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Slip ‘n’ Surfaces Week 4

It’s been a great class with really wonderful students. I’m always so thrilled to see what they are working on each week. Since this was the last week, I reall packed in the demonstrations.

Banding

I started off by throwing a bowl with about 3 pounds of clay. People wanted a refresher in how to throw a larger bowl. This was a good item to demonstrate banding with slip  while it was still on the wheel. One of the most common and annoying problems with banding is that the slip doesn’t just glide on there in a steady stream leaving a perfect highway of color on your pot. Especially if you are applying it to a leather surface, the clay can suck up the moisture from a thicker slip and give you a very uneven, often kind-of pitted surface.  If you are applying to leather hard it helps to spritz it with a bit of water ; wait a few seconds for the water to sink in a little, otherwise you lay your slip down onto a thin layer of water and it can drip and not stick well.

If you are applying to a freshly thrown pots (which is ideal for bonding for porcelain slip bonding to stoneware) you still have to dip the brush more frequently than you’d think. Just keep the wheel going steadily and hold your hand steady too. You can always clean up the edges with a metal rib or stick tool. Here I used my rib to put a little wavy edge on my band.

Leaf Stencils

Next I threw a low terra cotta bowl so we could do some stencils using leaves. I also showed how you can take something like a fork and with an even motion while the wheel is going slowly, make another kind of border around the rim- this time on the inside. 

I had  some problem getting the leaves to really lay flat but Kristina solved that problem by using some newsprint to really presss her leaves down flat.

Here is the plate after she pulled the leaves off

Beautiful. She will go back in when the slip is leather hard and clean up any places the slip snuck under the leaves.

Jennifer put some on the outside of her mugs which also turned out great. It’s important to think about how the leaves will fill the space. I think all these examples (except mine) are excellent.

Marbelizing

Another thing you can do with two or more colors of slip is to marbelize- like the fancy paper you often see. I think for this you need a fairly flat, contained surface. I had a small stoneware plate  which I poured some blue slip into and then dotted and trailed green on top of that in a fairly random pattern. then I dragged a very pointy brush (you could use a feather or pointy stick too) through the dots.  I was inspired by plant forms.

When I trim the plate, I’ll go in and clean up the edge of the inside too.

The one thing to be careful of when marbelizing is that it adds a LOT of moisture to your pot. Make sure your form is supported or dry enough to absorb that moisture and keep its shape.

Etching

Then I did my surprise demo. This was “etched” clay. Really, I would only recommend this technique for porcelain as you will soon see why. I threw a tumbler and set it to dry. When it was hard leather dry, I painted a pattern on it in wax. After the wax was completely dry (and you can do this technique with varnish was well)  I began wiping at the surface with a wet sponge. The wax protects the surface beneath it but the surrounding surface is removed. If this was stoneware, it would just be horribly gritty.

After a few wipes, I decided to scratch into my wax a little to get a more detailed resist area. 

This will look great with a breaking glaze like Shino, Celadon or even Josh Green.

Kelly took this idea and ran with it – here is her process: and she got the brilliant idea of inlaying black slip into the wiped away areas. She painted it on and the wax resisted it over the raised areas. She sponged away all non-adhering slip and here is the resultDoesn’t that look cool?

Another variation on this idea is to paint your entire surface with slip, then a pattern over it in wax and then when you wipe away, you leave the color where the wax protects it and the color is removed everywhere else. Kristina suggested this and I can’t wait to try it!

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First Time Potter Week 2

TRIMMING

This week we first learned about trimming since we started with bowls last week.

It’s always a toss-up;   bowls are easier to throw but you really should trim the bottoms. Cylinders are harder to throw but you can make them so that you don’t have to trim them.

The first step in trimming is often forgotten.  You should take a really good look at the inside of your pot- I’m going to say bowl here because that’s what we’re trimming. Take a look at the shape of it, try to feel the thickness of the walls and bottom and then turn it over.  The reason you are memorizing the shape as best you can is that you will be trying to make that same shape on the outside so that your bowl eventually has even walls and the foot should be like a little ring of clay sitting on the bottom of your bowl.

Next, center your upside down pot on the wheel head. Many potters can “tap” their bowl into the center- this is a huge mystery to me.  I have never mastered this amazing skill.

Instead, I hold a pencil steady and where it makes a line, I slightly push until it’s even all the way around. Then I press clay down around the bowl taking great care not to deform the rim- press against the wheel head, not the rim.

Now tap on the bottom gently, Eventually you will be able to “read” the resonance as to how thick the bottom is.

Now look at the curve of your bowl. You want to continue that curve. you don’t want your foot to be so wide that the curve doesn’t have a chance to get started. You also don’t want your foot so narrow that you have a super-tippy bowl. There is a lot of wiggle room here- it ranges from  mixing bowls that have nice wide sturdy feet, like sensible shoes all the way to little rice bowls which have delicate feet like party pumps that you can dance in.

Draw the circle that will be your foot on the bottom and then

choose a loop tool you are comfortable with and begin to carve away the rest – do not touch inside the lines that delineate the future foot! Remember you are trying to mimic the curve that is going on inside your bowl. this picture is a little confusing because I am holding two tools but only using the big loop tool  at that moment. Sometimes I alternate between the two so often that I am holding them both while I trim. I am not using them both at once!

Once you have the shape you can use a wider loop tool or even a metal rib to smooth it  and also use your fingers or back of your nail to smooth any rough edges on the foot- you don’t want to scratch your mother’s coffee table!

Cathryn did a great foot right away!

Adrienne did too- and it’s one of those delicate feet.

The two most common mistakes are not trimming enough and

trimming too much as one of the students found out to her chagrin:

Steve needed a foot thrown on so I demonstrated that- I did a post about that some time back….

CYLINDERS

Then we tackled cylinders. I started by making a pitcher with a curved floor (as opposed to a flat floor).

You start this like a bowl but then bring the walls straight up.

After you collar it in, use a tool handle to make a simple spout.

Cylinders, because of centrifugal force, inevitably want to get wider. it is helpful to collar in at the top after every pull as well as compressing the lip to keep it strong.

Next I did a vase with a flat bottom inside- The trick to vases is to get them as tall as you can and then instead of just choking it in at the top, you must coax it inwards, keeping the wall arched for good support- just like a cathedral!

the finished vase shapeLater, I will trim the bottom a little but I will trim it while it is right-side-up on the wheel so that I don’t have to use a chuck.

Lastly, the simplest and most realistic cylinder for beginners to make is a mug. A mug takes about 1lb to 1.25lbs of clay and is a great way to practice vertical pulls and later, attaching handles!

Special thanks to Melissa for taking the photos and also being pretty darned funny!