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3D Design software is used to create dimensionally accurate objects by sketching 2D geometry and transforming it using tools to rotate, extrude, sweep, etc. The software generates the polygon surface.
Key phrases linking here: solid modelling, step format, 3d drawing, 3d design, sldprt, cad, f3d - Learn more
It is important to understand the difference between CAD and 3D modelling. CAD (e.g. SolidWorks, Fusion 360, Rhino, OnShape, etc.) is used in engineering, it is about editing a model, precisely dimensioning and constraining it. 3D modelling (Blender, Maya, ZBrush, Cinema 4D) is used in art and entertainment for sculpting organic shapes for use in animation. CAD drawings retain a history of each step and are usually parametric. CAD drawings are like fully functional "blueprints" with all the details intact. Potters, hobbyists and ceramic technicians are almost never mechanical engineers or special effects artists. That being said, CAD software is very useful in ceramics. Until now the price, computing power and educational resources needed for CAD were far beyond individuals, but that has completely changed. These packages are now mostly free to hobbyists or small businesses and there are tons of YouTube videos on using them.
The biggest hurdle to adopting 3D printing is choosing and learning to use a 3D CAD package. The processing power, multi-function mouse, connectivity and screen of a desktop computer are all needed for this (a desktop computer is generally needed to handle the 3D slicer software anyway). And 3D design software has decades of maturity on the desktop. Until now, Fusion 360 has been our choice, it seems ideal for individual designers and leaves me astonished every time I use it. OnShape seems to be the second option for independent technicians and hobbyists (because it offers a free edition) - the fact that it works in a browser brings a lot of potential to share a drawing for others to view and edit (they claim that multiple people can collaborate on the same drawing at the same time). If you are not easily intimidated, SolidWorks even has a free version for hobbyists now (and it operates in a browser like OnShape). Rhino for desktop deserves mention, it is popular in ceramic circles. It is often best to use the package your friends or teachers are using. It is vital to have a teacher (hire a consultant on Upwork if needed to guide you through a few design projects).
Some of what I just said is being challenged, 3D is moving to the iPad. As of 2022 Shapr is taking an industry-leading modelling engine, ParaSolid (the power behind SolidWorks), to the iPad. It also runs on desktop and enables working on the same design on both platforms. However, it is pricey given its capability compared to more mature options. FreeCAD is also developing into something that could be quite useful.
Common File Formats:
.DWG is primarily a 2D/3D geometry file format used by AutoCAD and similar software. It contains the final geometric data of the design, such as lines, arcs, surfaces, and solids. It does not store parametric relationships, feature trees, or a timeline of design changes.
.STEP (ISO 10303) is a standardized format for exchanging 3D CAD data between different software systems. It captures precise geometric and structural information about a model, including solids, surfaces, and assemblies. While STEP can include metadata and some constraints, it does not typically store the feature tree or parametric history from CAD software like SolidWorks or Fusion 360.
.F3D: Fusion 360 native format.
.SLDPRT and .SLDASM: SolidWorks native format.
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. Fusion 360 seems to offer a 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. If not, there is a second option: Move to Shapr 3D after learning. It costs $299/yr, also works on iPad (which Fusion 360 does not) and it is similar enough to make the transition easier. It is less powerful and lacks the training support, but the things it does do well are what is needed for mold making in ceramics. It uses the Parasolid engine like OnShape and SolidWorks (that royalty is probably what raises the cost). Here are the ones you 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 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). -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.
This is Fusion 360. The profile was drawn and various measurements parameterized (shown in the listbox on the lower right). That means the measurements were given names (e.g. body_diameter, thickness). This makes it possible to change aspects of the geometry of this shape by just editing the parameters. If you are experienced in 3D CAD you will be able to see this drawing is actually beginner-level, I have not fully defined and constrained it. For example, I cannot change the height or width and have it maintain the shape when it redraws (to do the z-axis value of the vertical center-points of the curves need to be defined as a percentage of the neck height, and the neck vs body height proportion also needs to be set). I should also have placed the center of the lip at the origin. Further, it does not need to be hollow, it should be a solid body enclosed by the desired profile.
The objective was to make a rubber master case mold for the production of working plaster molds. 3DP is a great solution. This drawing was done in Fusion 360.
1: A make a sketch of a box, around the handle, on the XY plane. Offset that outward by 1.2mm (my printer prints 0.4mm wide, three passes give good strength).
2: Extrude to create box 1: The base backward by 1mm and the sides forward by 20mm.
3: Use five sides of the box as cutting planes to slice it out of the mug.
At this point I could print this in PLA filament, pour plaster into and then use a hair drier to peel it off. But let’s make rubber molds instead.
4: Move the box-with-handle away from the mug. Pull the four sides out by 5mm to thicken them.
5 & 6: Create box 2 around the outside of it, as a new body, 1.2mm wider and taller, 1mm more frontward and 1mm less backward.
7: Use box 1 as a cutter to remove material from box 2 and then pull the outer 1.2mm sides 5mm backward.
8: Shell out the back side to 1.2 wall thickness and make two 9.4mm holes (to accommodate natch clips).
To make side 2 mirror-image a new body using the front or back as the reflexion plane. The back side is then filled with PMC-746 rubber to make the block mold. Plaster is poured into that to make each working mold.
You may already know that I am very excited about the potential of 3D printing for creating aids to making pottery. I glue four of these together to create a cookie cutter for producing slab-built mugs. For different sizes of mugs I need cutters with different geometries. This is quarter-cutter and it has been drawn "parametrically" using Fusion 360. That means that certain aspects of its geometry (two lengths and one angle) can be adjusted by simply changing the parameters (in the Parameters dialog). The drawing then adjusts automatically. It is magic! Other aspects are fixed (e.g. the right-angle, the pucker-preventing hole cutouts, the height, and thickness). Parametric design is revolutionary, it fits my try-it-adjust-it-try-it-again way of working. And, I can label these printed quarters according to the size, in this case 45-25-108.
This is an 85-year-old drawing downloaded from medalta.org. Medalta Potteries manufactured crocks, on a large scale, from the 1920s on. In this example, I imported the drawing as a canvas in Fusion 360, positioning it so the center of the knob was at the origin point. I traced the lid outline to create a sketch and then revolved that to create the 3D lid. This is part of a project to enable a potter to make lids to fit the old crocks.
Made from 1/2" x 3" flat steel, this frame is heavy and very strong and solid. The two larger 3.5" long bolts are custom-made from 5/8in-11 threaded rod, they have a 45-degree cone tip and locking nuts. The small vertical stopper-bolt is made from 3/8" rod. It is 2" long with 1" dia washer welded on top and a locking nut. The small bolt setting determines the bottom point of arm travel. The pivot sockets on the jigger arm are 1" long and made from 1" steel rod, each has the 45-degree recess machined into it. The arm can be moved left or right and its tension set by adjusting the two larger bolts. The weighted collar on the back of the arm employs two pieces of 1" thick flat steel, it is heavy (important for convenience-of-operation). The triangular notch enables the arm to be lifted higher. The weight colar needs some sort of set screw to hold it in place. A number of corners need to be rounded or rubber-padded for safety reasons. If you would like this 3D file in Fusion 360 and STEP formats, it is available in the Files manager in your Insight-live.com account (click the link below to go straight there).
This is the most complex shape known that can fit together organically. It was just discovered by mathematicians in 2023. It is easy to cookie-cut these out of clay (notice the cutter I made at the top). Placing the tiles is tricky because it is only logical to seek a pattern, but that does not work. Starting with a center tile and moving outward in a spiral around it seems to be the best way. Mathematicians are seeking to prove that placement can grow infinitely without ever repeating a pattern. Making the cookie cutter in Fusion 360 was easier than expected because the shape is built from the pie-slices that result from cutting a regular hexagon into six pieces midway across the straight sides. Because of the complexity of the shape I have found that it is best to print multiple cutters (I can do eight at a time), and stamp the shapes without using stretch wrap (letting them dry overnight in the cutters). The randomness seems confirmed in that when I piece together a few dozen tiles it is very difficult to do a count (because they are not in rows). In addition, to piece together 28 tiles requires turning eleven of them over - if there was a pattern I would expect to turn over exactly half of them. One issue: To create a setting with straight sides it appears I will need a dozen shapes.
This is for making test bars of slip casting clays bodies for use in the SHAB test (to measure drying shrinkage, firing shrinkage and fired porosity). I designed it in Fusion 360 and 3D printed the light-duty rails and case mold. I poured plaster into that to make the two plaster working mold halves (top right). The funnels provide a reservoir so the bars be cast solid. This mold can produce a set of three bars in less than an hour.
Shown here are Creality Slicer, Prusa Slicer and Simplify 3D. Each of these can import STL, OBJ and 3MF files. Each permits resizing, rotating, reflecting and duplicating individual items and can efficiently place and space multiple items and groups. Each saves or exports as 3MF files. On the right is the Fusion 360 print dialog where I can choose which slicer and which format to send.
OBJ files were introduced in 1980 for visual rendering (e.g. animation, gaming, special effects). Files store surface geometry as interconnected triangles and define surface textures, materials and colors. These features were overkill for early 3D printers.
STL (Stereolithography) files were developed in 1987 by 3D Systems specifically for CAD and 3D printing, having a single focus on geometry. They were simple and computationally efficient (and also unitless like OBJ, assuming mm). STLs permitted only one object. They dominated early 3D printing processes (FDM, SLA, SLS), where color or texture was irrelevant and provided a simple standard for industry growth. However, modern printers can now do color, texture and multi-material, thus...
3MF (3D Manufacturing Format) files were introduced in 2015 specifically for more advanced 3D printing. To OBJ they add object orientation, units, printing instructions and meta information. Objects in 3MF files can be manipulated separately in the slicer.
All three formats are generated by modern CAD software (for handoff to a slicer app). 3MF is the preferred one.
![]() The Prusa Slicer generates G-Code for 3D-printing |
![]() Make your own pyrometric cones? Why not! |
![]() Draw a triangular plate press mold in Fusion 360 |
Glossary |
3D Slicer
3D printing is very important in ceramics, hobby and industry. A slicer is software that slices up an STL file 3D model and runs the printer to lay down each layer. |
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Glossary |
3D-Printing
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. |
Glossary |
3D Printer
Standard 3D printers (not clay 3D printers) are incredibly useful in ceramic production and design, bringing difficult processes within reach of potters and hobbyists. |
Glossary |
3D Modeling
3D surface modelling tools enable the creation of objects by starting with a basic shape having polygon surfaces and then subdividing, pushing and pulling the quadrilateral or triangle polygon meshes to form shapes. |
URLs |
https://www.omnicalculator.com/math/right-triangle-side-angle
Right triangle calculator Useful to calculate angles and lengths when drawing 3D geometry from a model. |
URLs |
https://fablab.aalto.fi/
Fab Academy is a hands-on rapid prototyping course. Participants learn a true full stack of skills to be able to create high quality proof-of-concept prototypes. |
Projects |
Beer Bottle Master Mold via 3D Printing
A project that took several years of failures and blind allies and is finally coming together - so much simpler than expected! |
Projects |
Cookie Cutting clay with 3D printed cutters
We are finding more and more applications for this simple process of cookie-cutting shapes in ceramics. You won't believe whats possible and how easy it is to get started. |
Projects |
A cereal bowl jigger mold made using 3D printing
A new way to 3D-print your way to making jigger molds and templates. The molds are encased in a 3D printed shell that makes them fit perfectly into the cuphead. And the template is precise and very effectivwe. |
Projects |
Medalta Ball Pitcher Slip Casting Mold via 3D Printing
A project to make a reproduction of a Medalta Potteries piece that was done during the 1940s. This is the smallest of the three sizes they made. |
Projects |
Coffee Mug Slip Casting Mold via 3D Printing
A potter can now use AI, 3D CAD, 3D printing and custom clay bodies to slip-cast beautiful quality stoneware pottery mugs. It is efficient and practical. |
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