The upper rim attachment, when done properly, is actually quite good. The edge of the rim piece naturally forms a ︿ shape. However, some colleagues insist on filing down the raised portion at the bottom of the rim piece. This approach is counterproductive: first, it wastes effort; second, the filing is unnecessary. It's truly thankless work. The fundamental reason is a lack of understanding that technical skill must be applied at critical points. Therefore, the rim effect must be as shown in the diagram above. To achieve this effect: first, do not file away the correct shape that naturally forms on the rim piece; second, the edge of the tool used to press the rim piece should be shaped as indicated by the dotted line. Using the correct method to produce rim pieces has two advantages: first, when attaching the rim piece, it's tight on the inside and loose on the outside, making it less prone to cracking; second, when attaching the rim piece, because the inner corner of the rim piece presses down on the clay coil, when you press the clay coil, it won't shrink inward. This is the key technical point. When engaging in creative work, innovation, or making master molds, one must consider the rationality of the production process and quality assurance. Currently, some products suffer from quality issues due to unreasonable innovations. For example, the raised false bottom of the "Han Ping" style, or the small "coffee pot" shaped varieties—expanding these to larger sizes is an unreasonable innovation. Facts have proven that not a single one of the large-sized teapots produced this way is round or properly level. The reason is that large sizes cannot be attached this way; they are built up by piling clay, which lacks structural integrity. The spout opening is weak or has insufficient flow...