When making bone china cups, the larger the gap between the two plaster molds, the more prominent the stitching marks of the molds after firing. This is caused by the flattened clay particles being aligned parallel to the mold surface. The clay particles in the gap of the bone china cup mold protrude outward along with the gap. Although the imprints of mold stitching left on the surface of the green body will be polished off in the later trimming stage, because the clay particles in the mold gap of the bone china cup are arranged radially, this arrangement is relatively parallel to the arrangement on the plaster surface In terms of method, the shrinkage rate of the former is much smaller, so the mold splicing imprint on the bone china cup body will bulge again after firing.
Reasons and solutions for the splicing marks of custom molds for bone china cups
The shrinkage rate of the longitudinally arranged clay particles is relatively small, which will cause the trimmed mold joint imprint to bulge again after firing.
In some cases, different shrinkage rates can also lead to cracking at the mold seam.
In order to avoid such problems, sometimes it is advisable to dig a little deeper into the imprint of mold assembly on the green body when trimming the bone china cup, so that the surface of the green body will be fine after firing. is smoothed out. Often, however, damaged plaster casts are replaced, or broken seams are repaired. It is also a good idea to replace regular grout with grout that has less clay and more filler.
Post time: Jan-12-2023