Fired Glaze item that turned out bad
OOOOPS #2 – Glazed pieces This is the second in a series on things to do when you make mistakes that cannot be fixed. You’ve glazed a piece and the colors did not turn out. I mean REALLY bad. Example: you fired red with a non-compatible green. Well, if you’ve ever done this, you know what can happen – ICK! Or you fired a piece with too much glaze application and it ran off the piece (dripping on the shelf most likely) leaving bumps on the bottom so the item cannot sit properly, or you had a kiln misfire and the piece melted into a warped lump or mass. Maybe your piece cracked during firing or from thermal shock. You get the idea? 1. Before giving up on your glazed piece, check around and see if it can be fixed somehow. You would be surprised. Some mistakes can be remedied with reapplication of the glaze and/or re-firing your piece. 2. If you have a shop/studio that is open to the public, you might want to set-up a display showing mistakes and what NOT to do. A visual is always a much better lesson than just talking or reading about it. 3. You have a piece that the decal messed up. You can try to fire it off; but sometimes there is still a trace of the overglaze design left. Try applying mother of pearl or other luster over the item including the decaled area. It can create a pretty and elusive effect. 4. Wearing protective goggles, take the item and lay it between a folded towel and break it into pieces with a mallet. Break all the large pieces into smaller pieces. Be careful handling the pieces and the crumbs because they have shards of glaze (GLASS) edges and they are sharp. Pick out the larger pieces from about ½” to 2” and discard the rest. Be careful to not shake the towel – you do not want crumbs to fly where they will hurt someone or breathe in the dust particles. Find yourself a suitable piece of plain bisque, some plaster or other kind of grout and create a mosaic with the broken pieces. Odd shapes and angled pieces and even designs like flowers or pieces of wings can be used as focal points in your design. Mosaics don’t have to have all flat pieces. Use a stilt stone or other file to sand away edges to make shapes fit together better. You can also bag these pieces and sell them to others who want to try their hand at doing mosaics. 5. Keep a box or bin handy to hold all the mistakes. I called mine a stress box. On days that I, or my kids, or my customers felt like screaming, we would go outside to a designated are and throw the pieces against the wall. It felt so good, no one minded having to clean up after. They make good skeet targets too. 6. You don’t like the color. Consider applying some kind of over glaze. It is amazing the effects you can get from this simple ‘fix’. 7. Use a china paint that is a compatible color and darker than your item and sponge the color onto your piece and fire it. 8. Buy a can of texturize paint from your neighborhood Home Depot, Lowe’s or other paint store and spray your piece. The color may eventually chip off, but it can look nice for quite some time with a little care. They have some great stone like sprays. 9. Try taking that ‘ugly’ piece and do a raku firing with it. You will get some amazing effects. Have you got any creative ideas you would care to share? Step eight: Compute how much plaster you need for the mold by determining the cubic measurement (volume) inside the box and how deep you want the mold to be (Height X Width X Length). The ratio of plaster to water is 70 parts water to 100 parts plaster, or 7:10. This equates to 1 part water to 1.34 parts plaster. Using a hypothetical size for your mold of 4” wide X 6” long X 2” high, you would compute your proportions like this: 4”X6”x2” = 48 cubic inches = .83 quarts = 26.56 ounces US = 3.32 cups volume = 1.66 pounds water or .753 kg (a quart of water weighs 2 pounds US) 1.66 pounds water x 1.34 = 2.25 pounds plaster, or .753 kg water x 1.34 = 1.02 kg plaster A more accurate and precise measuring can be obtained by using metric measures. Step nine: Now it is time to mix your plaster. Once you add water, there is no turning back. How you mix your plaster is your most important step and will determine the strength and durability of your mold. Measure your plaster and set aside. Temperature of your water is also important. Measure the determined amount of warm water (about 90 degrees) into the mixing bucket. Slowly sift/shake the measured plaster into the water by hands full and allow it to sink. Soak for about 3 or 4 minutes so that it can fully absorb water, and then begin mixing with your hand (for small batches – 5 to 10 pounds), until it forms a nice silky glove on your hand. It will feel somewhat like warm pudding. This will take about 10-12 minutes. Care should be given that you DO NOT OVERMIX. As it mixes, it will get warmer to touch. You don’t want the plaster too thin or it will not mature appropriately and it can splash and cause bubbles as you pour it. If it is too thick, it can cause air pockets and it will not fill in the details. ALWAYS add plaster to water, NEVER water to plaster. For larger production, it is important that mixing be consistent and it is advised to use motorized mixing. Size of motor would depend upon your production level. Step ten: Once you have the plaster ready, pour a steady stream into the box, aiming for the corner or side and letting it fill and flow freely over the item. Fill the box to the appropriate level needed. Step eleven: Immediately clean the bucket before the plaster hardens.. Let the mold set until completely firm. Step twelve: When the mold has hardened enough to hold its shape and be handled, remove the wedges to loosen the rope and remove it. Knock the sides away from the mold and remove the mold from the bottom. Clean away all the clay. You can re-use this if you save it in an air tight container. Using the knife, scrape all exterior edges of your new mold, removing the sharpness. There you have it. Let the mold dry thoroughly before you try to use it. NOTE: DO NOT purchase large quantities of plaster unless you plan on using it over a short space of time. Find a source who will sell it in smaller quantities equal to your projected usage. Once it is open and has access to air, it will degrade over a very short period of time.
*DISCLAIMER: When making molds of items, be aware of copyright and trademark infringement. There are laws and penalties for copying others creations.