[Lucille Oka]

What are the five developement stages of moist clay, to reach completed ware?

1.
2.
3.
4.
5.

If the question seems elementary to you then you are no beginner go wedge up some clay.

[Mark McCombs]

1. Wet clay
2. Greenware Leather Dry
3. Greenware Bone Dry
4. Bisque Ware
5. Glazed Ware

[Lucille Oka]

Very good Mark.

Ok newbies, next - Research Sgraffito what does the process entail?

Answer this question: Out of the five developement stages of clay, which one is the best to perform the process of Sgraffito? Taking into consideration safety and clarity of images. Why is your answer the best stage?

Homework: Make a Sgraffitoed tile.

Attention:
More experienced potters feel free to ask your own questions or provide your own mini seminars for the beginners to help them on their clay paths.

[Lucille Oka]

Sgraffito: to scratch. Here are some Youtube videos you may like. The first one is making a sgraffitoed tea pot. There are other examples on the side list or the screen menu after the first video is completed. http://www.youtube.c...h?v=VCPQm5s2SSQ

[Mark McCombs]

Lucille Oka, on 24 October 2012 - 03:15 PM, said:

Answer this question: Out of the five developement stages of
clay, which one is the best to perform the process of Sgraffito? Taking into
consideration safety and clarity of images. Why is your answer the best stage?

Homework: Make a Sgraffitoed tile.

On my last run I started to use various tools to mark or scratch patterns into the clay. Things I noticed:

1. If the clay is less than leather hard the piece became rather messy and difficult to work with. Edges were not as sharp as I intended. Cuts were hard to control.
2. If the clay was a little past leather hard, the tool would not cut smoothly and the edges would fracture leaving rough lines. Cutting motion was jerky and abrupt.

So to answer the question I will say leather hard. But within that answer, you have to know the clay body you are working with and when it is most receptive to that kind of treatment.

I have rolled out and formed a tile. I think I'll try to scratch out a fish.

[JBaymore]

To expand.......

Using the term "leather hard" seems to imply a "one state" situation. The drying of clay is a continuium from full wet state to completely bone dry. It is such a continuium that it would require hundreds and hundreds of individual terms to "categorize" each possible condition of the clay with a "name".

Different effects are achievable from a single process like sgraffito depending on the exact consistency that the slip and clay are at at any given point when you begin to use the process.

Technically you can do the scraffito technique on freshly applied wet slip on totally wet clay. It will have a particular character and require a specific way of handling.

The idea is to explore and learn the various characteristics throughout that continuium from full wet to full dry so that you can select the correct consistency for the desired effect.

best,

....................john

[Lucille Oka]

Mark McCombs, on 25 October 2012 - 11:59 AM, said:

On my last run I started to use various tools to mark or scratch patterns into the clay. Things I noticed:

1. If the clay is less than leather hard the piece became rather messy and difficult to work with. Edges were not as sharp as I intended. Cuts were hard to control.
2. If the clay was a little past leather hard, the tool would not cut smoothly and the edges would fracture leaving rough lines. Cutting motion was jerky and abrupt.

So to answer the question I will say leather hard. But within that answer, you have to know the clay body you are working with and when it is most receptive to that kind of treatment.

I have rolled out and formed a tile. I think I'll try to scratch out a fish.




Very good Mark.
I have used 'out of ink' ball point pins, pencils, and a wood stylus (usually comes in a larger wood tool set). I also thought about using a lace making crochet hook haven't done this yet. Leather hard is the best clay stage for me when I want to make angled shapes and lines just like in linocut as a matter of fact the lino cut gouges seem a perfect idea to try as well.

If you like your tile and want to install it, place ridges (keys) on the back so that the mastic will adhere better. Who knows maybe you can do a whole school of fish; all types maybe tropical and colorful. You can allow the sgraffitoed lines to create cells or islands to apply color in an on the claypieces.


Next lesson: Sprigging

Define Sprigging.
How can you use it in your work? Can you combine both in one project, Sgraffitto and Sprigging? How about making angel fish?












[/quote]

[Pres]

JBaymore, on 25 October 2012 - 03:16 PM, said:

To expand.......

Using the term "leather hard" seems to imply a "one state" situation. The drying of clay is a continuium from full wet state to completely bone dry. It is such a continuium that it would require hundreds and hundreds of individual terms to "categorize" each possible condition of the clay with a "name".

Different effects are achievable from a single process like sgraffito depending on the exact consistency that the slip and clay are at at any given point when you begin to use the process.

Technically you can do the scraffito technique on freshly applied wet slip on totally wet clay. It will have a particular character and require a specific way of handling.

The idea is to explore and learn the various characteristics throughout that continuium from full wet to full dry so that you can select the correct consistency for the desired effect.

best,

....................john

Going along with this expansion of the state between wet, and leather hard, one of my favorite working times is the "cheese hard" state where the clay will support itself, yet still gives.

Often when doing sgraffito where I want clean lines, and edges in dry clay I will use a flexible shaft attached to my dremel with a small fine bit. A little dustier for sure, but much faster, and more fluid. Just don't use too hard or you'll end up with pierced designs. When thinking sgraffito, I also enjoy the opposite technique-Mishima which is also quite stunning when done well.

[Mark McCombs]

After I coated the tile with a Cobalt slip, I allowed it to slowly dry, testing the clay every day to see if it was ready.

I traced a fish on the tile today and then scratched around the design.

There is some clean up to do as it finishes drying and I will fire the tile this next weekend.

[Lucille Oka]

You do understand that the clay doesn't have to be dry in order to do sgraffito? And it is safer when dampened there is not so much dust. If you are going to do anymore of this method in the dry stage be sure to use a respirator and goggles.

To me cobalt is the most beautiful of all the ceramic colorants; it is my favorite. But it does 'spit' while firing in the kiln; I don't mind it. However it doesn't discriminate. The 'spit' lands anywhere so be careful that it doesn't 'spit' on your elements it maybe a good idea to cover the tile with a larger vessel, (use as a saggar) and place upside down and over the tile.

Define-saggar

[Mark McCombs]

Lucille Oka, on 30 October 2012 - 11:18 PM, said:

Define-saggar

How funny. I was just reading up on the use of saggars for reduction atmospheres in an electric kiln.
Something I will definitely try in the future. I need to buy/design/build one or two saggars for bottom shelf.


As far as the tile goes, I had it in a plastic bag drying VERY slowly. It was damp for sure and carved quite nicely.