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Weighing things is an essential part of DIY ceramics. Examples are the batching of glaze recipes, porcelain and stoneware clay bodies, engobes, underglazes, slips, casting slips. Weighing out the kaolin, ball clay, feldspar, silica, frit, etc requires a scale. Other examples include mixing slurries or plaster batches that require a specific water:powder ratio. For 3D printing a common need is weighing the amount of water a mold will hold as a way to measure its cc volume. Scales like this offer 0.1g accuracy and can handle 6000g (older ones could only handle 2000g). This enables counterbalancing stainless or even glass containers. These scales were very expensive in the past, but not anymore.
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In glazes, engobes, underglazes, etc it is common to need tiny percentages of materials (e.g. pigments, anti-microbials, gums, gelling agents, flocculant, speaking agents). A scale like this enables accurately weighing to within one one-hundredth of a gram! These were prohibitively expensive in the past, but not any more. Newer 0.01g scales have a higher capacity also - this one can weigh 600g (older ones were only 100g). This higher capacity enables more flexibility in choosing a tray (shown are the ones you can buy). You can also 3D print light-weight trays.
This picture has its own page with more detail, click here to see it.
Because of the ease of 3D printing case molds at home I can now pour plaster in them also. Of course, I am not in production, this is about creating prototype molds. This technique makes it possible to be precise in the amount of plaster used, so there is almost no waste. My tools are simply a good propeller mixer, and a scale and a 3-D printer (and a cooperative wife). Here is my procedure:
-Counterbalance a plastic container.
-Fill the mold with water and pour into the plastic container to get the weight in grams (and thus cc's).
-Plug that weight into https://plaster.glazy.org, set it to use centimenters and get the USG recommended weights for plastic and water.
-Put that amount of water in the flexible plastic container and tare it.
-Dump in the plaster needed (no need to sprinkle it, I have a good mixer).
-Set the timer for 4 minutes and let it soak.
-Put it under the mixer (at an angle as shown), set the speed to create a whirlpool just shy of pulling in any air (thus avoiding adding bubbles). Mix for 4 minutes and then pour it into the molds.
-Clean the mixer blade and shaft in a container of water (and throw that away outside). Let the plaster harden in the plastic container (it breaks away cleanly later).
-Let it set overnight and use a heat gun and pliers to carefully remove the PLA from the plaster.
Buy me a coffee and we can talk