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Available on the Downloads page
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Follow the video, step-by-step, to create this yourself. Don’t expect perfection the first pour, we did this dozens of times to get to this point. You’ll still make a few mistakes before getting it right, that is what DIY is about.
This design differs from the v2 drawing in that the plaster pouring cavity is formed by shelling (hollowing) the back side (top right). And this is designed for removal using a heat gun. This method has several advantages:
-No sketch offset or extrusion was needed to make the outer wall.
-Because the first 3D action is to extrude everything as one solid mass, corners of the outer 3D perimeter can be chamfered (but don’t do it so much that that there is insufficient thickness for the natches).
-The mug's geometry (offset inward by 0.8mm) is revolved, swept and bevelled by cutting into the block. Shelling to the same 0.8mm wall thickness, from the backside of the block, produces the cavity needed (top right).
-The last steps, after shelling, are chamfering the outside inner corner, cutting the holes for the natches and revolving the pouring spout (as a separate body).
-Our v3 natch system continues to work well with this (lower left).
-Printing artifacts are not a problem for prototype molds (visible op right). Production is asking me to enhance these (a freshly cast mug is shown lower right).
-The plaster mold is of stunning quality (the PLA 3D print was softened using a heat gun and carefully removed using needle-nose pliers).
-Slip cast mugs most often have poor-quality and oval lips. This one stays round because of the outward flare and the quality is better because the 3D printed pouring spout also acts as a cutting guide at the pre-removal stage.
-The PLA pouring spout is deep and absorbs no water. Thus, the slip level does not need to be topped up during casting, the slip surface stays flatter (not developing a bowl shape) so pour-out time can be accurately gauged by its slip level.
There are many casting body recipes that would work with this. DIY CAD skills will enable you to follow me into another exciting world: Low-cost 3D printing of the clay itself! Coming soon.
Buy me a coffee and we can talk