Just in Time: Clocks!

Also published at Shapeways Magazine
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Need a last-minute gift for a special person on your holiday list?  You can create a unique, custom 3D-printed clock with just a little bit of design knowledge and an inexpensive battery-powered clock kit like this $8 Youngtown Silent Clock Mechanism with Small Hands:

You’ve got from now to the second week of December to get a 3D design together, if you want to order a 3D print before the Shapeways Material Cut-Off Dates for the holidays. In this post we’ll show you how you can create a custom 3D-printable clock face with three different software programs. Don’t have time for that? Skip to the end to see how you can customize a retro clock very quickly with our Sunburst Clock Maker.

Beginner: Tinkercad

Even if you’ve never created a 3D design before, it’s easy to get started with Tinkercad, a free in-browser 3D design tool with a simple drag-and-drop interface. To get started, sign up for a free account and check out the All3DP video Getting Started in Tinkercad: A Tutorial for Complete Beginners. Once you know a few Tinkercad tricks, you can create complex designs from very simple combinations of shapes; throughout this post we’ll link to helpful YouTube videos to show you exactly what you need to know.

To make a simple clock in Tinkercad, we’ll start with a cylinder for the center face, and then create a couple of stretched-out rings with Rotated “Round Roof” shapes and Holes:

By using the “Control-D” duplication tool we can copy and rotate those rings in a pattern around the cylinder. After modifying the heights of each shape with the Ruler, we get a simple retro clock face design:

If you want to pick apart our Tinkercad design and see how it works, just open this Quick Clock link and tinker for yourself! Add some Text for numbers, if you like, or design something new from scratch. When you’re ready to download your design for 3D printing, click the “Export” button and then choose “Export as STL”.

Intermediate: Fusion 360

To make a fancier custom clock, try Autodesk’s Fusion 360 3D software, which is free for students, educators, and hobbyists. There’s a steeper learning curve to get started in Fusion 360 than there is with Tinkercad, but there are plenty of video tutorials online to help you learn. Some of the best are the Fusion 360 tutorials by Maker’s Muse. We’ll link to relevant video tutorials throughout this section so that you can learn just what you need. Fusion 360 is a very powerful program with a lot of features and tools, but you only need to know how to use a few of those tools to make a simple clock!

For example, if you know how to create a Sketch, add Constraints, and use a Circular Pattern, then you have all the tools you need to create a 2D shape for a clock face design in Fusion 360. To create the example below we started a Sketch, added a Circle at the origin, then formed spoke shapes with Lines. We kept the shapes symmetric by using Constraints, and rotated them in a Pattern around the origin. In the screenshot below we are in the process of duplicating and rotating the thinnest spoke to create twelve copies of it around the center circle:

Most models in Fusion 360 start from a two-dimensional Sketch like the one above. Once you’re done with your Sketch you can Extrude to give it some three-dimensional depth, and then Fillet the edges to make them rounded and professional-looking:

To download your model for 3D printing, right-click on the gray name of your model in the Browser menu (if you haven’t saved your Fusion 360 design yet, then the name of the model will be “(Untitled)”, as it is in the screenshot above). Select “Save as STL”, click “OK” in the new window that pops up, and save the STL file to your computer.

Advanced: Make ALL THE CLOCKS

Feeling more ambitious? With some parametric design you can write OpenSCAD code to generate billions of clocks, each from a random seed. For example, consider the many types of retro-styled “Sunburst” or “Starburst” clocks shown in this Google Image search:

Clocks like these were inspired by the modernist-style work of industrial designer George Nelson, who made many variations of such clocks in the 1950s. There are some common design features that are shared by most of these clocks: geometrically-shaped spokes, a star/sunburst pattern, a circular inside for the hands… Here’s what our first notes looked like when we started thinking about the typical parts and designs for Sunburst Clocks, and some of our early test prints:

OpenSCAD is a free code-based design software that works on any platform. With just a little bit of coding knowledge you can write simple code to describe a library of geometric spoke shapes, and then options for rotating those shapes around a central circle. There are literally billions of configurations; here are just a few:

If you want to learn more about OpenSCAD, check out our beginner’s video tutorial PolyBowls – A simple OpenSCAD code walkthrough and intro document Hello OpenSCAD. The “Hello” document has a link to sample code you can inspect and modify; if you want to play around with the code that made the clocks in the rotating image above, you can download it from our Thingiverse page.

The Easy Way Out: Customize a Sunburst Clock

But… you may be thinking… there is NO TIME FOR THIS!! The holidays are coming fast, and you don’t have time to learn how to write parametric OpenSCAD code right now? No problem, just use our Customzier to design your own retro clock! We’ve made our design free on Thingiverse so you can create unique and interesting Sunburst Clocks in just a few seconds. Just go to the design on Thingiverse and click the “Open in Customizer” button to get started (you’ll have to sign up for a free Thingiverse/MakerBot account to open the design in Customizer):

The Customizer version of the Sunburst Clock design lets you create new clocks just by clicking in the Random Seed slider and selecting design options from drop-down menus. You can also set the overall shape and size of your clock, and control the center hole and backing to match your clock kit:

Once you have the clock you want, click the “Create Thing” button and download the STL file from your list of Things within Thingiverse. Here is a design we made with the Customizer and had printed at Shapeways in White Versatile Plastic for less than $30 (it’s the “Cordelia” design), together with the clock mechanism we’ll use to assemble the final clock:

After assembly, the clock looks like this:

And here’s an “action” shot on the wall:

Light Speed: Order an Existing Design

If you’re really down to the wire and don’t have time to create or customize your own design, then quickly head over to the Shapeways Marketplace for a huge selection of unique 3D printed gifts that you can order right away. If it’s before the December 13 cutoff date for medium-sized White Versatile Plastic at Shapeways, then you still have time to order, with next-day shipping and priority manufacturing, one of our best twelve pre-made retro clock designs from the geekhaus shop, like the Velma:

Happy making, and happy holidays!

 

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3D Printing Strong and Sturdy Models

Also published at Shapeways Magazine
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Sometimes a digital 3D design looks great in your software, but just can’t make it in reality. Here in the real world, a 3D model can only be so thin or fragile; models with very skinny wires or delicate parts might break after printing, or worse, not be able to 3D print at all. In this post, we’ll examine how auto-checks, human checks, and prototyping can help you design models that print successfully and are sturdy enough to handle repeated use or handling.

Auto-Checks

Shapeways provides guidelines and auto-checks to ensure that your uploaded models are printable in each material. For example, models created at Shapeways in Versatile Plastic are 3D printed in a durable nylon material in large batches using an industrial Selective Laser Sintering (SLS) printer. Versatile plastic has an intense post production process that includes extraction from powder and other models, cleaning and polishing, and even dying in different colors. Thin or narrow models can be easily broken or separated during post production. You can refer to the Design Guidelines for Versatile Plastic to determine how thin you can make the wires in your model. Here’s what those guidelines say about two success parameters, wall thickness and wire thickness:

In the guidelines above, “walls” are flat surfaces in your model and “wires” are more like strands. Notice that the recommended minimum for supported wires (those that connect to your model nearby on both ends) is 0.8mm. Processed models are put through a polisher, and Premium models are polished even more, so their minimum is higher: 0.9mm. Finally, the minimum for unsupported wires (which don’t inherit as much stability from the rest of the model) is even larger, at 1.0mm.

After you upload your model, Shapeways will perform a series of auto-checks to measure the thickness of walls and wires, among other things. If you click on “View 3D Tools” (or “View Issues”, if your uploaded model failed any checks) from within any Material view of your model, Shapeways will show you the results of these auto-checks. Here’s what that looked like for an early demo version of our Deltoidal Icositetrahedron model:

Although this model passed the Wire Thickness check, it fails the Wall Thickness check. The flattened nodes at the vertices, and even some of the long wires, are considered “walls” here, and they aren’t thick enough to get over the 0.7mm minimum thickness requirement.

Checking and Fixing Thickness Issues

You can check the thickness of your model in whatever design software you used to create it. Or, another easy way to determine the minimum thicknesses of your design is to import your model to Meshmixer and use the Thickness tool in the Analysis menu. You can then use Meshmixer to make your design thicker, if needed, by selecting the model and then using Edit > Extrude (using the Normal Direction) or Edit > Offset to expand your model outwards or inwards. To thicken only selected parts of your model, you can take the more targeted approach described in our previous article Tutorial Tuesday 50: Using Meshmixer to Make 3D Models Thick Enough to 3D Print.

Prototyping

Even if your model passes printability checks, it’s worth printing a demo model to make sure that everything is okay. Sometimes, weak geometry can’t be determined until a model is actually printed and in your hand. Even if the print comes out successfully, it may be too delicate to hold up to its intended use. After our example model failed printability checks, we redesigned it so that it would just barely pass the checks and print successfully. It was a beautiful model, but it wasn’t long before it broke and warped:

I guess the moral of this story is: For best results, don’t try to just *barely* meet the print requirements; rather, make sure you are safely above them.

It’s worth pointing out that the size of the model itself matters as much as the thickness; the two go hand-in-hand. In the image above, the smaller model has the same wire thickness but is actually quite sturdy. The larger model is weaker because the wires are longer and have to hold up to greater stress when the model is handled. This means when prototyping, you can’t always get an accurate impression of the strength of your model by shrinking your model down, or designing a smaller version. Think about it this way: a wireframe model the size of your head will need a larger wire thickness than a model the size of your pinky!

In the end, we decided to thicken up our Deltoidal Icositetrahedron model significantly. The final version looks like the blue model on the right in the image below. It’s much stronger, and the cost of printing was only increased by a few dollars.

Human Checks

Sometimes models pass the online checks at Shapeways, but then fail a secondary check when they are actually ordered for printing. That’s because actual human beings at Shapeways check your model manually while they prepare it for 3D printing. They check for things that require a lot more expertise than the automatic computer checks, like how large your model is, how the different pieces of it fit together, and a lot of things that you or I might not think of. If they notice a problem then they will email you, and try to suggest ways that you can modify your model to increase the likelihood that it will print successfully.

Keep in mind that the printing engineers at Shapeways want to make sure that your model can print correctly not just once, but over and over. A model that passes the auto-checks and listed guidelines may have weak areas that may not break on the first print, but are likely to break the second or third time. This means that even if your print comes out well in a “Print it Anyway” situation, it still might not be stable enough to offer as an item in the Marketplace. Variations in print stability can arise from small differences in the printing and finishing process, like how the models are packed or oriented in the machines, or how it interacts with other models in the polisher.

As an example, consider our Hoop Knot Earring:

According to the Design Guidelines for Silver, we needed to make the wires at least 1mm in diameter. However, it’s best to exceed that significantly; consider that Silver models from Shapeways are 3D printed in wax, cast in Silver using lost wax casting, and then finished and polished. All of those procedures could damage a model with weak geometry. When we uploaded our Hoop Knot Earring for printing, it passed all of the auto-checks. But when we tried to order a print of it in Silver, the kind and knowledgeable human engineers at Shapeways said that the geometry of our model was too weak. They suggested adding connectors and even emailed me this helpful illustration:

Of course, in this case I couldn’t add connectors since that would have ruined the design; instead I had to make the wires thicker to give the model more stability. That resulted in the print shown below on the right. Later I tried to make a larger version, shown on the left, but an interesting thing happened; since the wires had to travel further, they were more prone to bending and becoming misshapen when I opened and closed the earring. Even though the larger model had thicker wires, in the end it didn’t work as well as a functional item.

In the end, you’ll have to use a combination of your own design analysis, automatic printability checks, manual printability checks, and physical prototyping to successfully print delicate or geometrically complex models. If you’ve got your own tips and tricks that help you through this process, let us know!

 

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Is your 3D model a mess? Make it printable!

Also published at Shapeways Magazine
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What do you do when your 3D model is broken? I mean really broken, like “can’t even upload it” broken, or “half of my triangles are disappearing” broken? In this post we’ll talk about what to do when your usual mesh-repairing strategies fail and you need to bring out the big guns.

Let’s do this by example. So that we can follow exactly what’s going wrong, we’ll create a bad mesh by modifying an existing 3D model, my Deltoidal Hexecontahedron Catalan Bracelet:

We’re going to turn this into a tealight ring and add some solid faces to the wireframe to create a partially-enclosed look. The screenshot below shows what it looked like when I did this in TopMod; I added the closed triangle faces, and everything seems fine:

Nice! But when we try to upload to Shapeways, we get this error message:

First line of defense: Meshmixer

Meshmixer is a great first tool for modifying 3D meshes; for an in-depth example see our previous article Tutorial Tuesday 50: Using Meshmixer to Make 3D Models Thick Enough to 3D Print. But, in this case, when we open our broken file in Meshmixer to see what’s going wrong, the faces don’t load in. Although Meshmixer knows something is wrong here, its Inspector cannot repair it:

Second line of defense: MeshLab

Another great mesh-manipulation tool is MeshLab; for a primer on making simple mesh fixes with MeshLab, check out our previous article Tutorial Tuesday 5: Quick Fixes With MeshLab. It’s more complicated than Meshmixer, but can often take care of bad geometry like reversed normals and non-manifold faces. However, when we try to open our broken file in MeshLab we get this error:

After opening the file and looking through some of the Cleaning & Repairing filters, we see that there are some non-manifold faces:

The problem lies with where the new faces intersect. When we added those new triangles, we created some bad geometry where the pairs of coincident faces meet.  Alas, although MeshLab can identify these problems, it’s not able to actually fix them; usual MeshLab repair menu options such as “Remove Faces from Nonmanifold Edges” and “Remove T-Vertices by Edge Flip” are unsuccessful here.

The big guns: MakePrintable

If you have a Windows machine, you can try using the professional software Netfabb to repair this model. Netfabb is free for students, but for the rest of us it costs $30, per month. For professionals in industry this is probably reasonable, but for smaller businesses and hobbyists it’s pretty steep.

Luckily, with any platform and for no money at all you can have access to the extremely powerful mesh-repair services at MakePrintable. MakePrintable’s free cloud-based repair service lets you upload models to repair on their servers, and then download up to three repaired models per month. If you need more repairs than that, then for just $10 per month you can upgrade to their Pro service to get access to more features and unlimited downloads. Since Meshmixer and MeshLab can handle lots of simple mesh problems, the three-a-month restriction is not so bad. But does it work? The answer is YES, and in fact in my experience I have NEVER had a model that MakePrintable couldn’t repair. That includes successfully repairing my Tentacle Bowl, which was made from thousands of recursively-generated overlapping spheres that resulted in very broken internal geometry.

Let’s see what MakePrintable can do with our model. MakePrintable is a cloud-based service that works entirely in your browser, so to get started you just go to makeprintable.com:

Opening and repairing models is free in MakePrintable; it’s only the final download that counts against your monthly total. This means that we can upload our file and see if MakePrintable will fix our file without risking anything. When we upload our model, MakePrintable immediately recognizes its 20 non-manifold edges. Along the right sidebar are a number of fancy options for the Pro/Paid version, but for our purposes we can just use the default free settings.

So, can MakePrintable fix this bad geometry? Yes! Note in the image below that the right-hand model has no non-manifold edges anymore, so we should be in the clear. To download the repaired mesh, choose Save/Export, then 3D Model, then your filetype, then save the file to your computer. This action will reduce your three-a-month download count, so be sure you are happy with the repair before downloading.

In this case our initial broken mesh was very simple, and MakePrintable’s repaired mesh was much finer, with many more triangles. We could have controlled that if we were using the Pro/Paid version, but in this case we can reduce the mesh in Meshmixer and then run through mesh styling TopMod to get exactly the blocky-smooth style we want, which looks like this:

Fixed and ready for Shapeways

Our repaired and remeshed model now uploads to Shapeways, and we can order 3D prints of fancy Deltoidal Hexecontahedron Tealight Rings. Here’s what they look like after printing and photographing for our geekhaus store:

This was just a simple example with a handful of faces and edges causing bad geometry; it can of course get much, much worse. Do you have a broken model? Give these tools a try then upload your model again. Let us know how it goes!

 

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Creating Celtic Knots with Fusion 360

Also published at Shapeways Magazine
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Saint Patrick’s Day is almost here, and to celebrate we’ll do a step-by-step walkthrough tutorial on designing 3D Celtic knots from scratch with Fusion 360. Celtic knots make great pendants and earrings, and it’s easy to put your own style and spin on the knots that you create.

Drawing Celtic Knots from a Grid

There are lots of good tutorials online for drawing two-dimensional pictures of Celtic knots, for example this tutorial from Circle Line Art School:

Celtic knot drawing methods like the one in the video above usually involve drawing a grid of dots and then drawing woven ribbons through the spaces between those dots. For constructing a 3D Celtic knot, it is easier to start with a grid of dots and then connect those dots with splines that you can later thicken into woven pipes. This is actually more similar to how mathematicians think about Celtic knots; for example, the image below is from the paper A Celtic Framework for Knots and Links by computer scientist Jonathan Gross and mathematician Thomas Tucker. Notice that the path of the knot goes through crossing points on the grid, and then we are to imagine that the paths are lifted up or down out of the paper to construct each crossing of the knot.

Tracing Knots with Splines

The quick overview of our technique is that we are going to make a grid of dots in a Fusion 360 sketch, then connect the dots with splines, then shift those splines up or down at the crossing points. This gives us a thin curve that traces out the desired knot, and we’ll be able to sweep a circle around that curve to make a round 3D tube that traces out the knot. Before we get into the details, let’s look at two examples. In general, you want to have as few points as possible long your spline curves; Fusion 360 will be better at drawing a smooth curve between two far-apart dots than at connecting a bunch of close-together dots. On the other hand, you can use extra spline dots to stretch out the path of the spline, and/or change its curvature. Here are two spline paths that define exactly the same Celtic knot, but one has fewer connection points than the other:

The image below shows what these two spline curves look like after sweeping circles around them to make into 3D knots. The very different look and style of these two knots — and even how thick we were able to make them — were determined entirely by how we chose to draw our splines.  You’ll have to experiment with different spline curves to get the look you want.

Step-by-Step Celtic Knot Construction with Fusion 360

Okay, let’s get down to business. We’ll assume that you are a beginner at Fusion 360, and walk through each of the knot-constructing steps carefully. We will trace out curves to make this three-component Celtic knot:

Step 1: Get the software

Download Fusion 360 and sign up for an Autodesk account so you can use it. Fusion 360 is free to students, educators, and hobbyists. For tips on getting started, check out our earlier article Tutorial Tuesday 15: First Steps with 3D Design Software Fusion 360.

Step 2: Create a sketch and make a grid of points

Create a Sketch and then choose Point from the Sketch menu and place points at the locations of the knot crossings and corners. Compare the dots in the screenshot below with the crossings and corners of the three-component Celtic knot shown in the image above. These points will help you keep track of the knot as you make it.

Step 3: Create a spline for each component of the knot

From the Fusion 360 Sketch menu, select the Spline tool. Click dots in order to trace out the path of the knot. Sometimes this will be the entire knot, and the spline will cross itself; this is okay. If your knot has more than one curve in it, then your first spline will only be part of the knot, which is also okay. End your spline at the first dot you chose and then hit Escape to exit the Spline tool.

Step 4: Move the spline up or down at each crossing point

Each point that forms a crossing needs to shift up or down so that the curve of the knot will weave over and under. Right-click on a crossing point and select “move”, then use the vertical arrow to shift that point up or down a fixed amount. You can use Shift-middle-mouse-click-and-drag to rotate your view, and middle-mouse-click-and-drag to pan side to side. Celtic knots always have an “over-under-over-under” alternating pattern at the crossings. (Make sure not to shift the exterior non-crossing points!)

If your Celtic knot pattern has more than one component, then rotate your view back to be directly from the Top and make Splines for each of the remaining components. When you’re done you should have something like this:

When you’re done with the Spline curves, press the Stop Sketch button and move on to the next step.

Step 5: Create perpendicular circles on each component path

Now from the Construct menu, choose the Plane Along Path tool, and construct a Plane on each of the knot components. These planes will be used to construct Circles that we can Sweep along the component paths.

Start a new Sketch and choose one of the new Planes as the base for the Sketch. Then construct a Center-Diameter Circle from the Sketch menu, right at the center of that plane. Press Stop Sketch and repeat for any remaining Planes.

Step 6: Sweep the circles along the spline paths

Finally, from the Create menu, select the Sweep tool. Set one of the Circles as the Profile, then set the corresponding Spline as the Path, and click “OK”. If you get an error then you may have to go back to the previous step and reduce the diameter of the Circle.

Repeat this step for any remaining components of the knot. Pro tip: Sometimes the Sketches will vanish after you create the first Sweep; if this happens then open up the “Sketches” arrow on the Browser list on the left of the screen, and turn the little lightbulbs back on!

You can adjust the Circle diameters as necessary to get the look that you want. To do this, right-click on the corresponding “Sketch” icon in the Timeline bar at the bottom left of the Fusion 360 window, and choose “Edit Sketch”; resize the circle and close the Sketch, and Fusion 360 will re-Sweep the curve with the new circle.

Renders and Prints

Here’s how our Celtic knot looked at the end of this process (and adding some new Materials for style):

To export the knot for printing, open up the Bodies menu in the Brower list on the left of the window, and then right-click on each Body (one for each component) and select Save as STL. We did a scaled-down prototype test print on our XYZ Da Vinci Color printer in black and white:

And here it is uploaded to the Shapeways site. We’ve ordered prints in Full Color Sandstone, Stainless Steel, and Strong & Flexible, and will post photos on our Shapeways geekhaus shop when we get them back!

 

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Targeted Thickening with Meshmixer

Also published at Shapeways Magazine
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When you’re designing for 3D printing, one challenge a lot of designers face is that 3D models often have thinner walls than can be supported by 3D printing materials. Fortunately, it’s a challenge that’s easy to tackle. In this Tutorial Tuesday, we’ll walk you through one way to thicken targeted areas of a 3D model using Meshmixer.

Weak Geometry

Why would you want to thicken just part of a model? One reason is that sometimes a 3D model might get rejected from Shapeways during the pre-production process due to weak geometry or thin connections. This happened to us recently with a Snub Cube model; here’s the picture that was sent to us by the Shapeways team, where the weak/thin connection areas are shown in red:

Although this model printed fine in Strong & Flexible Nylon, the connections between faces were too small to be produced successfully in Stainless Steel. With Stainless Steel, the produce is printed and then infused with bronze; before this infusion, the model is in a fragile “green state.” Or, as the Shapeways team put it when they rejected our Snub Cube: “The model has poor connections that require better support. It may be printable if more connection points are added, or made thicker. Overhanging or cantilevered features will collapse in green state.”

How can we thicken just those connections, without redoing our model from scratch, and without “poofing-out” the entire model and losing the sharpness of our overall geometry? Let’s find out!

Targeted Thickening

We’ll be following a “select, extrude, smooth” strategy in Meshmixer. We will include a lot of screenshots that show our tool settings, because sometimes tiny differences in those settings can make the software act very differently. If your Meshmixer menus don’t look like ours, then try updating to the latest version of Meshmixer.

Step 1: Select

Import your model into Meshmixer. If you don’t see the triangles in your model’s mesh, press the “W” key to toggle their visibility. Then click on the Select tool, set to Brush mode, and make sure that Expand Mode is set to “Crease Angle,” with the Crease Angle Threshold set fairly high on the scale. This threshold controls which neighboring triangles are selected when you use the Brush tool to select a region of the mesh. Specifically, the threshold controls the angle between triangles that the selection tool is willing to select across. A higher threshold will make a tighter selection that won’t select nearby triangles if those triangles have even a slight angle different from the actively selected triangles. The right threshold really depends on the model you are working with, so experiment with this slider accordingly.

Select the region of your model that you would like to thicken. In our case we want to select the inside edges of all the holes and expand them inward, without changing the faces or overall thickness of the Snub Cube.

Step 2: Extrude

While your selection is still highlighted in orange, open the Edit menu in the Select popup window (shown in the upper left in the screenshot above), and select the Extrude option. Make sure that Direction is set to “Normal” so that the extrusion’s direction moves outward from the plane of your mesh selection. Set the offset thickness you need for your model and click “Accept” when ready. Sometimes the menus are a little finicky here, and you may have to reset some options or click away from a text box to get the model to update with changed settings.

Fun math fact: This word “Normal” doesn’t mean regular/vanilla here, it means mathematically geometrically normal, or perpendicular, to the tangent space of the mesh.

Step 3: Smooth

In our example, the resulting extrusion looked a little weird, especially at the hard-edge transitions between the extrusion selection and the rest of the model. Although we like the sharp geometry of our original model, in this case we are printing something that is very small, less than 18mm across. The sharp geometry of our model isn’t really visible at that size, but we worried that the hard transitions from our extrusion might cause the model to fail Shapeways’ automatic or manual checks again. So, we decided to smooth the entire model. The image below shows the result of smoothing after extrude-thickening just one of the holes, so you can see that the connections around the hole we thickened are much more robust than the other connections, say at the back side of the model.

To smooth the model, use Command-A to select the entire mesh, then from the Deform menu in the popup window select “Smooth.” We pushed the Smoothing slider all the way up to 1 so that the smoothing would flow nicely over our extrusion transitions. Experiment with whatever settings work best for smoothing your own model.

Here’s a screenshot comparing our original model with the one-hole-thickened model. Notice that the connections around the thickened hole are much wider, and should be able to support the “green state” stage when printing in Stainless Steel.

Do you have technical suggestions for repairing or resubmitting fragile models to Shapeways? Let us know so we can share your work in future Tutorial Tuesday columns!

 

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As an Amazon Associate we earn from qualifying purchases, so if you’ve got something you need to pick up anyway, going to Amazon through this link will help us keep Hacktastic running. Thanks! :)


Making Meaning

See the original post at Shapeways Magazine
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Okay, it’s 2018 and time to start all over again. But sometimes the process of getting started is… hard to get started. How do you even start planning out a project? Today on Tutorial Tuesday we’ll talk about new beginnings and some projects we’re starting this year, including the sometimes messy process of even figuring out what to make.

Ideas

When you start out with an idea, how do you know what to make? How does it become meaningful? It’s easy to design and print things (here are lots of tutorials), but it can be hard to design that thing that is just right,somehow. The elegant thing; the beautiful thing; the thing that means something. The right thing that somehow is the answer to the question you didn’t even know how to ask.

For me, it usually happens by accident; basically I flail around in the dark for a long time until something just seems right. For example, my partner and I have our 20th wedding anniverary this year, so for some time I’ve been thinking about redesigning our wedding rings. One idea that I really liked was a riff on Courtney, etc.’s elegant Arrow Ring, which you may have seen a million times headlining the Platinum materials page on Shapeways:

arrow 3d printed ring hipster minimalist jewelry

In particular, I was interested in how the two bands float apart from each other. My idea was to turn this ring around so that it was a floating pair of rings in the front, but connected in the back. After twenty years as a couple, it seemed to me that we had learned how to to be our own people while still always having that solid connection behind everything. We talked it over and he agreed it sounded cool and that I should try some prototypes to see how the idea looked in real life.

Prototypes

Late in 2017 I designed some prototypes in Fusion 360 and sent them out to see what looked good, finally settling on a design that looks a lot like two copies of our current wedding rings, with a secret connection in the back. I’ve been wearing around an HP nylon prototype of the ring for a few weeks and I really love it. Here’s what the prototypes look like, and most recent design in silver.

There’s still some work to do; in particular the ring is a little soft in silver and the two bands can bend towards each other if pushed. I might make the connection thicker so the ring will be stronger, or maybe try a harder material. But, I’m not sure anymore that it’s the best wedding ring. Especially because this idea collided pretty awkwardly with another project I’m working on for Valentine’s Day…

Naming and meaning

Specifically, I’ve been working on some jewelry for the sadness of Valentine’s Day. I mean, yeah, Valentine’s Day is great and everything, with all the hearts and candy and Twitter/Instagram photos of how everyone is in love and doing Really Great All The Time. But we aren’t all doing really great all the time. Especially on Valentine’s Day, those who are fighting just to keep it together can feel invisible. I really liked the idea of having some pendants for the hard times. Pendants that make you feel stronger and give you something to hold on to when you’re facing big challenges.

But meaning is what you make it, and also to a large extent what you name it; my goal was to create simple, strong pieces that evoked difficult feelings, and give them evocative names to help reinforce that meaning. Here’s the one I like best so far; it’s called LOSS, and it represents what happens when things break and the center falls out. It’s nice to hold on to and feel the gap, maybe try to close it up with your finger, or put your finger through the arc:

Rediscovery and redesign…

So here’s the awkward part: While thinking about other designs for the Valentine’s Day series I realized that I was already sitting on a perfect design. A ring that looks like a wedding ring, but broken in two pieces — and, even worse, with a perfect name: SEPARATED. So yeah, our new wedding ring is now part of my bleak Valentine’s Day series. Ouch! Thanks, design process! My loving husband very sensibly has already told me that we should to find another design for our 20th wedding anniversary, and yes, ok, he is right. Back to the drawing board!

Happy New Year everyone, and have fun finding your new projects for the year.  :)

 

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Family Design Roundup

Also published at Shapeways Magazine
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Is the family home for the holidays but you’re not sure what to do with them? Are the kids home for break and already complaining about how bored they are? Time to get creative and MAKE something!

This Tutorial Tuesday we’ll highlight some of this year’s 3D design tutorials that even the youngest (or oldest!) of your loved ones can use to make custom and personalized 3D prints in just a few minutes. Choose one of the tutorial introductions below and get started creating in no time!

Getting Started Quickly

Whatever your age or experience, you can jump right in with Tinkercad, a free in-browser design program that’s as easy to use as dragging and dropping shapes onto a workspace. If you want a 3D sandbox to play in, check out how to get started in Tutorial Tuesday 3: Beginner 3D Design With Tinkercad.

Quick Personalized Models

Ready for family D&D night? Create your own custom tabletop character pieces with Hero Forge. It’s easy to mix and match outfits, physical characteristics, and poses with Hero Forge’s intuitive interface. Learn how to get started quickly with Tutorial Tuesday 36: Quick Custom D&D Characters With Hero Forge.

Or, make a family portrait lithophane for your window using Cura. Cura is a “slicer” program for sending 3D models to a printer, but you can also use it to quickly turn photographs into translucent, light-up artwork, following the instructions in Tutorial Tuesday 38: Lightning-Fast Lithophanes With Cura.

If you were dreaming of a white Christmas but didn’t get any snow, make your own unique flakes with the Snowflake Machine. Designing your own custom snowflake is as easy as choosing a random seed and then modifying style parameters with sliders. To get started right away, check out Tutorial Tuesday 45: Make One Billion Snowflakes With the Snowflake Machine.

For the Kids

If the kids are tearing up the house and need something to do, let them have some screen time that actually teaches them something. Here are three design programs guaranteed to keep your kids busy and introduce them to the basics of 3D design. First, the Morphi app for iPad (or desktop version) is really fun to use and intuitive for kids to learn. Find out how to get set up with Morphi in our article Tutorial Tuesday 21: 3D Design Made Simple With Morphi and an iPad.

Second, BlocksCAD lets your kids use code to design simple models, much like the popular drag-and-drop visual coding language Scratch. If they’re learning Scratch at school then BlocksCAD will be second nature to them already. Get started with Tutorial Tuesday 24: Learn to Code in 3D With BlocksCAD.

Finally, let the kids smash things up with the fun design program 3D Slash, where you design by smashing and exploding blocks — with sound effects — to construct 3D objects. Get started in just a few minutes with Tutorial Tuesday 37: Quick 3D Design With 3D Slash.

Happy Holidays everyone, and Merry New Year!!

 

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Design Exploration with Vectary

Also published at Shapeways Magazine
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Today’s 3D printing advice: Figure out what your design software is good at doing and THEN design something, not the other way around.

If you start the design process with a rigid idea of what you want to make, then you’ll have to bang your head against the wall to try to get your software to do what you need it to.  But if you have the luxury of being flexible about what you’re designing, then you can start by sitting down and making friends with some design software, and figuring out what it wants to make. Learn how to drive it, what it’s good at, what it can do that your other software programs can’t, and then see how you can push it to its limits. If you can be open about what you’re going to design, then you have the freedom to let your available modeling software guide the design process.

In a way it’s like making dinner; if you choose a specific thing to make then you’ll have a lot of work to do choosing a recipe, going shopping, maybe even finding specific cookware or learning new techniques, etc. But if you can be flexible then all you have to do is open your fridge and start thinking about what you can put together from the ingredients you already have.

Vectary is perfect for this process: It’s flexible, it can do things you might not expect, and it’s easy to experiment with. We just have to figure out what things Vectary likes to do. Let’s explore…

Getting Started with Vectary

So what kinds of things can you make with Vectary? Here’s a very introductory video showing some simple designs:

From this short video we can already see that Vectary has tools for:

  • Creating low-poly models;
  • Polyhedral designs and patterns;
  • Taking the wireframe of a model; and
  • Remeshing surfaces to make them smooth and organic-looking.

 

We don’t know how to do those things from watching this video, but now we have an idea of some possibilities.

To get started, go to the Vectary site and sign up for an account. Vectary runs entirely in your browser, so there’s nothing to download to your computer. Once you’ve signed in, navigate to your Dashboard and click the “Start Creating” button on a new project. Experiment with the different design tools and see what you can do, then check out the videos and articles below for more guidance and ideas.

Printing from Vectary

One particularly cool feature of Vectary is that it has a Shapeways plugin that allows you to check printability and cost in any Shapeways material, right from the design interface. This cuts down design time significantly, cutting out the steps of repeated exporting, uploading, and testing final revisions of your model. This quick Vectary video Create a 3D printed necklace pendant with Shapeways plugin shows how the process works:

For a more detailed walkthrough of the design process shown in the video, see B. Davids’ Shapeways article VECTARY Tutorial 1: How to Make a Necklace Pendant.

Notice that the video above gives us some additional insight into what design techniques Vectary handles particularly well; in the case of this model those techniques include:

  • Rotating a shape around an axis;
  • Pushing/pulling faces of a low-poly design; and
  • Randomizing patterned features.

 

To activate the Shapeways plugin shown in the video, you have to add it to your Vectary account. Check out the blog post Creating real objects just got easier: VECTARY integrated Shapeways for more information on how to do that.

There’s a catch, but it’s not too bad: To get commercial rights to the models you create in Vectary, you need to “pay with a share,” that is, you need to share your Vectary design on social media. Once you’ve done that, you can sell your Vectary designs as prints or on a service like Shapeways. This is an interesting balance between free and paid software; but for now at least it is nice to have a free way to use such powerful and interesting design software.

Teach Yourself Vectary with Tutorial Videos

To dive deeper into what Vectary can do, take yourself to school by continuing through B. Davids’ very well-done series of articles and videos on Shapeways Magazine. For example, check out the design walkthrough VECTARY Tutorial 2: Make a New Body for an RC Car, and the accompanying VECTARY video Redesign a toy car with Shapeways plugin:

The fun project outlined in the video makes a new chassis for an existing toy car. And, we get some more clues about the long list of design techniques that   knows how to do, including:

  • Sketching and extruding 2D designs from measurements;
  • Selecting, transforming, and moving points, lines, and faces of your design;
  • Joining nearby points to create a closed mesh;
  • Mirroring part of an object for symmetry;
  • Beveling faces and creating holes in a surface; and
  • Adding thickness or offset to your design for stability.

 

You may or may not not want to make a toy car chassis, but these techniques can be applied to many other types of projects.

Next up is the design walkthrough VECTARY Tutorial 3: Create a Minimalist 3D Printed Cactus, with accompanying video Create a twirly cactus with VECTARY:

This video will give you more practice with low-poly modeling and rotational patterns. In addition, we can add these techniques to our growing list of “what’s in Vectary’s fridge”:

  • Rotating groups of selected faces;
  • Loop-selecting edges for beveling, offsetting, and smoothing; and
  • Modifying a template to create variations of a design.

 

Finally, try experimenting while reading the walkthrough Vectary Tutorial 4: Create a Halloween Unicorn Maskand watching the accompanying video Create a Halloween Unicorn Mask with Vectary:

This final B. Davids tutorial video added a couple more items to our what-Vectary-likes-to-do list:

  • Scaling portions of a design with certain symmetries;
  • Creating patterns of new faces to create finer features; and
  • Using Boolean operations like “subtract” with the help of a plugin.

Going Further

From these videos we’re starting to get a good idea of the kind of modeling that Vectary is best at: low-poly modeling followed by smoothing in the final stages. The Vectary design process involves sketching, transforming, and moving faces, edges, and vertices; then pushing, pulling, patterning, and beveling to sculpt a rough object; then “baking” into a smoothed object for a final, more organic-looking design.

If you’re not ready to come back from Vectary school yet, check out the Vectary YouTube channel for tons of design videos. Two of my favorites are the polyhedron-flavored How to create a cubic ring with Vectary

…and the polygon-flavored How to create a geometry bracelet with Vectary:

I’ve played around with a lot of design software, and Vectary is one of the most interesting and promising ones I’ve seen in a while. It’s simple and intuitive, but gives you access to powerful low-poly modeling tools that are usually only found in more complicated or expensive software packages. If you create something with Vectary, let us know so we can feature it in a future post!

 

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Vases in Fusion 360 Two Ways: Lofting and Sculpting

Also published at Shapeways Magazine
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If you’re looking for a unique personalized gift for someone, you still have time to design a custom 3D printed vase and have it printed and shipped before the holidays! According to the Shapeways schedule, you have until December 14 to order models printed in Strong & Flexible plastic. To help you get something designed quickly, in this Tutorial Tuesday we’ll show you two simple but powerful ways to make a custom vase in Fusion 360, and also give you some tips on how to keep your printing costs down.

Make a Lofted Vase

It’s easier than you might think to make a unique custom vase design, even if you’re new to 3D modeling. One good place to start is by following along with the excellent video walkthrough Crazy Vases using the Loft Feature in Fusion 360! CAD For Newbies Tutorial by Maker’s Muse. This video walks you through the process of lofting between different shapes to make cool geometric vase forms:

Or… Make a Sculpted Vase!

Alternately, you could use the video tutorial Fusion 360 – How to Design and Print Your Own Vases by Casual Collisions. This tutorial also uses Fusion 360, but the design path is completely different. Instead of lofting a collection of circles, you’ll work within the powerful Sculpt environment to extrude a circle into a segmented cylindrical mesh, then push and pull the circular segments to form the curves of the vase.

Redesigning for Cost

Of course, larger vases will in general cost more to print than smaller vases, but there are other design considerations that can affect overall printing cost. In particular, if you’re printing with Strong & Flexible Plasticthen the cost of your model will be a combination of Volume (how much material is used in the print) and Machine Space (how much effective space the model takes up in the printer). Remember that Shapeways prints many, many objects in one large print run, with all of the objects packed together as closely as possible. Here’s a video where you can see how that works in practice:

So what does this have to do with vase designs? Well, first of all, if your vase has too small of a neck then Shapeways will be unable to print other objects inside your vase. If your uploaded vase seems unreasonably expensive, check that its neck isn’t too narrow.

Another design factor that might cause your model to take up more Machine Space than you’d expect is tight curves.  For example, here’s a simple vase that we made following the Maker’s Muse tutorial. Notice that the top has some fairly strong curves.

After uploading to Shapeways and clicking on “View Tools” for one of the Strong & Flexible materials, we can see a visual representation of the Machine Space our vase will use. The part shown in blue is the effective space in the machine that our object will use. It’s a buffer of 1mm around the model, plus filled-in areas for anywhere that seems too small or tight to pack other objects into. Notice that the area inside the tight curves is filled in; that’s extra Machine Space that our model is taking up.

You can make a fairly small redesign to bring down the cost of printing your vase. Back in Fusion 360, we selected the top curve and pushed around the spline points to open up the curve a bit. Here’s our original design with the spline points highlighted:

And here’s what it looks like after pushing the splines around:

Updating our model on Shapeways to this new design and looking at the 3D Tools option again, we can see that we’ve reduced the Machine Space considerably. Our small changes dropped the price of our vase by more than $6.50!

Happy vase-making and gift-giving! If you’d like some more background on getting started with Fusion 360, check out Tutorial Tuesday 15: First Steps with 3D Design Software Fusion 360. If you have other favorite ways to make quick vases — in Fusion 360 or in any other program — let us know and we might feature them in a future Tutorial Tuesday.

 

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Make One Billion Snowflakes With the Snowflake Machine

Also published at Shapeways Magazine
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Looking for a fast way to design a 3D printed gift for the holidays? In this Tutorial Tuesday we’ll walk through an easy way to make personalized 3D printed snowflakes for ornaments or jewelry, using the Thingiverse Customizeras a design tool. Specifically, we’ll use a customizable design called The Snowflake Machine that can procedurally generate over one billion unique snowflakes based on random seeds and user-set design parameters. Don’t worry, it’s easier than that just sounded! Here’s a step-by-step how-to guide so you can get your holiday snowflake shopping out of the way. (Or order some pre-made Snowflake Machine ornaments and earrings at the geekhaus shop, if you’re really in a rush…)

Step 1:  Fire up the Snowflake Machine

From your web browser, go to the link for The Snowflake Machine:

From there, click on the button that says “Open in Customizer” (at this point you’ll have to sign up for a free Thingiverse account, if you haven’t done this already). This will open a new page that has controls on the left and an output view on the right. By setting the controls on the left you can control the 3D design shown on the right.

Step 2:  Seed and Style your Flake

The Snowflake Machine customizer uses a random number “seed” to decide where to place branches and plates of the snowflake design. All good children of the 80’s will of course start with the seed 8675309. We’re going to make a hanging ornament, so we set Loop to “Yes.” Under the “set-snowflake-style” menu are a lot of sliders. By pushing the sliders around you can control style parameters such as the lengths of the branches, the fuzziness of your flake, and so on. Here’s our stylized flake:

That’s it for the design phase! For more information on how the Snowflake Machine uses OpenSCAD code to generate snowflakes, and tips on printing snowflake designs in a variety of materials, check out our recent article Trim Your Tree With Mathemagical Snowflake Ornaments.

Step 3:  Download an STL of your snowflake from Thingiverse

To download the snowflake, click on the “Create Thing” button, and give your snowflake a name. After a couple of minutes click on your avatar icon in the top right of the screen, and from the dropdown menu choose “My Things”. From here you’ll be able to click on your completed design and download an STL file for printing.

Step 4:  Upload your snowflake STL to Shapeways

If you’ve got your own 3D printer, you can start printing your snowflake right now. If you want to make a fancy ornament on one of Shapeways’ SLS printers, then go to Shapeways and click “Upload”, then upload your STL file. After a minute or so you’ll see something like this:

There are a few things to notice here. First, the snowflake is pretty big: about 11 centimeters across! If you’d like it to be a different size then you can use the “Resize” button to scale your flake, or you can go back to the design phase and change your target size in the Snowflake Machine customizer. The second thing to notice is that, especially for such a large snowflake, this model is pretty cheap: only about $6 in White or White Polished Strong & Flexible plastic.

Step 5:  Fix any printability issues

The third thing to notice about our Shapeways snowflake model page is that there are some scary yellow caution icons saying telling us that there are issues with the model. If this happens to you, click on the “View Issues” button for the material you are most interested in. The issue is most likely “Wall Thickness”; if so, then click on that item in the left column menu. In the middle of the screen is a description of the thickness required for your chosen material. On the right you’ll see an image of your snowflake with yellow coloring the “Suspect” areas that are too thin. Note that in our model that’s the middle of the snowflake and some of the very tips of the branches:

Luckily, there’s an easy fix: Just press the “Fix Thin Walls” button! (If you don’t see that button, then make sure that the “Show Heatmap View” checkbox is un-checked.)  After a few minutes of computational time, your model should be repaired and printable. Its price might change slightly; for example our model somehow got five cents cheaper after the fix.

Step 6:  Print!

Here’s our model, ready to order and print:

Step 7:  Sell your snowflake design (optional)

If you want other people to be able to purchase your snowflake design on Shapeways, click the “Sell This Design button” at the top right of your design’s product page. Fill out a title and description, choose a category, select the materials you want to make available, set prices, and so on.

Don’t forget that the Snowflake Machine is under a Creative Commons Attribution – Non-Commercial – Share-Alike license that requires attribution, so if you do sell your model, you need to mention in your item description that you used the Snowflake Machine to create your design, and link back to the Snowflake Machine page on Thingiverse. We did exactly that in the Product Details section of the screenshot above.

The “Non-Commercial” part of the license means that you can’t use models you create with the Snowflake Machine for commercial purposes unless permission is given. The good news is that the author of this post is the creator of the Snowflake Machine, so she can give you permission right now. Here it is: If you just want to sell a few fun Snowflake-Machine-created snowflake designs on Shapeways then consider this my official permission for you to do that, with proper attribution. If you want to use the Snowflake Machine for more than that, just ask!

Here’s how our snowflake looks on its Shapeways product page. Notice that the Shapeways site has created a nice render image that shows approximately what the design might look like when printed:

Okay, that’s one snowflake made, but there are still over a billion more you could make, so get moving!

 

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