Clay Times Back Issues Vol. 2 Issue 4 • May/June 1996 - Page 14

Mixing Your Own Clay to formulate your own clay can be rewarding in many ways. When you stock your raw materials on-site, mixing your own clay affords a steady supply of moist clay for production. You can mix as little or as much clay as necessary for a specific project. Several different clay body formulas can be mixed and stored until they are needed. Also, a wide variety of clay body formulas can be mixed and tested in a relatively short time. Yet mixing your own clay is labor intensive. The most expensive part of making ceramic objects is the labor involved in producing the work. And every hour spent ordering, stacking and mixing clay is an hour not spent making pots. Think of mixing your own clay as starting a clay mixing business (with yourself as the customer) to supply your other business (the production of ceramic objects). B LU E B I R D Manufacturing, Inc. Post Office Box 2307 Fort Collins, CO 80522-2307 Powerstar I Vacuum Pugmill Optional Stand Tel.: (970) 484-3243 Fax: (970) 493-1408 Internet e-mail: 14 ▼ continued from page 11 Once the decision is made to mix clay, there will be two businesses to finance, manage, and maintain. At some point, it will be counter-productive to keep moving backward in the production cycle, considering the additional expense that must be added to the original cost of producing ceramic objects. Purchasing clay mixing machinery is expensive, and one should also consider the cost of equipment maintenance and repair. Buying and maintaining a pug mill and clay mixing machine can use up money that could be appropriated to other business expenses which might return a greater profit. Then again, recycling and re-use of your clay can save you money, too...and the purchase of dry ingredients in bulk also offers considerable savings. If you choose to buy clay mixing equipment, note that the purchase of a smaller machine than necessary will result in slower clay production and possibly higher maintenance costs due to inadequate power. If you buy a machine that’s too large, it will consume space and greater amounts of capital, and result in unused production capacity. Before you buy, it’s wise to research as many different clay mixers and pug mills as possible, and try to speak with persons who actively use the equipment to determine the best machine for your individual production needs. Do you have adequate space for mixing equipment and for storing dry clay ingredients? Ordering of dry clays should be done in a way that ensures a steady supply to avoid delays in clay mixing operations. The greater the quantity of dry materials purchased, the lower the cost per pound. Clay mixing areas need to be located away from your regular workspace, as the dust generated is extremely harmful to inhale. Yet the closer you locate the mixing area to your workspace, the more time and trouble you’ll save by moving clay as little as possible. Buying Pre-mixed Clay When you pick up the phone to order conveniently packaged, moist clay, you let the professionals take charge of what they do best: the blending of clays under accurate, quality control conditions. Many suppliers will give free samples of stock clay to help you settle on a formulation that’s right for your individual needs. The clay manufacturer should be knowledgeable about the current “track record” of every type of clay, and take care to identify irregular shipments from the mines. If pre-mixed clay is an option, select a clay supplier with a good reputation for quality and customer service. Once you’ve received your premixed clay, keep a record of the batch code number listed on each box you use, in case you experience trouble with the clay during forming or firing. If possible, mark each of your pots with a code that corresponds to the supplier’s code. In this way, a bad batch of clay can be isolated and traced back to the ceramics supplier’s coded batch of clay. If other potters had problems with that particular batch of clay, the supplier should have a record and you’ll have a better chance of isolating the problem and obtaining a replacement batch of clay. ■ Author Jeff Zamek operates a ceramics consulting service. He may be reached at: 6 Glendale Woods Drive; Southampton, MA 01073, (413) 5277337. Tune in to future issues of Clay Times for features on purchasing pug mills and clay mixers, and how to perform the clay mixing process. —Ed.