The least expensive Shimpo banding wheel right now is $155. So I 3D printed my own as a test (this marvellous idea came from Crystal Bennett). The middle section is designed to fit inside the upper. To make it heavy, turn over the upper section, fill it to the brim with plaster, then press in the middle section until the plaster comes out of the holes (then weight it down till the plaster sets). The base is hollow, so it can be filled with plaster too. A standard 17x40x12mm roller bearing (available for $5 at the time of writing), it fits tightly into the recess in the middle section (and the base stem fits tightly inside of that). The resultant turntable turns super smoothly and rotates remarkably true. This drawing is parametric, so the dimensions can be adjusted easily. The size of the bearing that it will accommodate is also adjustable.

These glazes have not just crazed or shivered, they have pulled part of the body with them. What can generate forces great enough to create failures between glaze and body like this? Differential thermal expansion. Consider:
First, the glaze is thick. Very thick. Much too thick.
Second: A strong body:glaze interface zone has developed. That's good.
Third: The body is not firing to optimal strength (it appears porous). Not necessarily bad if the glaze fits.
What to do? Apply the glaze thinner, of course. But, testing should also be done to determine whether the glaze is under compression or tension. This could be done using the EBCT test.

The clay is Plainsman 3B.
Left: Without processing, other than grinding to 42 mesh (currently the finest we can grind on a practical scale), if fired toward zero porosity it burns like this (at cone 6, 8, 9, 10 and 10R bottom to top). Of course, this material is mainly used in non-vitreous bodies at cone 6, so these are not issues. The speckle and bloating are caused by impurity iron-bearing particles and others having an LOI (they decompose and produce gases that cause the bloats).
Right: The impurity particles make up a small percentage, they can be removed in our lab by sieving to produce a natural porcelain that fully vitrifies by cone 6 (the middle bar). Only about 5% of the material was removed to produce this amazing product (we call it MNP).
Imagine what could be done if we were able to mine raw material further east, where clay quality is much better!

Reactive glazes (melt-mobile, crystallizing or heavily pigmented) are the least suitable for food surfaces because they have the potential to leach metals. Liner glazing ware is an excellent way to deal with this problem. Not only does this approach improve functionality but it can be aesthetically pleasing and practical in production.

This liner is GA6-B, a pottery glaze recipe we promote with confidence. Not only is it less likely to be leaching metals but also less likely to craze - this assures water tightness on non-vitreous bodies and eliminates any potential for bacteria growth in the cracks (especially if the body has porosity). Unfortunately, glazes that leach are also likely to stain and cutlery mark - these add more reasons why they are most often unsuitable for food surfaces.

The straightness of the dividing line is affected by both the application technique and the degree to which the two glazes bleed into each other and run. Read and watch our liner glazing step-by-step and liner glazing video for details on how to do this - it is practical for any potter or hobbyist (or even in production). And tap/click the picture above for other examples of this.

CAD software and 3D printing are a potential revolution in vessel mold-making for ceramics (3D modelling is another topic). But there are two big problems: There is no way a potter, hobbyist or even small manufacturer can afford the typical software cost. While it is true most have free or low-cost trial or hobby versions, the strings attached are deal breakers. The second problem is the complexity of learning - that can be a bigger obstacle than cost.

Until the recent price increase Fusion 360 seemed to be exactly what was needed. A great way to on-board the CAD world, using the free version and its great learning resources and best-in-class user interface. It is new and modern, a YouTube star. It is fully parametric supporting constraints and a timeline. True, it can choke on more complex drawings on consumer computers, but we don’t need to do those. But, for commercial use, it costs $680/yr. But that is cheap compared to some others! Upon discovery of the capability, the cost might be doable for you.

Here are the ones you likely cannot afford (and maybe don't want):
-OnShape runs in your browser. It focuses on collaboration for teams. Free-version drawings are public but going private costs $1500/yr!
-Rhino is usable for CAD but is polygonal and targeted at modelling. It is not fully parametric and does not have a traditional timeline (however Rhino+Grasshopper is life-changing for geeks, both for CAD and modelling). $1000 to buy but upgrading is $500+.
-Solidworks is fully parametric with editable history. But it is old, the interface shows it. It is low cost for hobby use but for commercial use it is far out of reach for individuals ($2600/yr in 2025).

Some upcoming possibilities:
-FreeCAD is becoming more viable. It is parametric, has constraints and exports and imports popular formats (but with lots of issues). Its model tree is equivalent to the Fusion 360 timeline, but more clunky and depends on careful setting of constraints. The learning curve right now puts it out of practical reach of most. But a capital injection, like Blender got, is coming.
-Shapr 3D costs $299/yr, also works on iPad (which Fusion 360 does not), and uses the Parasolid engine like OnShape and SolidWorks. But it seems to be targeted at being intuitive for conceptual modeling and quick prototyping for drawings that are finalized in other products (limited support for accurate feature placement, constraints, parametrics and boolean operations).

This jigger mold-making method features a hybrid plaster form of the outside profile attached to a 3D-printed clamping baseplate. Clamp-on rails enable easy setup and extraction for mold production. Here are the steps:
-Download the drawing, edit the bowl profile and size (and the template) and then 3D-print the parts (typically using PLA filament). Print two rails.
-3D-print threaded anchors and attach them to the base plate.
-Center and clamp the spacer ring onto the flat side of the base plate.
-Set the model mold on a level surface, pour plaster into it (right to the rim), place the base plate (anchors down) onto it (being sure it seats down into the spacer ring to assure centering). The plaster should overflow up the air holes in the plate. Weigh it down and leave to set.
-Remove the mold (using heat gun if needed), finish the surface of the plaster (with a metal rib or 3D-print one with curves to match the contour) and soap it in preparation for pouring a working mold.
-Clamp the rails down to the base plate (using paper clamps), place the mold on a perfectly level surface and fill with plaster.
-Fit the template to your jigger arm (more than one cycle of editing the upper section and adjusting hole placement will likely be needed, so don't print it solid right away).
You now have a working jigger mold for use on a Giffin grip. Repeat the last step as many times as needed.

Pretty well all common traditional ceramic base glazes are made from less than a dozen elements (plus oxygen). Go to the full picture of this table and click or tap each of the oxides to learn more (on its page at digitalfire.com). When materials melt, they decompose, sourcing these elements in oxide form. The kiln builds the glaze from them, it does not care what material sources what oxide (assuming, of course, that all materials do melt or dissolve completely into the melt to release those oxides). Each of these oxides contributes specific properties to the glass. So, you can look at a formula and make a good prediction of the properties of the fired glaze. And know what specific oxide to increase or decrease to move a property in a given direction (e.g. melting behavior, hardness, durability, thermal expansion, color, gloss, crystallization). And know about how they interact (affecting each other). This is powerful. A lot of ceramic materials are available, hundreds - that is complicated when individual materials source multiple oxides. Viewing a glaze as a simple unity formula of ceramic oxides is just simpler.

Niko is trained as a product designer so the science and physics of clays and firing require lots of self-learning. She is "salvaging" red burning stoneware materials and hand building these large brick forms for firing between cone 7-8. Drying and firing such shapes without cracking is very demanding. For drying the blocks evenly she made a drying cabinet and put a hot fan to blow in warm air, maintaining an interior temperature of 45C (with high humidity). She puts the blocks on a piece of flat tile and covers them with a cloth to further assist in bringing away the moisture. She is able to fire the pieces on the third day after they have been in the drying tent for 2 days. The drying tent is an idea from the EKWC (European Ceramic Work Centre), these are often used for drying sculptures. Her firing schedule is 80C/hr to 140 with a 1-hour hold, 85C/hr to 650 with a 5-minute hold, 150C/hr to 1130 with a 30-minute hold, 60C/hr to 1230 with a 15-minute hold, 500C/hr to 1130 with a 30-minute hold, 83C/hr to 760.

At v7 I adopted a hybrid plaster/PLA approach, enabling a smooth working surface. This involved the use of threaded anchors to hold the back-plate to the model. v8 was the discovery of how to use tsplines in Fusion 360 to enable an oval neck on a round body. The big advances at this stage are the use of magnets and inset flanges (to hold it together) and discovery of how to project the lip geometry to make a perfect-fitting spare. As before, the 1.2mm thick parts print quickly.
The Backplate: It has holes for small bolts (to hold the threaded anchors), airholes, holes for natch clips, recesses to press in the magnets and an outer ridge to hold the rails in.
The Railing: Printed in two parts for easy removal. The bottom flanges have magnet insets. They are inward-facing, enabling a bigger size to fit on the bed of the 3D printer.
The Model Mold: The center piece will be filled with plaster to the brim (from the back) and the back-plate (with anchors) will be pressed down onto it. It has an inherently strong shape to produce a precise plaster model (that will be surface smoothed later).

Example of a glaze (G1916J) shivering on the rim of a mug. But the situation is not as it might appear. This glaze fits some bodies, crazes on others and shivers on yet others! This is a testament to how tricky it can be to fit glaze at low temperatures. But this is not a white glaze, it is a transparent over a white slip (or engobe). Alone on this red body this glaze appears to fit OK, but here it is exploiting the weaker body-engobe interface - this is where the release is taking place. This failure turned out to be a blessing, alerting us to the need to increase the expansion of the glaze a little to fit this body better (and enable its use with this engobe). This being said, the engobe likewise may be under too much compression, it may not contain enough silica.