|Monthly Tech-Tip |
It was glued down using the casting slip itself (it stuck in seconds). About ten minutes after draining a fettling knife was run around the inside, then it detached easily. The overhung lip produced imparts structural strength that resists warping, for drying and firing, to the thin walled piece. This spout has advantages over the traditional "spare" built in to the upper part of a mold. It enables a one-piece mold. The lip can be more overhung. Draining is cleaner and easier. Molds are lighter. Extraction can be done sooner and it is easier. The spout does not absorb so there is less scrap. The degree of overhang is adjustable by simply printing new spouts.
This is another example of the flexibility potters have compared to manufacturers. These 3D-printed gizmos are stuck onto this beer bottle mold using the casting slip. Dipping their flat surfaces and attaching them takes seconds. Another feature of this mold for potters only: There are no notches (the halves were poured into disposable 3D printed PLA masters - and mate perfectly). Using the rubber band to hold them together was not ideal because realignment of the halves damages the square inside edges. By using this method the mold halves can be aligned accurately. The 3D printed pouring spout is likewise attached using the slip (it also helps hold the mold halves together).
Standard 3D printing technology (not printing with clay itself) is very useful to potters and ceramic industry in making objects that assist and enable production.
Warping happens during the firing of ceramic ware when there is a high degree of vitrification and inadequate measures are taken during forming and firing to prevent it. Unexpected warping often happens with unstable shapes and over firing.
A method of forming ceramics where a deflocculated (low water content) slurry is poured into absorbent plaster molds, forming a layer against mold walls, then poured out.