September 8, 2008
Slip Trailing for Beginners: A Primer on a Great Ceramics Decorating Technique
The Beauty of Slip
This simple clay and water mixture is a wonderful decorating tool
because it allows for tremendous personal expression. Although slip can
be applied by using all of the same techniques as a glaze, the slip
trailer and commercial applicators offer a lot of great opportunities.
Slip trailing is the application to a clay surface of lines of slip using a fine-pointed dispenser. It differs from glaze trailing in several ways:
Slips are generally applied to leather-hard work, even though some can be applied to bone dry or even bisqueware.
Most slips do not move, run or flatten out during the firing. What you see is what you get.
The raised surface creates physical as well as visual texture.
Since the color is mixed with clay, it stays in place when dry and doesn’t dust off when rubbed.
When bisque fired, the slip becomes part of the pot and stays on even when scraped.
These characteristics create a decorating technique ideal for designs requiring precision, such as commemorative plates. Planning ahead lets you put slip to work for you and make the most of its qualities.
If you’ve never worked with slip before, it takes some getting used
to. Here are five simple steps that will help you get started:
Become familiar with how a trailer works.
Develop an idea of what you want to create.
Practice on a slab.
Try it for real!
Getting Started
The tools and materials needed for slip trailing are simple and can be purchased (See “Supply Room” in the latest issue of Pottery Making Illustrated) or even fabricated in the studio. You can make an inexpensive slip by soaking dried scraps of your clay body in water. Let it soak until it’s a slurry and stir. Screen it to remove all the lumps and grog and store it in an airtight container. For a simple trailer use a condiment dispenser available in most large kitchen departments.
If your trailer is not filled, remove the tip, squeeze the bottle
and insert the top of the trailer in the slip container. Ease off the
pressure and allow the trailer to draw in the slip then replace the tip.
To use the trailer, grasp the bulb or sides of the bottle, shake the slip down toward the tip, tilt the trailer to one side and gently squeeze. You can drag the tip on the clay as long as you are moving it away from the open end, so the slip is trailing out behind the applicator as you create a line. If you move it the other way, the tip will dig into the clay and get clogged.
Before creating a design, practice using the trailer on a slab of leather-hard clay. Get a feel for how the slip comes out and what kinds of lines you can make with it. Spend time playing with different hand motions. If you’re used to a brush, using the trailer will feel a bit awkward at first. It takes practice to squeeze with the right pressure and move your hand at a steady pace to get a smooth line. After a number of tries, you may decide that the applicator is too big or too small for your hand. If that’s the case, find one that’s comfortable to use.
Once you’re done experimenting, make a test tile with brushwork and
trailing with each slip you’re working with. Make one tile for each
glaze you want to try, plus an unglazed tile. If you have any pinks,
lavenders or purples, make sure that the glaze is zinc-free or the
color will shift. I test all slips on wet, leather-hard and dry clay to
give me an idea of the moisture range they can tolerate, and a soft
leather-hard clay worked for all the materials tested here. You need to
experiment to see how your slip works with your clay.
Judi Munn is a potter living in Mountain View, Arkansas.
Tags: Judi Munn, slip decoration, slip trailing










Steven | November 15th, 2009 at 10:00 pm
I used a white slip which turns white after a bisque or glaze firing. As well as the white with oxide making the color black. Both slips when applied were thick enough to smoothly lay down like a small log or better yet a long log. After 24 hours the panda bear and the small leaves he was eating looks like flat tires, like the logs got deflated. The areas were I pushed the most slip onto the bowl with the bear inside were not log like the next day but more like a small lake one black and one white that were in a drought and now were empty and just damp and cracked. Why is this happening? I thought there was additional elements or compounds of dry or wet to add to a slip in order to get it to act like slip is supposed to act!