner. Set it on the table, not on canvas, not on a towel — a smooth, slightly damp surface works best. Flatten it a little with your palm first so you're not starting from a perfect sphere.
Then roll it out with both hands, flat palms, moving from the center outward in both directions at once. Even pressure. This is the part people rush and it shows. If you press hard in the middle and light at the ends, you get a coil shaped like a carrot, thick in the middle and tapering off, and that's going to give you an uneven wall.
Aim for something like the thickness of your finger, maybe a little thicker for a bigger piece. Roll until it's the length you need for that section of the wall, usually somewhere between six and twelve inches before it starts wanting to break or get too thin to handle.
Here's the thing: if it cracks while you're rolling, it's too dry. Wet your hands, not the clay directly, and try again. If it keeps cracking, the clay itself has skinned over somewhere and you need a fresher piece from the bag.
Attaching each coil
You already know this part, mostly. Score the top edge of your wall, score the bottom of the new coil, slip both, press together. Same rule as always, no exceptions, and I'll say the opinion straight out because I say it every module: score and slip every single join, no matter how minor it looks or how confident you're feeling. A coil wall is nothing but joins stacked on joins. Skip scoring on even one of them and that's exactly where your kiln crack shows up later, weeks from now, when you've forgotten you cut a corner.
Once the coil is pressed on, blend it into the wall below with your thumb or a rib tool, smearing the clay from the coil down into the wall so the seam disappears. Do this on the inside and the outside both. If you only blend the outside, the pot looks fine and is structurally a liar, because the inside seam is still a weak line waiting to separate.
Keeping it from drying out mid-build
This is the part that trips people up at home, more than the rolling technique does. You're going to roll a coil, attach it, blend it, and then go answer the door, or check on a kid, or get distracted for ten minutes, and by the time you come back the top of your wall has skinned over. Now your next coil won't bond right no matter how well you score it, because you're joining wet clay to something that's already lost its moisture.
Up here at our elevation, with air this dry, that skinning happens faster than you'd think. I've lost work to a ten-minute distraction more than once. Cover everything you're not actively touching. I buy the giant multi-pack of shower caps at Costco for exactly this — they stretch over a bowl or a coil pot better than plastic wrap does, and nobody believes me until they try it. Get a pack. It's cheap and it will save you a cracked pot eventually.
A word about tools, and about Wyatt's slab roller
You don't need anything fancy to roll a good coil. Your hands are the tool. A rolling pin helps if your hands get tired, but plenty of people build entire pieces without one.
I'll admit I'm biased toward cheap tools generally. Wyatt once built me a slab roller out of two dowels and a cutting board, before I owned a real one, and it was genuinely bad — uneven pressure, dowels that rolled crooked, the whole thing. I used it for a year anyway because he'd made it for me and he was so proud of it that I couldn't bring myself to switch. My point being: don't let anyone convince you that you need to buy your way into this skill before you've even rolled your first coil. Get a feel for the clay with your hands first. Buy the good tools later, once you know what you actually need.
Don't chase a perfectly even coil, either
Your coils won't come out identical to each other, especially the first dozen times. That's fine. A slightly irregular coil wall reads as handmade in a good way, not as a mistake. Fix a crack. Don't sand the personality out of it trying to get a machine-made look, because that's not what this method is for.
Before next time: roll ten coils at home, just rolling, no attaching, and see how many you can get even along their whole length before they break or taper. Keep them under plastic or a shower cap between attempts so you're practicing on fresh clay each time.
~erin