Welcome to Ceramics Tips

Carving without burrs

When carving into leather hard clay, first cover the surface with plastic Wrap. You can draw your pattern on it with a marker. And when you carve there will be no burrs.

Attaching pulled handles

Attaching pulled handles:
Once all handles are pulled and firmed, (approx.1/2 hr), they are ready to attach. I will describe this process as connecting to a mug, though it is the same procedure no matter the form.

1. Take handle and flatten the large end with a flat piece of wood ie ruler, wooden spoon back.
2. With a fork or other tool cross hatch both the flattened end of the handle and the point on the pot you wish to attach the handle, with an old toothbrush, wet these areas with water or slip.
3. Attach the hatched end to the pot and press and wiggle it gently until you feel adhesion
4. Pick up the pot and hold arm extended as when pulling the handle, and continue pulling in the same way until desired thickness, squeeze off any excess clay and join other end to pot by pushing into place.
5. Leave upside down to dry.

Note: Handles dry faster than ware,
so keep them covered with plastic or put on ware board with all handles facing inward.

Make a wareboard

Wareboards: These are invaluable for transporting, drying and storing ware.
Best made from Marine ply 4 gauge is enough, 1m x 50c, is a good size. Cut out with jigsaw.
Cut 40cm long x 4cm dowl in half and nail 10cm in from either side (this gives a fingerhold and is easy to slip into frames (If you´ve been ingenious
enough to build them )

Keeping slabs useable

Make slabs in advance and keep them wet for ages in Styrofoam coolers. If they start to dry out, throw a wet towel over them.

Simple round mold: step 3

Once you have your plaster poured, you simply place your balloon or ball (if a ball is used it would be advisable to seal it with soft soap before use), into the plaster to half cover the ball. You can tape it into place while the plaster heats, cools and sets.
Remove the ball or balloon and container, scrape off any rough spots, leave to dry in a cool dry place for a week and it will be ready to use.

Joining

Joining two pieces of clay presents more challenges. If the clay is quite moist--not much drier than when it comes out of the bag, we can usually just smoosh it together and smooth out the seam. But if the clay has dried a little, such as when adding a coiled foot to a bowl or joining the corners of a stiff slab box, we need to take care when joining the clay. The surfaces to be joined should be thoroughly roughened by scoring with a serrated rib and moistened with slip. It´s a good idea to repeat the scoring again after the slip has a chance to soak into the clay. Daub on a little more slip and firmly join the pieces. If possible, it´s good to compress the seam by smoothing it with a tool or rib or by paddling it gently.

Slab Mug

This slab can be rolled from agate ware, textured slab or plain slab.
1. Cut a template of the shape, obviously straight to triangular shapes accomodate this proceedure better.
2. Cut 1/2" slab to required template. Form to desired shape.
3. Join seam in mug body as shown in joining tips.
4. Cut base to suit.
5. Join base to slab as shown in slab joining tips.
6. Leave to leather hard.
7. Add handle

Your work is now ready for firing!

Materials for basic handbuilding

BASICS:

1) A smock (old long shirt, overalls, apron) (to keep your cloths or nude body from
getting smeared in clay
eeeeeh)
2) Hair tie or scarf (to keep those pesky little suckers out of that masterpiece)
3) Handtowel (for drying hands if the phone rings)

4)Rags (for those unexpected messes)
5) Small plastic bucket (for water to rinse your hands, when they get too mucky)
6) Sponges ( for spills and keeping surfaces clean)
7) Tabletop (wedging, rolling, cutting)
8) Weigh scale
9) Claycutter (2 washers and picture wire)
10) ceramictile/s, or wooden ware boards (for drying pots)
11) clear plastic bags, or plactic groundsheets cut into convenient sizes (for keeping pots from drying out)
12) Kiln
- electric (low fire, medium fire, high fire)
- gas(low fire, medium fire, high fire)
- woodfired(low fire, medium fire, high fire)
OR - raku (low fire, medium fire, high fire)
just bisque firing stage

Firing lead free glazes

Firing lead free glazes
Changes In Glazes:
Lead free glazes are becoming the standard for commercial use. This is due to government regulation and health concerns by the manufacturers. As the name implies, lead free glazes are made from compositions or materials where lead has not been added.

To eliminate lead, glazes are reformulated. This can change some of their properties. Some of the differences you may notice include:
Does not flow or run as much in firing as lead-containing glazes.
*Brush marks may show after firing
*Not as wide a firing range
*May not be compatible with as many bodies (improper fit). This leads to shivering or crazing of the glaze.
*Colour does not match lead glazes
*More surface defects

For problem-free results with lead free glazes, firings must be more closely controlled and kilns well vented. Bodies may have to be bisqued to a higher or lower cone number to solve a problem.

Basic preparation

Slabs
One of the easiest techniques a potter incorporates, this technique is used for a
multitude of purposes....from a basic flop moulded bowl to intricate formed plaster
relief slabs that are then made into boxes or sculptures.(See the work of Gabrielle
Schitzenbaumer)
The simplest method of rolling slabs is of course a slab roller, if you have access to
one, but most of us use the rolling pin method. A large rolling pin is needed without
moving parts. Also 2 wooden boards 1 inch wide x 1cm thick, these are used as a
rolling guide.
Cut a piece of clay from your block, pace a cloth over a flat surface(this stops the
clay from sticking to the surface) and roll from the centre outward, then turn the slab
over and procced as before.....repeat this process until the clay slab is approx 1.5 cm
thick.
Place roller guides on either side of slab approx 1cm from the sides and roll flat.
Your slab is now ready to use!

Burnishing

Burnishing

The technique of burnishing pottery can be traced back to ancient times.

Burnishing involves no more than rubbing the clay surface with a smooth tool to produce a mirror-smooth surface. In reality it has a compressing effect on the clay particles. It can be done when the clay surface is leather hard and up until it is almost completely dry. Most clays are suitable for burnishing although the finer the clay the smoother the burnished surface.

Suitable tools for burnishing include: Smooth rounded
beach pebbles, The convex side of metal spoons and smooth knife handles.
After the pot is smooth, draw your design with lead pencil then scratch around design with a knife. Designs can either be geometric or organic. Once the pot has been blackfired it can be left without further
treatment or polished with oils to enhance the shine.

Achieving clean cuts

When cutting clay pieces, first dip your knife in vegetable oil so it glides right through the clay. WD40 works also, but has a chemical smell. Both will burn off in the kiln.

How to make a slab box

Slab box:
After rolling your slab, and you can roll with a pattern by simply placing leaves or a
crocheted cotton tablecloth or such like ove the clay and roll gently but firmly, this will
give a textured slab. Leave the slab to become firm, approx 1 hr.
While waiting, make a template of the shape you are aiming for (be as precise as
possible as it makes the job a lot easier in the long run.)
Place the templates on the slab and cut around them with a sharp knife and a ruler as
a guide.
Each side that is to be joined must be bevilled to a 45degree angle.....this is achieved
by placing a ruler approx .5 of a cm in from the edge and cutting at that angle to the
table surface.
All edges to be joined have to be crosshatched with a fork, so they are rough, apply
slurry or water with a toothbrush and firmly press the sides together. roll a thin coil,
dip it into water and gently apply it over the join then smooth. Continue in this way
until all sides are joined and you have a hollow cube, leave it to become leather hard
when you are satisfied with the form.
With a sharp knife cut the top off the form, keeping in mind to mark one side so you
know which way the lid goes back on. clean the edges. and make small balls of clay
to press into the corners of the lid, and go down into the box as the lid fasteners.
You have made a slab box, leave it to dry thoroughly and it is ready for bisquing!

Oxide colours

Our glazes and clays are colored by the oxides and carbonates of various metals. Iron oxide is red, cobalt carbonate is lavender, copper carbonate is green.... These are what give the un-fired clay and glazes their colors. If we adjust the burners and damper of the kiln to fire the kiln with excess oxygen--enough to burn all the fuel, plus some--the metals will take on their most oxidized forms in the fired clay and glazes. This is called oxidation firing. Copper glazes will be green, and iron bearing clays will be orange, red, or brown. Electric kilns always fire in oxidation.

Firing Issues/cracking

Firing Issues

Is the ware fully dry?
Ware that is not adequately dried will crack or explode during the early stages of firing. Water inside the pores of the ware turns to steam, exerting pressure inside the ware. To fully dry a thick walled piece, the ware needs to be warm for more than 12 hours.

Agate-ware: Stained

Agate ware is a decorative ware made from partially blended dark and light clays which give striations. The effect is sometimes created with surface slips. The name comes from the semi-precious agate ston, a form of crypto-crystalline quartz with striated markings.

Though agate ware can be made by using different stains to achieve the colour variations mentioned above.

Procedure:
1. Wedge 3 kg fine white earthenware clay.
2. Cut into three.
3. Add stains to desired colour to the three batches.
4. Roll slabs of the three colours 1/2" thick
5. Cut the slabs into 1/2" wide strips.
6. Align the strips into a pattern and roll, turning frequently to join.

This slab can be used as is, in a slump or hump mold, or can be further dissected into a patchwork design or made to order with colours purposfully positioned to form a decoration or drawing.

Have fun with this as it is a wonderful technique and one well worth mastering!

Rolling

If you like to work on pieces of clay that require rolling to form thick sheets for cutting out flower petals and leaves, you may find that the clay sticks to your roller. Next time, try putting a piece of plastic between the clay and your roller to prevent this from happening.

Thick pieces/Cracking

When did cracking occur?
Often the crack itself can be examined to determine when it occurred. If the edges are sharp, then it probably occurred during cooling. If the edges are rounded or if the glaze has flowed into the crack, then it occurred during heating.