Working Through a Potter's Checklist System
I have been running a small studio for about twelve years now, and somewhere around year three I realized I was losing more pieces to preventable mistakes than I cared to admit. Not the dramatic kind, either. The little things. A crack I could have caught if I had just checked the wall thickness at the right moment. A glaze that looked fine in the bucket but crawled into spiderwebs because I had not fired it cold enough on the first hold. It added up. What followed was basically a personal Pottery Checklist Top 10 system that kept me from repeating the same errors. I am not claiming it is perfect. It is not. But it has saved me roughly forty percent of my waste rate, and it takes me about ten minutes to run through it on a busy day. Here is what ended up on it, and why each item matters in practice.
Pottery Checklist Top 10
1. Clay Consistency and Wedging Marks
Before you even put the clay on the wheel, check that it is evenly wedged. I used to skip this when I was behind on orders, and I paid for it. Air pockets are invisible until they are not. The telltale sign is a spiral pattern on the interior of a thrown vessel after firing — it means air got trapped during centering. Roll a small test ball and press your thumb into it. If the texture looks grainy or uneven, re-wedge. This should take two to three minutes per batch. The clay needs to be leather-hard before any trimming or handle attachment, but not so dry that it cracks under its own weight. I learned this the hard way when a set of mugs warped in the kiln because I had assembled them while the bodies were still too wet. The fix is simple: wait until the piece no longer leaves a fingerprint when you press it lightly, but it still feels cool to the touch. That is usually six to eight hours in a typical studio with decent ventilation. Use a wire tool or calipers to check that your walls are even. I once fired a bowl where the base was twice as thick as the rim. It cracked on the first cooling cycle because the thicker section retained heat longer. Aim for consistent walls between three and five millimeters for most tableware. A quick check with a needle tool every few throws will save you a whole batch.
Make sure each piece is fully dipped or brushed, especially the foot rings. I have lost entire runs to glaze crawling because someone forgot to wipe the bottom before loading the kiln. The excess glaze pools under the piece and fuses it to the shelf. Wipe the foot with a damp sponge, then check that the glaze line is even all the way around. This takes about thirty seconds per piece. Stack your kiln so that heat can circulate freely. I used to pack it tight to get more pieces in per firing, and I ended up with variable results that made quality control a nightmare. Leave at least two centimeters between pieces, and do not stack tall thin forms next to each other unless you shelve them separately. A well-loaded kiln fires more consistently than a packed one, even if you run fewer pieces. Double-check your pyrometric cone placement and that your kiln controller is reading correctly. I had one bad firing where the thermocouple had drifted, and the kiln ran twenty degrees too hot. The glazes melted into puddles and the shelves warped. Check your calibration at least once a year, and always place a witness cone near the center of the load where heat distribution is most even.
Get the Full Details
Cooling too fast causes thermal shock, especially with thick pieces or those with heavy glaze layers. I once cracked a set of plates by closing the kiln lid immediately after the cycle ended. Let the kiln drop below four hundred degrees before you start any forced ventilation. If you are in a rush, crack the lid slightly and wait at least two hours before opening it fully. Patience here prevents callbacks. Run a visual and tactile inspection on every piece before it leaves the studio. Tap it lightly with a fingernail — a clear ring means it is sound, a dull thud indicates internal stress or micro-cracks. I stopped skipping this step after a customer returned a set of vases that had failed a year later because I had missed a hairline fracture at the base. Ten minutes of inspection saves far more than ten minutes of refund processing. Store finished ware in a stable environment away from direct temperature swings. I learned this when a batch of glazed bowls developed stress cracks after being left near a heating duct over winter. Keep your storage area between eighteen and twenty-two degrees Celsius with moderate humidity. Stack plates with felt separators, and do not stack more than five high unless the pieces are small and uniformly thick.
Keep a simple log of each firing: date, kiln load, glaze batch numbers, and any anomalies. I started doing this after I could no longer explain why a particular glaze looked different from one firing to the next. The answer was usually a new batch of raw material, not a process change. A notebook or spreadsheet with fifty entries takes less than an hour to set up and pays for itself the first time you need to replicate a successful result. I want to be clear about limitations. A checklist does not replace skill. It catches mistakes you already know how to avoid but might miss when you are tired or rushed. It also assumes you are working with standard stoneware or porcelain at cone six to ten. If you are doing low-fire majolica or raku, some of these items need adjustment. The kiln loading pattern for example, changes significantly when you are firing at cone 04 instead of cone 9. Another limitation is that checklists work best when everyone in the studio follows the same version. I had a helper who skipped the wall thickness check because she thought her eye was good enough. It was not. She cracked three mugs in a single firing. The solution was not better trust, it was a signed sheet at the end of each day confirming each step had been completed. That sounds bureaucratic, but it reduced our repeat errors to near zero.
If you are just starting out, do not try to implement all ten items at once. Pick the three that address your biggest waste category and build from there. For me, that was wall thickness, glaze coverage, and cooling rate. Those three alone cut my reject rate by about a third within the first month.
