3D printing is all about the details, and that’s especially true when it comes to tolerances. Defined as the acceptable amount of deviation in a 3D printed object’s dimensions, tolerances must be set correctly for success in additive manufacturing. Shapeways design guidelines often refer to this as the accuracy of a material.

Understanding Tolerances and Variations

While designers may upload 3D models with proper dimensions in mind, there are a variety of factors that can affect tolerances, including:

• Accuracy of slicing software
• 3D printer resolution
• 3D printing material properties
• Required post-processing techniques

Most 3D printing technology allows for a dimensional tolerance of at least 0.1 mm. These tolerances allow for more variation than most traditional manufacturing methods, like Injection Molding or CNC Machining. If deviations are too great, however, 3D prints may fail. Typically, Shapeways recommends tolerances between 0.15 mm and 0.3 mm, depending on project requirements and design rules.

The most common type of tolerance is dimensional tolerance, referring to the acceptable variations in 3D printed objects, while geometric tolerance refers to deviations from shape or structure, such as the angle of a corner.

Surface finish tolerances are critical too, in relation to the texture and appearance of the surface of the part. Factors like layer height, 3D printing speed, and support structures can all impact surface finishes; however, for some parts, aesthetics like surface finish may not be important for functional parts that will not be visible—allowing for faster, more cost-effective manufacturing without intricate attention to aesthetics of the part.

Optimizing Tolerance Settings 

The impact of tolerances on 3D printed parts is not to be ignored, as these details significantly affect functionality and performance.

Tolerances that are too tight may not fit together properly or may be difficult to assemble, while tolerances that are too loose may result in unstable or faulty 3D printed prototypes or end-use products. In the face of major deviations, parts may fail completely due to lack of structural integrity or ability to hold up under stress.

The cost of production plays an essential role in most 3D printing projects, and tolerances are directly related. Tighter tolerances require more precise equipment and production, including more time and effort in manufacturing, raising costs. Looser tolerances yield parts that require less time and effort to produce, reducing costs. Still, lower quality and functionality can raise obvious concerns in terms of reliability and longevity of a 3D printed part.

To plan ahead during the design process, designers, engineers, and industrial manufacturers should keep the following suggestions in mind:

• Consult Shapeways design guidelines for specific material and printing technology being used to ensure that 3D models are compatible. 
• Consider the intended use of the part, and whether it requires precise tolerances or attention to surface detail—depending on the application.
• Evaluate assembly requirements, based on size and complexity of the part.
• Include post-processing requirements while planning the design and production process in order to achieve the desired level of finish in the end product.

With these considerations in mind, 3D designers can optimize their designs and models to achieve high-quality, high-performing end products.

The post Mastering 3D Printing Tolerances: Tips and Tricks for Perfect Parts appeared first on Shapeways Blog.

Sound familiar? If you’ve ever had a model rejected by 3D printing engineers because of wall thickness issues, you’re not alone. While this is a very common issue, many 3D modelers may not be aware of how wall thickness is inspected.

Shapeways prints thousands of parts on a daily basis, with a comprehensive system for inspecting wall thickness based on design and materials.

What is wall thickness and why is it so important in 3D printing?

In taking a closer look behind the scenes to understand the calculations, it’s clear that many 3D models look nice on the computer screen but become troublesome during the actual process of 3D printing.

Difficulties arise when models are too thin, and the scenario worsens in the face of less advanced materials and technology. Attempting to 3D print models with thin aspects will likely result in a failed build, along with fragile models breaking in post-processing, in shipping, or in end use.

Although a complete analysis of structural strength would be ideal, that also presents a complex calculational problem, leading 3D printing engineers to employ more simplified empirical measures with wall thickness analysis. If the model has regions which are thinner than some experimental threshold called minimal wall thickness, we assume that the model has high probability to break; therefore, engineers need tools to see where the model is too thin.

Wall thickness visualization in 3D printing requires a straightforward approach

Consider the example of a small vase (shown below as a cross section). The vase has a very small opening, and when we examine it from the outside we have no idea that it has two offending spots with very thin walls.

Theoretically speaking, it is relatively easy to find the model thickness at any particular point, by walking inside the model along the internal normal until we hit the opposite surface and exit the model. The distance between entry and exit points is a good approximation to the thickness of the model at that spot.

Manual examination can be extremely time consuming. If you have unlimited patience and time that strategy could work though. All the points on the exterior surface of the vase in the example would eventually be examined and the thin regions would be found and identified. Or would they?

Such approximation to the objects’ thickness may sometimes fail spectacularly. In the example, the 20mm thickness at the bottom right corner of our vase poses a problem. In that spot the internal normal points in the “wrong” direction. There is a much shorter distance to the exit point shown in the green arrow. It is unclear how to select the right direction from the starting point. It looks like we would need to analyze all directions from the starting point and select the direction with the shortest distance. This would be very time consuming.

Rather than this manual approach, a better solution is needed. We developed an algorithm that gives all the tedious work to the computer and provides users with visualization of the problematic regions.

Defining distance function and skeleton calculation in 3D models

First, the definition of wall thickness needs to be defined at a particular point. We start from the definition of signed distance function of an object. Signed distance function (SDF) value at any point in the space is the distance from that point to the closest point at the surface of the object taken with negative sign inside of the object and with positive sign outside of the object. One of the advantages of working with signed distance is the ability to work with both—interior and exterior regions of the object. The SDF value on the surface of the object is zero, and it is approximately linear near the surface.

Let’s look at SDF near a region with a thin wall. The SDF is a function of three spatial variables (x,y,z coordinates of a point) and one needs four dimensions to display such a plot. It is simpler and more instructive to look at a plot of SDF along a one-dimensional line (a segment). Only two dimensions are needed to display such a plot, as shown below.

     The behavior of SDF along the segment AB is simple to describe. For points inside of the interval AS the closest point on the surface of the object is point A’ and the plot is a simple linear function – the distance to the point A’ with corresponding sign. For points inside of the interval SB the closest point on the object surface is B’ and the plot is another linear function. The special point S is the point in the interior of the object which has equal distances to opposite surfaces of the object (points A’ and B’). The set of such interior points which have equal distance to more than one point on the object surface is called objects’ skeleton. The plot of SDF near skeleton points has a sharp minimum and switches from one linear branch to another linear branch. It is clear that SDF(S) – the value of signed distance function at the skeleton point S is half of the distance between A’ and B’ which is the natural definition of thickness of the objects at that spot. So, we can define the thickness of object as twice of the absolute value of object’s signed distance function at the object skeleton: Thickness = 2|SDF(S)|.[3] 

Below is a drawing of the skeleton points in color.

Surprisingly, this skeleton has a lot of unexpected small branches (shown in magenta). Those are the points near the object’s edges. They all satisfy the definition of skeleton (with more than one nearest point on the surface of the object), but they are obviously irrelevant to the object’s thickness. If the initial skeleton were followed, the conclusion would be that all the regions along sharp edges have very small (zero) thickness. This conclusion is clearly unsatisfactory and therefore the skeleton is termed a “dirty” skeleton.

Below are details of the dirty skeleton near the edges.

Few skeleton points are marked together with corresponding (closest to them) points on the object’s surface. Points U and V are intuitively good points and are in the middle of the object’s wall. Points E and D are intuitively “bad” points. They correspond to edges and they have to be ignored. The quantitative difference between edge (E and D) and wall (U and V) cases is that those directions to the nearest points are almost opposite in the case of walls, and form an angle close to 90 degrees in the case of edge. This angle can be used as a threshold criterion to remove the edge’s skeleton points and leave only the “clean” skeleton consisting of points corresponding to the object’s walls.

To evaluate more precisely, a “clean” skeleton is needed. Below is an example of the clean skeleton for our example.

Visualizing the skeleton and wall thickness

With the clean skeleton, the calculations of walls and thickness at every point have been determined according to the 2|SDF(S)| formula; however, the skeleton itself may look rather unattractive, and the relation to the original model may not be obvious to the untrained eye. To make the skeleton data accessible, we need to transfer that information to the surface of the original model. 

One way to do this is to create a “thick” skeleton, visualizing all the regions with wall thickness below given wall thickness W. Build a shell around the clean skeleton with uniform thickness W – the thick skeleton, knowing that the thickness of the shell is minimal thickness W—everywhere the shell is thicker than the model we can easily see a printability problem. Below any wall thickness thinner than W poses a problem which we highlighted by painting the surface of those spots in red. 

The skeleton can be used in an even more powerful way, employing the distance function to skeleton, mapping distance to skeleton value to color range—using red as an example for distances below minimal thickness, orange for distances slightly larger (say 1.2x minimal wall thickness), and green for everything above 1.5x minimal wall thickness. We can paint the surface of the original model with values of skeleton distance in those colors.

The visualization of thickness of the original model is complete, but simultaneously exact value of model thickness at a specific spot arises from this simple formula: Thickness = 2*DistanceToSkeleton. 

That complete procedure is used to create the visualization of the model wall thickness in 3D Tools. It is available only if the algorithm has detected wall thickness problems in your model. 

Visualizing in 3D tools

Above is an example of such visualization of a problematic model. This is a small mechanical part, made of stainless steel. That model printed in that material has to have a minimal wall thickness of at least 1mm, but there are few spots where the thickness is only 0.8mm. Those spots are colored mostly in red with some yellow stripes along the boundaries. Those thin spots are in the load-bearing locations of the part and are most definitely the weak spots of the model, requiring the model modification. There are few other places where the algorithm detected the thin walls and highlighted them as well.

Red spots on these two views above are along the holes going under the surface parallel to the part’s top. Those places are not load-bearing and probably may be ignored, but this decision has yet to be made by a human.

Using what you have learned in this blog, you would probably realize immediately that this model has a printability issue. With the visualization, it is easier to analyze and resolve the wall thickness problem before placing an order. The ultimate goal is success in 3D printing, but if you are still having problems with getting the file to a printable state, 3D printing experts at Shapeways are available to help with questions.

Vladimir Bulatov is a 3D graphics researcher at Shapeways, where he has been focusing on 3D printing algorithms since 2012. Beside computer graphics and 3D modeling, his interests include physics, mathematics, and visual arts. 

The post Visualizing Wall Thickness In A 3D Model appeared first on Shapeways Blog.

Can you explain chromatic wood type?

Chromatic wood type became very rare after the early 20th century; much of it was destroyed. William H Page was the major manufacturer of chromatic wood type — letters relief-printed from multiple blocks that overlap to make additional colors — in the mid to late nineteenth century.

Could you please describe your work with Purgatory Pie Press?

Purgatory Pie Press is one of the longest running artist presses, founded by letterpress printer Dikko Faust. He and artistic director, Esther Smith make limited editions and artists books. Esther designed and produced a reprint of W H Page’s 1874 Specimens of CHROMATIC WOODTYPE with Rizzoli publishers. We decided to collaborate to recreate a W H Page chromatic typeface. Dikko researched Page and found his original drawings of Etruscan. Dikko also found examples of the typeface printed in period British circus posters. There are no examples of original Etruscan type surviving today that we know of.

Why did you decide to use 3D printing and Shapeways?

We wanted to develop a process that was consistent and economical. We were faced with problems that could only be solved by repeated experimentation. We had prototypes made and remade until we had a working piece of type that could be used on a traditional letterpress. You can imagine the excitement of successfully printing the piece for Esther and Dikko’s talk at the Metropolitan Museum in 2018 — a 3D printed piece of type and traditional wood type both designed in the 1870s printed together on a press from the 1940s. Many antique wood type collections are incomplete and unusable. The process we developed can be used to create the missing type with 3D printed blocks in any size needed.

What stages of the process did you use Shapeways for?

We used Shapeways for our early and final stage prototyping. In order for the type to work, it had to integrate seamlessly with the original vintage type.

What challenges did you face in regards to finding the right materials?

We needed to be able to create prototypes in different materials and test them on the press. We needed a material that could reproduce fine detail with a truly smooth surface. The press produces a sizable force on the plastic typeface. In order for the type to work properly, it must be strong and dimensionally stable. The plastic must also be durable to stand up to repeated use.

How did Shapeways help you address these challenges?

Shapeways provided us with the ability to test with diverse materials with rapid turn around so that we could develop a working repeatable process. The ability to test different materials and manufacturing methods in one place in a cost-effective manner was a tremendous benefit. Shapeways gave us access to industrial scale printers in the prototype phase so that we could scale up the process without having to repeat testing. The result was impressive: We printed over 200 BID bookmarks with no noticeable degradation of quality and the block is still usable for future use.

Want to learn how Shapeways can support your business with rapid prototyping and high-quality 3D printing? Partner with Shapeways to elevate your project with on-demand 3D manufacturing.

The post Reviving an Early 20th Century Printmaking Practice With Modern Technology appeared first on Shapeways Blog.

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!

The post Just in Time: Last-Minute Holiday Gifts appeared first on Shapeways Blog.

Black Panther was a huge force at the box office, and many of the unique visuals that came out of the nation of Wakanda are thanks to 3D printing. At Shapeways, we want to make the wonders of 3D printing accessible to all, from hobbyists to dyed-in-the-wool professionals. Today, we’ve found a couple great versions of the helmet of everyone’s favorite Wakandan monarch, T’Challa.

Uncle Jessy and Do3D Make Magic Together

YouTuber and avid 3D printing enthusiast Uncle Jessy has amassed quite a following, with over 68,000 followers, and this video chronicling his printing and painting of Do3D.com’s Black Panther mask has netted over a million views. Jessy used Do3D’s STL file, and then finished the job with his painting skills. We have to say, the finished product looks amazing. Its staggering amount of detail makes it an auto-include in any serious Black Panther cosplay – think of all the time you’ll save not meticulously carving and forming worbla with this! You’ll still need to paint it, of course, but you’ll have plenty of time to practice that while you wait for it to arrive.

Daniel Pecoraro’s Black Panther Mask

“Black Panther” by Daniel Pecoraro (Guidomalan) on Thingiverse

It might not be as detailed as Do3D’s mask, but this mask created by self-described student and engineer Daniel Pecoraro still looks screen-accurate and amazing. And as a wonderful cherry on top, Daniel put his file up on Thingiverse for complimentary download so everyone can enjoy.

We can’t wait to see how you celebrate the release!

The post Create Your Own Black Panther Mask for the Upcoming Premiere appeared first on Shapeways Blog.

How do you capture a texture? As a kid you would grab a crayon and a white sheet of paper to reveal and replicate the surface. Today, you would probably snap a photo and fill your Instagram with the unique surface textures or patterns. But hold up, we live in the future and can create a real-life, wearable design out of those patterns and textures.

With photogrammetry you can scan your favorite item or texture and turn it into a ring. Accurately replicating a surface texture can be difficult to do through traditional 3D sculpting. Using 3D scanning, you can precisely capture the texture with ease.

In this guest tutorial, Bernat Cuni of Cunicode has tested and created a step-by-step instructional on how you can create your own textured ring. Using Autodesk Recap and an iPhone, Cuni was able to replicate the bark from a pine tree in the French Pyrenees.

With new applications, creating objects using photogrammetry has become easy and inexpensive. For those unfamiliar with the term, Photogrammetry is the process of stitching together multiple images from a real-world environment or object to then form a high-quality 3D model, map, measurement, or drawing. In our case, we will be using the technology to create a 3D model.

Before we begin the tutorial, let’s go over what you will need in order to create your textured ring.

1. Digital Camera 
   • You can use your phone, no need to go out and purchase an expensive camera.
2. Photogrammetry software 
   • Free: 3DF Zephir: Windows
   • Paid: Autodesk ReCap Photo: Windows
   • Paid: Agisoft Photoscan: Windows, Mac, Linux
   • RealityCapture: Windows
   • Open Source:Regard 3D: Windows, Mac
3. MeshLab & Meshmixer
   • Open source and free software for processing and editing 3D meshes. Works on Windows and Mac.
4. 3D Modeling Software
   • You can select your favorite modeling software to edit the ring to your specifications.

We’ll show you how to create this ring, which you can then print in any of Shapeways’ metals

Step 1: Select Your Texture or Object

In order to begin, select the object, texture, or pattern you would like replicate and use to create your ring. Bernat has selected a tree within the French Pyrenees.

It is best to avoid shiny or transparent objects as they are difficult to capture.

Step 2: Take Images of Your Texture or Object

To begin you will need a set of photos of the object to process them into a valid 3D model.

Using a digital camera (your phone will work), take images of the object. Make sure to get all angles of the object from the same or close to the same distance. Bernat went around the object 3 times (one at eye-level, one looking up, and one looking down) in order to ensure that every angle was captured. In total, Bernat took 56 photos at 2049 × 1537 pixels. You do not need this exact amount but it is helpful to understand that the more photos you have, the more data you have to work with.

Note: It is important to have consistent lighting conditions while you are shooting your object. If you are outside, it is best to shoot the images on a cloudy day to avoid shadows. If you are inside, bright lighting is necessary to receive the clearest photos with the most data. Do not edit the photos, as they should contain the EXIF data for better processing (lens used, shutter speed, etc).

Step 3: Upload and Process Photos

Upload your photos to the photogrammetry software you selected above. Bernat used Autodesk’s RecapPhoto and processed the 56 tree images he took. For the photogrammetry software you selected, follow its instructions on processing and stitching your photos. This can take anywhere from a few minutes to a few hours depending on the settings and photos you have chosen.

Step 4:  Clean Up & Cut Mesh

The mesh that was then revealed was larger than necessary and contained more data than for the object he was looking to create, including nearby trees and buildings. Bernat went ahead and cleaned the mesh using MeshLab. He selected the bark and tree he wanted to keep for his design and deleted the rest of the scan data.

The bark was now isolated and could be cut and brought to scale. You can then download the file from MeshLab and import the design into MeshMixer. From there use the PlaneCut tool to trim the mesh to the desired thickness. 

Step 5: Create a Mesh Solid

This can be done with another modeling software of your choice. Bernat used Rhino to turn the surface into a solid, using the Mesh command. Once the design has been turned into a solid, you can then edit the design to create a ring. Cut a hole from the center of the solid and fillet the interior edges.

Step 9: Upload to Shapeways

Once you have scaled the design to your appropriate ring size, you can upload directly to Shapeways. You can upload multiple sizes to sell in your shop or print just for yourself.

You’re ready to print!

Watch Bernat’s explanation of the design process through his video below:

For more inspiration from Bernat Cuni, check out his MoonRing. where he created an accurate texture of the moon using scanning data.

Inspired? Print your design

The post Tutorial Tuesday 53: Create a Textured Unisex Ring With a Phone and Photogrammetry appeared first on Shapeways Blog.

Worry beads are the original fidget spinner. Bracelets made from worry beads were invented by the Greeks to help to pass the time and keep nerves at bay. Now, Gordon Lardi, a designer and engineer, has created an all new set of rope-like worry beads using SolidWorks (Note: you can use any parametric modeling program to create this design, for free options try Fusion360 or OnShape) and Strong & Flexible plastic. Using the iterative design process, Gordon discovered that his design had a super-satisfying “fidget bead” quality. Learn how to create your own in Gordon’s simple 5-step tutorial. 

Step-by-Step Interlocking Bracelet Tutorial

By Gordon Lardi 

Step One: Design a single bracelet link. 

Lardi has used a capsule shape for the individual beads in order to give the bracelet some weight and depth. From the first step in the tutorial you will notice the need for parametric modeling software (SolidWorks or Fusion360). These tools allow you to easily go back and edit dimensions where needed without having to redesign the entire bead or bracelet.  

Step 2: Twist single link.

Flex the entire body of the bracelet link to give the bracelet the rope twisting appearance. When twisting the bead in this way, you may reveal sharp edges. At this step you will want to fillet or round off those sharp edges.

Step 3: Create chain of links. 

Now that the bead is complete, create a linear pattern of the links to create a single bracelet. Set the number of links appropriate to your desired bracelet or chain size. 

Step 4: Check how your links fit. 

Inspect the chain by temporarily splitting the design in half. You want to make sure that your links are not touching or are too close to the connecting link. This will ensure that while your chain is printing, the links do not fuse together. Lardi recommends that you at least provide 0.5mm – 1mm of clearance. 

Step 5: Create Fastener

The final step in creating the rope bracelet is designing the hook or fastener. Lardi was looking to create an “uninterrupted rope appearance,” so he developed a final link that would blend in with all of the other links. Lardi designed a snap on hook by trimming the opening slightly larger than the width of the link. This would allow the hook to easily snap on and off. 

Once the initial design was complete, Lardi ordered a prototype of the design in black Strong & Flexible nylon. Using the iterative design process, Lardi ordered the design three times with slight dimensional changes in between to get the design and fit just right.

ready? print your design

With the final product received, Lardi discovered an unintended, fidget-like quality to his design. Each of the links snap into a S like pattern, much like the worry bead. 

The post Tutorial Tuesday 52: Design Your Own Satisfying Fidget Bead Bracelet appeared first on Shapeways Blog.

In this tutorial, you will be introduced to Autodesk’s Fusion360, a very powerful and free cloud based 3D modeling software. Meaning, you can access your work from any computer with a wi-fi connection and the Fusion360 application.

With a few simple steps you can go from a blank canvas to a completed pendant design!

All set? print it now

You can follow along with each step of the tutorial (and get some extra design tips) below:

Step 1. Create the shape of your pendant.

In this example Dee uses the rectangular tool to create a bar pendant. However, you can use the circle tool or line tool to draw any shaped pendant you would like. Select the top plane, then draw your pendant shape. Imagine you are looking at the pendant from an arial view. Next use the measurement tool to select one side/line of your shape. You can then select the measurement to change it to the size you desire.

Step 2. Add the holes for the chain

For this tutorial, you will need to create a holes in your pendant in order to have the design hang from a chain. Using the line tool, you can create guidelines to help make sure your chain holes are centered and evenly spaced. You will then use the circle tool to create the holes for your chain. You will want to make sure that these holes are at least 3mm in diameter so that the chain can easily fit through.

Step 3. Turn your drawing into a 3D Object/Pendant 

Using the extrude tool, you will select the pendant design. As a note, make sure that you do not have the chain holes selected while you are extruding as the chain will need to go through these spaces. Enter the thickness you would like to extrude; this will determine how thick you would like your pendant. In this tutorial we make the pendant 2mm thick.

To give the edges a slight rounding we will want to use the fillet tool. Select the fillet tool, then select all of the edges of your pendant by holding shift and selecting each side. Then you will enter 0.5mm in the radius field and hit enter. This will then give your whole pendant a smooth edge.

Step 4. Engrave your custom message in your pendant

Now that your pendant is created, it is time to add your custom text. Using the text tool select the area on the pendant where you would like the text to start. Type the name or saying in the text field, and it will automatically appear on your design. You can then drag the circle indicator next to your text to rotate the message or move the text’s location on the pendant using the compass. In the height field, enter the size of the text you would like on your pendant.

Now you will need to engrave or extrude the text so that it will be a part of the your 3D object. Select the extrude tool then select the text. You can then select “cut” if you would like the text engraved or keep it on “new body” if you would like raised text. Now enter the height or depth of the text you would like to add. In the height field enter either -1mm if you would like it engraved or 1mm if you would like raised text. Hit enter, and you have created your first pendant 3D model!

Step 5. Download your file and upload directly to Shapeways

Select “save” and give the design a name, then you can add it to the folder you would like. Then select “save as an .STL file” and save to your desktop.

Once you download your completed pendant, you can upload directly to Shapeways. This means it will be ready to be printed in any of our 60+ materials and finishes including gold, brass, bronze, silver, or steel.

Ready to print? Upload here

For more on how to create with Fusion360, you can check Five Petal Studio’s other tutorials or Fusion360’s tutorial hub.

The post Tutorial Tuesday 51: How To Create a Custom Pendant in Five Steps Using Fusion360 appeared first on Shapeways Blog.

Meet Donny!

The process of designing it was really long as I often would model it one way, then realize I wanted (or in most cases, needed) to do it totally differently. In preparation for this project I’d also bought the ZBrush Core x Walcom package, so I upgraded from the free stuff I’d been using up to this point. Big steps! I took the prototyping process really seriously for this project because, without an actual guinea pig to measure and use as a model, I had to get creative.

After saying goodbye to my beloved test model (eggplants eventually have to be thrown out… we learned), I was luckily able to buy a scan of a guinea pig from Hum3D, which I used as the base. I wish I’d taken more screenshots of the design process because this project did not come easily to me, but it turns out I only really took one — which is of the initial shape I’d created in Blender before sculpting it in ZBrush Core.

I found that the hardest part of this project was trying to figure out how the heck to make the two parts I designed interlock. I figured I could sculpt this as one large segment of armor, but if the guinea pig has any desire to wiggle around, it wasn’t going to be comfy.

So after having attempted a looped connection, I decided it would be more effective to meld 3D modeling with some good old-fashioned string. By designing each segment with loops attached to the inner side of the armor, some string could be used to tailor it to the length of the guinea pig while allowing a little wiggle room (literally, in this case).

I sent the first print to the MiniWarGaming team, but it seems that I have some tweaking to do on the design so that the model doesn’t cover Donny’s ears while also fitting his crazy, adorable geometric fur. Josh let me know that this photo is just an example of Abyssinian fur but the email made me laugh. We also chatted about the necessary changes during a Skype call — both helpful steps in the design iteration and feedback process!

In non-guinea-pig news, I had another project opportunity pop up, but I couldn’t figure out an easy way to pull it off. My aunt had asked if I could design a little gnome with her neighbor’s face on it (apparently they try and outdo each other with weird gifts). I’d found this AI-powered tool that turns a selfie into a 3D model but couldn’t figure out how to import the model into Blender or ZBrush Core with the corresponding color mesh. Anyone have any ideas on how I could have pulled that off?

In any case, stay tuned on updates to this saga!

The post Out of Shape 8: Conquering the Guinea Pig Armor appeared first on Shapeways Blog.

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!

The post Tutorial Tuesday 50: Using Meshmixer to Make 3D Models Thick Enough to 3D Print appeared first on Shapeways Blog.