Don't forget to resister for the next section! Starting November 16th!

Intermediate/Advanced Handbuilding Techniques - Secrets Revealed Wednesdays, 1 - 4 pm, Class #D15 Patti Nelson

From the beginner to the experienced- Find out how to make your ideas into reality!

This class will reveal secrets of top ceramic artists for more successful hand building. From building large, to building thin and strong, patch and repair, avoiding cracks, plus paper clay, staining, marbling clay and much more. This demonstration/tutorial class is sure to inspire and stretch imagination and skills for functional and sculptural artists at all levels.

 Special Projects in Slip and Plaster Wednesdays, 7 - 10 pm, Class #E16 Patti Nelson

Every had an idea and had no idea how to do it, been told it couldn''t be done? Or couldn't be done in the class that you were in?

Join us in this class with no boundaries! Learn to ask not if but how!

Designed to introduce functional and sculptural artists to the range of possibilities in working with slip and plaster. Students will learn to utilize plaster as a tool in simple and complex mold making, (slip and press molds), and as a tool for pushing the range of using clay and casting slip functionally and sculpturally. Additionally, slip will be introduced as a material to be combined with organic materials (from flowers to fabric) to create forms without limitations. Potters and hand-builders alike will find tools to expand their current work with embellishment and production methods, as well as having new ways of working presented. Whether you have ever made a mold or not, you are sure to find exciting new possibilities in this class. Pair new skills with wheel, hand-building or other methods you have loved in the past to expand your universe!

Ruth's Giant Gourd!

Figurative artists to look at...

http://www.arniezimmerman.com/

http://www.nolenstudios.com/

http://sergeiisupov.com/

Where to buy stuff...

http://www.theceramicshop.com/store/




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The other place to buy stuff if you want more options is Ceramic Supply of Ny & Nj, Lodi, NJ.  You will most likely have it delivered if you buy it from here...

http://ceramicsupplyinc.com/

Great Artists to look at!

http://www.anellegandelman.com/anat.html

http://www.claretwomey.com/

Judy Moonelis

http://www.nualaodonovan.com/

http://www.juliakunin.com/

http://www.gallery4allarts.com/andrea%20szocs.htm

Plaster 101

What is plaster:

Plaster comes from a naturally occurring mineral state. Pottery Plaster #1 is a Gypsum based plaster.

When it is heated to about 300 degrees f it becomes a powder.  The water of crystallization has been removed.

When you re-hydrate the material, the molecules are able to take up this water, and form new inter-locking crystals. This we recognize as set plaster.  These interlocking crystals are a chemical reaction and create a sponge like quality that work to absorb the moister from clay.

Heat and cold will break down this structure.

In order for plaster to have the relationship with clay that we want, it is important that it is mixed in a way that the correct crystalline structure is developed.

To Mix:

Make sure the plaster feels soft and powdery (if there are hard lumps it may have been exposed to moisture)

Measure a little less water then you think will fill up the area you want to cover

Slake the plaster into the water, not too slow, not too fast-breaking up any lumps as you go

watch for the chemical reaction to occur where the plaster starts to sit on the surface of the water (not just a lump in the middle of the plaster)

Let plaster sit in water 2-3 minutes

Agitate until you can see a finger trail in the slip that disappears quickly

Mist with rubbing Alcohol to pop bubbles

Pour steadily into your mold, trying not to create air bubbles

Agitate the mold

Mist with rubbing Alcohol to pop bubbles

You can release carefully when warm or after warmth has cooled (anywhere from 20 min- 1hour)

Wet sand to clean up and compress plaster.

Mold Making

3 things to consider:

What is the material the positive is made from? Is it porous, non- porous, and will the heating of the plaster possibly cause and expansion?

What does the object look like- does it have undercuts or details that are important to maintain?

What is your plan with the final objects?  Do you need the objects to be soft for further modification?  If so, you may need additional parts of the mold for easy release.

1.     Decide if you want to use a clay bed to lay your object on or if you want to lay it directly on the surface (the clay bed is easier to seal. 

2.     Soap your object if porous. Polish it to a silky finish.

3.     Determine where your walls need to be for each section before you start.  This will ensure that you are working smart not hard.  Use a clay maquette or a sketch to help you.  If you don’t care about the object you can also use a sharpie directly on the object.

4.     Using slabs, create walls for each section.  Be careful to seal each section (rubber finger tools work great for this.) Mix and pour plaster one section at a time. Let each section set up.  Make keys, then pour the next section.

5.     Use the amount of clay it takes to properly caulk any cracks.  Wipe away any extra clay.  A small amount of clay can seal without creating a large seem.

6.     After the mold has been poured and has set, gently vibrate the mold apart.  Remove the positive.  Put the mold back together for cleaning so that  you don’t inadvertently clean the fettle lines (the place where the mold pieces meet up on the interior of the mold. )

Sanding the mold compresses the mold, gets rid of plaster that might chip off, and helps it to last in the future. 

Slip:

Even store bought slip should be sieved before use.  This eliminates lumps that will have to be sanded out later and allows even water distribution. 

Deflocculate: To literally break up the “flock” of clay particles by creating a negative charge and causing particles to repel each other.  This allows us to add less water with more fluidity and allows particles to bond with better compression and with out air bubbles.  We add this deflocculant to slip (Darvan or Sodium Silicate)

Coddle: The objects which contain our plaster while it sets around the object we are casting.  Sometimes Aluminum Flashing, or boards we clamp together.

Fettle: The seam of the mold. 

Fettle Line: The line of an object where the undercut occurs (often still visible on plastic cast objects, such as pens)

Undercut: The point where if an immoveable object (such as set plaster) is wrapped around it will become locked and cannot be removed.

Key: the small indentation that keeps a mold from sliding apart.  Two primary types: Standard Keys and Slide Keys.