Thursday, January 31, 2013

January Hints of the Week


December 30th Hint of the Week
 Throwing Ribs by Idaho potter Brad Sondahl (http://sondahl.com)
“Ribs, or kidneys (or whatever part of the beast you like to eat), are used to smooth thrown clay surfaces, and to reduce friction while bellying (forcing) out a pottery shape. Most of the ribs I use are made from plastic, and the main source of sturdy plastic is credit cards. Prepaid phone cards are a good source. Tip: On any usable credit card, make sure you cut off the number, or wear off the magnetic strip, to prevent misuse. No amazing procedures here: Cut with a scissors and sand if the edge is sharp.”

January 6th Hint of the Week:
 Clean Up Scraper (From Idaho potter Brad Sondahl's Pottery Tips)
When it's time to clean off bats, or scrape the clay wedging area, a good scraper makes it all easy. To clean a plywood wedging area, a drywaller's broad spackle putty knife works quickly, and is ready made. For use on the wheel, I prefer a small scraper to scrape the bats while they spin, just before use.
  • Health Tip: To reduce the hazards of clay dust when cleaning bats, use your sponge and stick to moisten the clay left on the bat before scraping.
  • To make a comfortable scraper, take a piece of one inch wood about the size of a credit card.
  •  Smooth the edges by sanding, planning, or filing.
  • Placing the wood in a vise, make a cut with a hand saw approximately one inch into the wood. (See Figure 7).
  • Insert credit card into the slot. Glue in the card, or drill two holes as shown to hold the card in.


 





  January 13th Hint of the Week:
 Some Glazing & Decorating Stuff from Pottery-Magic.com.
·       Before you begin glazing always be sure to wipe your ceramic piece down with a damp sponge. This will make sure that there is no dust on your piece which could cause the glaze to pull away and leave a bare spot. Dampening helps the bisque to accept the glaze.
·       If you are painting on glaze, you must paint on three flowing coats of glaze, being careful of brushstrokes which could show up in unleaded glazes or if you use less than 3 coats. Three coats of glaze will give you a solid color. Adding another glaze for the second and/or third coat will give you some interesting effects. Let each coat dry before adding a second. Best to brush in opposite direction
·       To show textured surfaces better, brush glaze on so it gets in all the cracks, then wipe off the top surface.
·       To remove oxide mistakes or for making a design, use a pencil eraser. It won't smear like trying to wash the oxide off.
·       When applying oxide over dry glaze, the glaze sucks the water out of your brush making it difficult to paint clean lines. To remedy this, lightly mist the glaze first with water and the oxide will flow smoothly.
·       When glazing a thin piece, glaze the inside then wait for it to dry thoroughly before glazing the outside. Otherwise the clay will become saturated and your piece will either fall apart because it will have absorbed so much water or the glaze won't absorb and stick to the outside. It is best to at least let it dry overnight before glazing the outside.

January 20th Hint of the Week:
    HERE ARE SOME GENERALY GOOD IDEAS
·       Mark all of your plastic clay bags with a “Sharpie”, even if they are still in the boxes. Mark the cone number (∆) & what clay it is. It is also a good idea to put your name or initials on the bag. We often find clay left out, or get donated clay, or abandoned clay, etc. If we don’t know what it is, we really can’t use it, & if you forget what it is you may not be able to use it either. If you put the wrong clay in the wrong kiln firing the earth will tips off its axis.
·       Mark all of your tools with a “Sharpie” or some other way. There is not a day goes by that we don’t find an unmarked rib, wire, pin tool, etc. It’ll save you time & money if you can get your tools back. There is a lost & found drawer in the green admin area.
·       Keep a glaze log. Writing the glazes you use on a little scrap of paper or thinking you’ll remember what glazes you used, doesn’t usually work out well. Most of the potters keep some kind of a glaze book to record the clay & the glazes they use before they fire. This makes it very easy to go back & figure out what you did. It is also a good place to make comments after firing, even if it’s “I’ll never do that again.”
·       When you dump out your slop bucket or wheel tray of clay water pour it through the screen & you’ll catch those tools before they disappear into the “black hole” in our trough. Since we’ve put that screen there the boys that empty out the trough are finding significantly fewer tools. Although lost tools are an incentive for the boys to go tool diving while emptying clay.
·       If you put some newspaper on the floor & walls of the spray booth it makes it much easier to clean up afterwards. You also need to take down the papers before they are too loaded with glaze.
·       If you put plastic or a plastic bag over your wet pieces, sometimes the plastic sweats & the moisture goes right back on to the piece. Try laying a piece of newspaper over the clay then put the plastic on. Paper will catch the water drops before it gets back on the piece.
·       If you use the wall mounted extruder it takes quite a bit of clay to get it going & there is always a bunch of clay left inside when you are done. Put an open plastic bag around the upper part of the clay down to the die & then a large wad of plastic at the top of the clay in the bag. This will keep a lot of clay from sticking to the sides of the extruder & the extra plastic on top will give you more volume to push all most of your clay through.
·       Don’t put your pieces to be bisqued or fired right on the front of a shelf, especially large pieces. Pieces on the front with space behind stand a greater chance of getting damaged as other pieces have to be put behind them or are lifted over them. Pieces on the front don’t necessarily get fired quicker either.


January 24th Hint of the Week

Using Tape Resists (From Big Ceramic Store)
You can do some interesting things by using tape as a resist. You can make straight or wavy lines, and geometric shapes. Here are some ideas.
About the tape:
1. Masking tape is the most basic option, and while it has some disadvantages (it can absorb, it can tear while you’re pulling it up, and it doesn’t stretch), it can be a good place to start.
2. Blue painters tape is probably a little better. Electrical tape works well and stretches somewhat.
3. Another option is Chartpak which is a graphic artists tape and comes in various widths. (Do an internet search for sources.) Drafting tape is another option, as is auto pin striping.
4. Make sure the tape is stuck down well by burnishing the edges with a fingernail, edge of a spoon, or wood tool.
 5. Remember that the wider the tape, the harder it will be to get it to stretch evenly over a curved surface. But don’t stretch too much or the tape will try to pull lose.
About the technique:
1. If you can apply glaze with a sprayer, you will probably get the best results because you won’t get oozing under the edges of the tape. But other techniques can be used as well.
2. It usually helps to peel the tape off before the glaze is completely dry.
3. You can apply tape to bisque, then apply your underglaze or glaze. This is especially pleasing with Raku where the masked lines will turn black.
4.  For a more subtle look, you can pull the tape off and then cover the entire surface with a 2nd glaze. You will get a color variation where the resist was, creating a very interesting surface…
5. This subtle approach is especially good for people who are not detail oriented enough to do a fully geometric pattern, as it doesn’t need to be precise to look good…

6. You can also tear masking tape lengthwise to get a torn surface. (For larger areas try tearing paper towels or newspaper and applying when wet.)
7. There are many other substances that can be used for masking, such as wax. But tape has the advantage of being easily repositioned until you are happy with the pieces. Give it a try! Even if you don’t particularly like geometrics, you can create some fluid, organic designs. Or perhaps just a small patterned band at the top or bottom of your piece will bring it to life.

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