This has been extremely important for several centuries and secondly to protect or decorate the pottery which is.
What is slip in ceramics used for.
In pottery the two most important uses of slip are.
A slip is a liquid mixture or slurry of clay and or other materials suspended in water.
The clay in the slip then shrinks away from the side of the cast and can be removed still retaining the shape of the cast.
Firstly to form the basic shape by slipcasting with moulds.
In slip casting a relatively thin slip perhaps the consistency butter milk is poured into a plaster mold.
The process of slaking clay to make it into slip is a simple one.
Score scoring clay involves slicing small notches into the clay with a sharp tool.
There are many ways to use slip to decorate ceramic pieces.
Slipcasting or slip casting is a ceramic forming technique for pottery and other ceramics especially for shapes not easily made on a wheel in slipcasting a liquid clay body slip usually mixed in a blunger is poured into plaster moulds and allowed to form a layer the cast on the inside walls of the mould.
Slip decorating for ceramic pieces.
If you work in a similar way i highly recommend learning how to make casting slip from your clay body.
It is used to determine specific gravity the ratio of clay to water in the slip and to measure viscosity the property of flow.
It has many uses in the production of pottery and other ceramic wares.
Like its cousin glaze trailing slip trailing applies material in lines using a slip trailer or other applicator.
The plaster mold then absorbs the liquid from the slip.
It should have the consistency of heavy cream because you are pouring the clay into a mold so you don t want it as thick as a decorative slip.
All you need is a 5 gallon bucket a drill with a paint mixer attachment a deflocculant and the clay body you want to use as a casting slip.
All of the following techniques can be used with both colored or non colored slips.
4 ounces of sodium silicate measured by volume weighs approximately 5 ounces on a scale.
Liquid ounce measuring cup sodium silicate for instance must be measured by the liquid ounce not by weighing it on a scale.
Preparing the casting slip.
Pottery stores sell special needle tools and scratch wire brushes for scoring.
The process usually takes at least 24 hours per piece.
There is also slip for molds this slip you want to be runny.
Another use of slip is called slip casting.
Slip used for decorating also has the consistency of well mixed sour cream unlike slip for molds.
Slip is also used to decorate pottery by painting the pottery with the slip and letting it dry creating a two tone look.
A more liquid slip can be brushed on sprayed on or pieces can be dipped in a container of slip.
The great thing about colored slip is that since it becomes part of the clay body it can be used in the plastic and leather hard stages with success.
A thicker slip can be trailed onto the object using a condiment bottle or other trailing applicator.
