Guangdong Machinery processing plant Similar to gypsum mold casting, the mold used in ceramic mold casting is made of gypsum, plastic, wood, metal or rubber. The ceramic slurry is poured from the top of the mold. It hardens rapidly to the consistency of the rubber. It can peel off from the surface of the mold to form a new mold. Volatiles can be removed by flame combustion or low temperature baking. It is then baked in a 1000 degree oven to form a ceramic mold that can withstand the pouring of high-temperature metal. In addition, when the mold is still hot, the metal can be poured in. The tolerance can be controlled at 0.4%, the surface finish can be higher than 2-4 microns, the parting line tolerance can be increased by 0.3 mm, the wall thickness can be 1.25 mm, the weight can be from 60 g to several tons, and the draft angle is required to be 1 degree.
This process is expensive, but reduces the secondary machining operation. The typical parts produced by this process include stainless steel impeller, bronze parts, complex cutting tools, plastic molding tools. Steps:
The model is made of clay, wood or gypsum and must be covered with 2-3 thin layers of orange paint.
Step 1: first you have to study the solid, based on which you can make the mold for determining the parting line. Draw a line on the solid with a felt tip marker.
Step 2: place the entity on your workbench so that the parting line is parallel to your work surface to some extent. Extend the widest point outward one inch around the parting line before piling up the water-based molding clay.
Step 3: after the clay is piled up, that is, the smooth and leathery clay, cut into squares, as shown in the figure, use a soft brush to brush a layer of orange paint on the surface of the object and the top of the parting line respectively, and after 15-20 minutes, spray lightly with talc.
Step 4: apply a layer of release agent on the whole surface with a soft brush, dry the brush, and then brush away the excess release agent to make the object have a smooth surface and clay parting line.

Step 5: prepare the casting plate, wipe its front surface and edge with release agent, and assemble with C-clip as shown in the figure. Use a wooden tool to edge the intersection of the clay parting line and the inner surface of the plate as shown.
Step 6: prepare for casting. For the object size and parting line appearance volume around the model shown in the figure below. We're going to use the following proportions: a one gallon plastic can, weighing 11 / 2 lbs1 pottery plaster.
Step 7: soak gypsum mud for 3-5 minutes, and then mix with drilling fluid for about 5.5 minutes. The plaster should cover at least one inch above the model.
Step 8: after 20 minutes, separate the casting plate, scrape off the plaster at the top and tilt the edge slightly, grasp the other edge of the plaster mold and rotate it gently to loosen the clay from the workbench, as shown in the figure. Flip the mold so that the clay leaves the mold and the gypsum half mold.

Step 9: if the orange paint flows to the gypsum half mold, clean it with alcohol. Wash away all the clay particles on the surface of the mold, and now it's time to carve the key parts of the gypsum parting line. You can carve in a variety of ways - around the end of a big spatula, or a coin (nickel or string)
Step 10: Guangdong mechanical processing plant prepares the casting plate again, uses talc powder to remove the dust in the mold and parting line area, brushes the mold release agent as in step 4, assembles the plate with C-clip as in step 5, and repeats steps 6 and 7 to make the second part of the mold. Fix the stone mold for half an hour, remove the casting plate and scrape the upper part of the mold. Tilt the edges and corners.
Step 11: now ready to open the mold. Scrape off any plaster that may slip from the edge of the first half. Use a straight end screw driver or a wood edge screw driver to insert from the parting line. When the mold starts to separate, Guangdong machining plant will immediately turn the mold over and repeat this step. When the mold is loose, grasp the two half molds and separate them gently.
Step 12: the model is usually left in one of the semitypes. At this point, the accuracy of parting line, the material of the model and the degree of hardness of the material will determine the difficulty of removing the model from the semi model.

Step 13: if the model is made of clay, you can take it out gently with a screwdriver, but if you have to pry it up like a lever, put a flat wood under the screwdriver to ensure that the plaster mold will not break. If your model is made of metal, glass or ceramic, you may need to use other methods, such as air pressure or tapping around the model with a rubber hammer. In some cases, you may break the model by knocking it out. But remember, in this case, the mold is the main object, because a good and durable mold can produce 50-150 finished products repeatedly.
Step 14: with the two halves that clean up the other particles, we now decide where to carve the pouring hole. It can tilt the outer edges of the parting lines of the two halves and all the outer edges of the tilted mold in one half or in the two halves shown, so as to prevent the edges from being broken.

Step 15: at this point, check the root cuts that can be pruned in each half. Consider the weather and dry the mold for 4-5 days, so you get a mold.