The VOLTA is a compact “20/20” electric bike for inner city use. The bike is light-weight and clean, and offers everything for a practical and cool urban commute. In the design, we have been looking for a clean and readable expression. To achieve this, we have created a visual break-up between the core frame (which also holds the batteries) and the “extremities”: the handlebar/basket unit on the front and the universal accessory holder on the back.

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Seven years ago, during an environmental crisis—the BP oil disaster—and a media blackout, where information about the spill was being tightly controlled, hundreds of people came together to collect their own data. Using just cameras, attached to balloons or kites, the Balloon Mapping Kit was born, and with it, the Public Lab community.

7 years after "grassroots mapping", Public Lab is back with an even more accessible Do-It-Yourself way to take aerial photos: Mini Balloon and Kite Mapping Kits.

At half the cost of the original, these kits are designed for portability and for a new generation of smaller GoPro-like cameras. The new Kite kit makes use of an extremely compact (but octopus-shaped) kite with no spars.

View the full project here

Editors Note: Teshia a contributor to Core77 and Chief of Staff at Berlin-based startup Senic, who are currently building their second product COVI.

When we began building COVI, it was on the heels of of our first product NUIMO. NUIMO is a controller for smart devices like Sonos and Phillips Hue and, like COVI, was funded via Kickstarter. 

Our vision for Senic has always been big—a hope that we can bring technology into the home in such a way that it doesn't distract from fundamental 'human things' like relaxation, relationship building, health and creativity, but actually promotes them. 

COVI came about as a response to the hundreds of speech-enabled gadgets on the market from big and small companies. In designing such an object, we encountered a number of decisions that needed to be made (should it be a Lamp... Speaker... Hub....Mysterious Talking Cylinder). In the end we decided that the object should be the right balance of features—wrapped in an object that we could actually envision owning—a piece that was as much furniture as technology. 

COVI on Kickstarter 

COVI consists of three big things: a lamp, a speech-interface and an open-source smart home hub. No surprise, all of these exist on the market in some form already. 

However, we had yet to see a 'hub' (e.g. a device that can control and connect multiple smart devices and can allow a user to set an automation) that looked like something that could blend into a living room. Likewise, many of the speech interfaces on the market have somewhat mysterious shapes and don't provide utility beyond their speech interface. 

From this idea—that tech could be less like our router we hide on a bookshelf and more like our favorite piece of furniture, COVI was born. Building a smart lamp offers a lot of room to play as a designer, allowing another visual output and affecting one of human's most important psychological and environmental factors—light. 

To produce COVI, we needed to bring together several skill sets including industrial design, software development, psychology, electrical, mechanical, embedded systems and audio engineering. Likewise creating a consumer electronic that relies heavily on glass as COVI does is a unique challenge, since most smart home products use less expensive processes such as injection molding. 

Design of COVI

Searching for the correct form factor for COVI led us to explore ways in which people used light historically. In the south west of Germany, coal miners carried gasoline lamps that they would take underground. Given that some of our team member's families worked in coal mines—this became an important inspiration for COVI. The knob that regulates the amount of gas to the traditional lamp became a dimmer switch inviting the user to touch and interact with COVI.

Like with NUIMO, we did our initial prototyping by hand in our studio using foam and a (precarious) homemade lathe. We made several foam models to try and hone in on the shape of the lamp before translating the models into glass. 

Once the final volume for COVI began to take shape, we started to look for manufacturers that could help us prototype the first COVIs for the Kickstarter campaign. 

Glass Blowing + Metal Lathing 

Glass was the obvious choice for COVI. We needed a material that would diffuse the light and look beautiful in the home. The vast majority of smart home products use injection molded plastic parts that can look cheap—something we wanted to avoid as we blended tech and interior design. 

Together with local craftsman Berlin Glas e.V., we created the first COVI shades. Each of these first COVIs were handblown individually by craftsman in pairs of two. Shaping the outer surface of the shade is done by hand with only a thick stack of wet newspapers to press the outer surface into the final form. 

As glass has a mind of its own, and each handblown shade is slightly different—we then had the challenge of bringing together the aluminum base that houses the electronics, microphones, speakers and LEDs. To create the base, we used the extremely precise process of metal lathing. 

Raw aluminum pipe Sawing the pipe to lengthCOVI bases prepared for lathe 

Each raw aluminum pipe was cut to a specific size that approximated the height of the base. To fine tune the form of the base, a metal lathe was used to shape and thin the walls of the pipe.

Once the base is shaped to the final form, it is taken to be glass-bead blasted to achieve a texture that hides dirt, oil and fingerprints. The last step is for the bases to be anodized to their final color before assembled into COVI. 

For COVI, the mechanical housing and overall form must be in perfect alignment with the electronic components and software to allow such things as speech interface and hub functionality. Often, it can be tempting to think of the housing and visual design of the object last, a "tech first" approach that many larger companies take when designing smart home. 

With COVI, the hope is to challenge the notion of how technology should look and feel—especially in the home. 

COVI is currently crowdfunding on Kickstarter. For more information on the design and manufacturing check out Senic's website.

This meditative build video from John Heisz ends violently, with CMYK in place of blood. It's also a perfect metaphor for why we build low-tech things by hand. Infuriated by his malfunctioning hi-tech printer, Heisz builds an enormous stake maul (think Donkey Kong hammer) in order to send the printer off with a bang:

Tandem Product Design is currently looking for talented mid level industrial Designers with 1-2 years of Industrial Design work experience to join our award-winning design and development studio in Santa Monica, California. Your position involves a broad range of responsibilities including ideation sketching, 3D modeling, rendering, product research, presentation preparation. Your talent will have an positive impact on the final products which will potentially being the leaders in the market.

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More proof that there's always room for design improvements, even in the most established of objects. The humble doorknob hasn't changed much since its invention, with the exception of lever-style knobs that ease operation for those with grip issues. But Brinks Home Security has designed an innovative line of doorknobs that considers how people actually use them, meaning when their hands are already occupied. Check these out:

You can learn more about BHS' Push Pull Rotate line, as it's called, here.

First off, we love that there's a show called "Pingsider" that takes you deep inside the world of ping pong. Secondly, ping pong balls are one of those items that sound deceptively easy to make. But this look inside a factory in China, where table tennis is practically the national sport, shows you just how seriously they take their production:

I think the rigorous testing and inspection procedures, conducted in both hi- and low-tech fashion, were the most surprising. Oh, and how much of a bummer was it that they won't show us the crucial, proprietary step of cleaning up the equator? Do any of you production method gurus know how they trim it up?

Take a moment to imagine what a Nike headquarters in the heart of NYC would look like. Now picture that times 10, and that's what it actually looks like in real life. This week marks the first week Nike employees get to work in their new 147,000 sq ft NYC home. After the tour we took last week, we've been wondering: Is there space for us?

The office is so massive, it's difficult to pick a starting point, so here's an overhead view of the main outdoor terrace. You can casually gaze upon both One World Trade Center and the Empire State Building from this terrace, and you can even see the Nike logo garden from the top of the Empire State Building. Perhaps even Google Earth? To be determined.

Also worth pointing out are the terrace's hardwood floors, which are made of reclaimed cedar from old water towers removed from buildings around the city.

We appreciate that the office hints at classic NYC attractions without being corny. In addition to standing between two of the city's most famous buildings, spaces like the one above are subtle nods to popular NYC locations like the High Line. When sitting on the steps above the staircase, you look out through the glass similar to the iconic lookout point on the path.

There's also a pretty sweet orange VW van, a nod to Nike's original channel of retail (Bill Bowerman and Jeff Johnson would sell Nike shoes at track meets from a similar van). 

The star of the show is this gigantic 4,000 sq ft basketball court on the second floor. Designed as a collaboration between Jordan and Nike, the court features both logos and can host a lot of people.

Other details include these sleek tiles, drawn on-site by NYC artist Micah Belamarich, which represent both Nike and NYC athletic culture. 

These embossed tiles, which abstractly represent basketball.

...And these tiles, which have assembled into a cool Michael Jordan homage.

Not pictured but worth noting are a wall made from Poplar tree bark, intricate ceilings made from recycled textiles designed by Miniwiz, transforming desks in collaboration with Mash Studios, and a large custom food truck featuring artwork by Dark Igloo. 

The main problem Nike will face is figuring out how to get employees to leave every night.

LUNAR cofounders Jeff Smith and Gerard Furbershaw sought to create a sculpturally oriented bench that provided social interaction opportunities for passersby in outdoor public places and museum and gallery exhibition spaces. People have an innate desire to engage, interact and play, yet there are a limited number of public spaces that enable this. Smith and Furbershaw looked to the playground seesaw for inspiration, as most people have experienced this form of interactive play as children. 

They believed that leveraging the seesaw and enhancing it with a sophisticated design would lead to a compelling experience for people visiting outdoor public places and museum and gallery spaces. Although it is possible to engage in solo play, interacting with another person or persons is oftentimes more rewarding. With that in mind, they named the bench 2toTango after the phrase, "it takes two to tango."

Figure 1: 2ToTango in a public square

Smith and Furbershaw sought to create a sense of magic in how 2ToTango functioned, as if it as if it teeter-tottered about its sharp visual fulcrum corners although that motion would actually be driven by an internal mechanism. The requirement was for the bench to remain horizontal when no one sat on it. When a person sat on one side of it, 2ToTango needed to descend slowly towards the floor or ground and stop within two inches of it to prevent the bench's end corners from being damaged and to ensure it didn't pinch people's feet. When that person left the bench, it needed to return slowly to its horizontal position. If one or two or people sat on both sides at the same time, the bench was to teeter-totter in relation to where they sat and where they might move, depending upon whether and how they chose to interact with each other.

Figure 2: 2ToTango tilted to the side the person is sitting on it. Figure 3: 2ToTango in a horizontal state of balance with the lighter person on the left farther away from the fulcrum than the heavier person the right.

LUNAR's Engineering Team was tasked with creating a mechanism that achieved the desired motion. Mechanical engineer Bob Lane developed and refined the final mechanism design. It relies on return springs and pneumatic cylinders. When no one is sitting on 2ToTango, return springs keep the bench in a horizontal position. If a person sits on one side of the bench, that side lowers slowly, dampened by the pneumatic cylinder's inlet flow control valve on that side (see Figure 2). If another person sits on the other side, the bench teeter-totters in relation to where they sit and where they might move, depending upon whether and how they choose to interact with each other (see Figures 3 and 5). If both people leave 2toTango, the return springs bring it back to a horizontal state of balance (see Figure 1).

2toTango is fabricated as an 8 foot long welded and ground aluminum monocoque structural skin. A steel base plate embedded into the floor connects to an internal fame. The frame connects the teeter-totter's pivot, the two internal pneumatic cylinders and the two return springs. The outside ends of the pneumatic cylinders and return springs are affixed to the bench's structural skin via structural ribs. Tubing between the pneumatic cylinders maintains equal pressure between them.

Figure 4: Mechanism layout

This teeter-totter design engenders a number of ways of engaging, from beholding its beauty and not interacting with it physically to just sitting, play, and psychological gamesmanship.

Solo State

2ToTango's internal mechanism keeps it horizontal when not in use. When a person sits on either the left or right side, the bench descends slowly to within two inches of the floor (See Figure 2).

Cooperation State

One or more persons sit on both sides of the bench perpendicular to its axis, peripherally aware of the other(s) and how their positions interact to affect the tilt of the bench. Some or all of the individuals seated on one or both sides either move towards or away from the fulcrum to interactively create an imbalanced tilted or balanced horizontal state (See Figures 3, 5 and 6).

Figure 5: The persons on the left and right cooperate by sitting the appropriate distance from the fulcrum to create a horizontal state of balance.

Domination State

One or more persons sit on one side of the bench and move(s) toward or away from the fulcrum to create an imbalanced tilted state between them and an individual or people seated on the other side (See Figure 6).

Figure 6: The two people on the right tilt the bench and lift up the person on the left.

Engaged Interaction State

One or more seated persons straddle the bench while facing an individual or people on the opposite side. The individual or people on both sides move towards or away from the fulcrum to interactively create an imbalanced tilted or balanced horizontal state.

Disengaged Interaction State

One or more people seated on one side of the bench face away from an individual or people seated on the other side. As those seated on either or both sides move towards or away from the fulcrum, they create imbalanced tilted or balanced horizontal states. Although interactions are taking place, they are coincidental and none of those seated are aware that the interactions are occurring with the individual or people seated on the other side.

2ToTango's triangular cross section twists 180 degrees from the left and right sides, which provide flat top surfaces for seating, to a sharp edge in the bottom center to create a visual fulcrum. The resulting rotated form that transforms from the flat seating surfaces on the ends to the teeter-totter fulcrum in the center clearly reflects its function. The triangular cross section on the left and right sides also helps to minimize 2ToTango's visual mass. The four bottom-facing polished aluminum surfaces reflect the floor or ground material, blending the bench into the surrounding environment. This creates a sense of transparency and makes it appear almost as if people seated on it are floating above the ground.

2ToTango enhances the experience of visiting outdoor public places and exhibition spaces by providing functional seating integrated within a piece of striking kinetic sculpture. It also enables passersby to interact with it in a number of ways ranging from simply beholding its beauty to playing, to partaking in psychological gamesmanship. Although engagement in solo play is always an option, it is worth remembering that for the ultimate experience, "it takes two to tango!"

Using the names of materials as adjectives can be pejorative: "He gave a wooden performance," "These people are so plastic." But when your boss says s/he wants "concrete results," it implies rigor and success.

Concrete can be an unforgiving material that requires careful design, but the reward is an object that will endure. For those of you up to the task, Quikrete is sponsoring a One Bag design competition where they want to see what you can create using just a single bag of their product (of any mix).

First prize is $2,500, with $1,500 and $500 serving as second and third prizes. The deadline is July 9th, so you've got a little under two weeks to get cracking. Er, to get going.

Rules and regulations, as well as photos of last year's winning objects for reference, are here.

NAWA is an ultralight, durable sculpture made up of 35 steel arches, making an open gate through which anyone can walk freely. Its bionic form and polished surface reflecting its surroundings creates the effect of a naturally growing sculpture with a constantly changing look throughout the day.

The sculpture is a part of the European Capital of Culture 2016 celebrations, whose main slogan is “metamorphoses of culture”, i.e. shifts occurring in the domain of culture, communities and the city itself.

View the full project here

It's always fun to watch someone design out loud. Here Izzy Swan creates a folding table that folds into a storage unit, and he builds it primarily out of plywood scraps. This seems like it'd be useful for college kids or the itinerant, as moving a table is typically a pain in the neck—but here the table could actually be used like boxes to carry other stuff.

"I don't think you can design anything just by absorbing information and then hoping to synthesise it into a solution. What you need to know about the problem only becomes apparent as you're trying to solve it." Richard MacCormac. The argument here is a simple one, but one which I believe has been swept under the design practice rug for quite some time.

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I'd be happy not to know what a drum machine is, but I do because I've watched the rooter guy use one to unclog our sewer line. What is a drum machine? It's a large motorized version of the hand snake a homeowner might use to clear the drain from a sink or other small fixture.

Milwaukee Tool recently unveiled its first drum machine—actually, a sectional drum machine because its cable can be lengthened by joining it to another. I wouldn't normally be interested in such a machine but I am because this one is a complete rethinking of a mature product whose deficiencies have been known and accepted for years.

Conventional drum machines are used to clear long runs of 3-inch and larger drain lines. They typically weigh 70-plus pounds and have wheels to make them easier to transport.  But it's difficult to get them up and down stairs and haul them in and out of buildings without creating a mess—dirt tracked in on the wheels and filth that drips from the cable.

This is the machine without the drum in place.

Milwaukee's M18 FUEL Sectional Drum Machine is powered by an 18-volt tool battery and is the first of its kind not to require a cord. It weighs 50 pounds with the heaviest cable and can be split in two for transport.

Built-in straps allow the machine to carried in and out of the building like a backpack while the drum is carried by a handle. 

Straps make it possible to carry the machine like a backpack.The drum has a built-in carry handle and is easily swapped for drums containing different sizes and types of cable. The pulley on back will engage with the drive belt of the machine.

When the drain tech arrives at the work area the drum is rejoined to the machine by dropping it into a sort of cradle and locking it in place with a pair of suitcase style latches. Should a different size or type of cable be required  a drum containing it can be easily swapped in. 

The cable is enclosed so unless someone tips the machine it's unlikely to dribble the dreaded "poo stew" on the floor. After clearing the drain the housing surrounding the drum can be opened, cleaned with a hose, and left to dry.

I won't go into the specs because they won't matter to you unless you're a drain tech or plumber. 

What impresses me most about this product is how different it is from every drain cleaning machine that came before; it's cordless, easy-to-transport, and flexible—because drums containing different types of cable can be swapped in as needed. 

The M18 FUEL Sectional Drum Machine (model 2775) is expected to launch in November 2017. 

The video below was shot by the folks from Coptool at a presentation I attended at a recent Milwaukee media event.

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A team within Adobe is looking for a UX designer who can help us evolve a project supporting, connecting and amplifying a global community of emerging artists who are using creativity as a force for positive impact This is a special role, requiring big-picture thinking. You’ll take a deep look at the workflows that drive the creative process.

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The recent comment about autonomous cars by Governor Jay Inslee of Washington might just be a slip of the tongue, or it might be an indicator of how confused the American public has become about self-driving vehicles.

Inslee, after signing an executive order allowing automakers to begin testing autonomous cars on his state’s roads, unwisely used the term “foolproof” to describe the technology.

“One thing I know about radar, it doesn’t drive drunk, it doesn’t drive distracted,” Inslee was quoted as saying in the Seattle Times. “We humans are really good at a lot of things, driving cars isn’t necessarily one of them compared to the automated processes that are digital and foolproof.”

Internet publications were quick to pounce on the comment. CNet dutifully noted that the technology was “still far from perfect.” UK’s Register wrote, “We must have missed the bit where code bugs were extinct.” And Jalopnik published a blunt headline advising the Governor to, “Stop Saying Dumb S---.”

But Inslee’s comment probably serves as a good measure of a growing public belief in autonomous cars. We often hear that autonomous cars are already tooling around our roads. We also hear that automakers plan to produce self-driving cars, some with no steering wheels or pedals, by 2020 or 2021. The public hears this because it’s virtually impossible to traverse one daily news cycle without it.

 

In December, GM CEO Mary Barra announced that GM would begin testing self-driving Chevy Bolts on public roads in Michigan. (Source: General Motors Co.)

 

Too often, though, we don’t hear that today’s “self-driving” cars are monitored by drivers with their hands positioned inches from the steering wheel. And we seldom hear that the 2020 cars will operate in limited domains – prescribed areas with favorable weather conditions. In other words, no snow, no ice, no heavy rain. Mostly, though, we don’t hear about the Society of Automotive Engineers (SAE) automated driving levels. And we don’t hear that Level 5 – full automation – is likely still a decade or more away.

In the way that news gets disseminated, there’s little room for such qualifiers. By the time information is compressed, filtered, tweaked and re-packaged, it ends up being a sentence or two on a radio or television broadcast. And that tidbit leaves the impression that in five years we’ll all be sleeping in the back seat of our self-driving cars as we commute to work every morning.

None of this hurts the auto industry, of course. If we’ve learned anything from Tesla’s position as the most valuable US automaker, it’s that hope pays. Tesla lost $889 million in 2015, lost another $675 million in 2016, and posted a fraction of Ford’s and GM’s sales over the last few years, yet its stock price places it at the top of the US auto industry in total valuation. That’s a lesson not lost on the GMs and Fords of the world. It’s all about the future.

To be sure, many Americans are still skeptical about autonomous driving. And many of those non-believers are engineers. An industry analyst who’s a former electronic controls engineer recently told me he doubts the industry’s ability to successfully make an SAE Level 4 car today. “At this stage, I’d be reluctant to ride in a vehicle that had no steering wheel or gas pedal,” he said. “At an absolute minimum, I want a kill switch that I can hit to shut it down.” He said this, despite his belief that automakers will reach Level 5 by the end of the next decade.

His comment is consistent with those of many engineering professionals, especially those who don’t have a stake in the autonomous car market. They understand the breadth and complexity of the engineering challenge, they envision all the potential failure modes in their mind’s eyes, and they’re skeptical. They’re like waiters who won’t eat in a restaurant – they’ve seen what goes on in the kitchen, and they’re having no part of it.

The point here isn’t that autonomous cars aren’t feasible. They are. Impressive new features are rolling out every year, which is why the National Highway Traffic Safety Administration (NHTSA) has mandated automatic emergency braking by 2022. Automatic emergency braking works. It saves lives. But it should be noted that NHTSA hasn’t mandated total autonomy by 2022.

The problem is we’ve reached the point where the hype is galloping past the reality. And it’s partly because the word “autonomous” is losing its meaning. So for clarity’s sake, let’s recap: Today’s “autonomous” cars have drivers; the 2020 versions will operate in limited domains; and SAE Level 5 (real autonomy) is still a decade or more away.

Most important, though, is this: Autonomous cars, even those driven by governors, will never be foolproof.

 

Do you trust autonomous cars? Do you believe they will be successful at any point in the future? Let us know in the comment space below.

 

Senior technical editor Chuck Murray has been writing about technology for 33 years. He joined Design News in 1987, and has covered electronics, automation, fluid power, and auto.

Researchers at Singapore University of Technology & Design (SUTD) along with collaborators at Georgia Tech, have made a breakthrough in the development of 4D printing. 

According to researcher Martin Dunn, who spoke with Design News from Singapore, “4D printing essentially involves printing something in three dimensions, then subjecting it to some kind of environmental stimulus, like heat, or moisture that transforms it into a new shape. It could also be looked at as printing with smart materials and then activating those smart materials in some way.”

They key to this new process is the use of a two-component composite material consisting of an elastomeric hydrogel and a glassy thermoset shape-memory polymer.

This was not the first demonstration of 4D printing utilizing shape-memory polymers, but previous iterations required a training step where, according to Dunn, “you had to train them, usually by heating them, then physically deforming them into their desired shapes.”

This new process utilizes computational models to control the way that the two materials, a stiff and a soft material, are printed into a composite architecture in a way that builds in a certain level of compressive strain. This eliminates the training process. It comes out of the printer ready to use, as soon as it has been exposed to the conditions that initiate the transformation into the desired shape.

Says Dunn, “We control the final shape by both the process conditions to which the printed object is subjected, and its internal architecture.” The softer, elastomeric material is what contains the pre-stress, which relaxes when heated, changing the shape of the structure as it achieves equilibrium.

According to the paper, which appeared in Science Advances,  “Upon heating, the shape memory polymer softens, releases the constraint on the strained elastomer, and allows the object to transform into a new permanent shape, which can then be reprogrammed into multiple subsequent shapes.”

Applications for 4D-printing materials could include things like patient-specific implantable devices, customized instruments, products that are shipped in a flattened or compressed state, or even UAV designed to change the aerodynamic profile on demand.

Working at what he calls, “the intersection of innovative materials, fabrication methods, and design tools,” Dunn’s team uses modeling and simulation to produce design optimization algorithms to formulate how to create these changeable 3D structures. The models are used to “control and design how to lay out the material,” such that the object will take on the desired dimensions when the elastomeric material relaxes, allowing the more rigid thermoset material to release its internal stress and take on the intended configuration. Mechanical properties such as the amount of pre-load remaining after heating can also be controlled. One example is a flat web-like structure that releases when heated into a dome.

Moving forward, Dunn says they are now using their design tools to produce pencil-sized rods that can self-assemble into complex three-dimensional shapes when heated.

Yes, this is one of those silly, simple things you see on the internet and think "Man I've gotta try that." YouTuber MicBergsma shows you what he does "when I don't have goggles with me [but want] to see something under the water:"

Fillets are one of those design features for which there seems to be no middle ground, or at least not one that is widely known. Either a part is devoid of them, and most or all edges are well-defined, or the part's designer decided to take the opposite route, and every single edge and corner is rounded with some size of fillet radius.

Fillets can be useful in the design world, especially when parts are destined for CNC machining, which will be our primary assumption in the following examples. This article will expose the cases in which fillets are a bad idea, a good idea, and absolutely necessary (hint: corner fillets), so you can start tweaking your designs to be more cost-effective and more readily manufacturable.

Where You Don't Need Fillets

Before talking about use cases for fillets, it's easiest to rule out a few places where you don't need them, because too much of something is never a good thing.

3D Printed Parts

Because 3D printing is an additive process, there's no need to design a part assuming a tool will need to move around it and remove material, and a designer has much more freedom to utilize intricate and unusual geometries. Fillets are sometimes added for stress relief in areas of sharp geometry changes, but beyond that, there is little need for them. Pockets and internal features on printed parts can be angular or sharp-cornered, and you can even have cavities that are completely enclosed by surrounding material!

This 3D printed part is beautifully intricate, but would be impossible to machine as-is.

Also, keep in mind that if you'll eventually be moving away from 3D printing towards another process, such as machining, it's essential you start planning for the limitations of that process early on, to save time and money down the road.

Bottom Edges

Filleting the bottom edges of pockets, walls, or boss features can be used to improve aesthetics of a part or add strength to features (by reducing stress concentrations). However, fillets in these locations require the use of a ball endmill and will always make your part more expensive than square-bottomed features. This is because programming such a geometry usually requires 3D machining operations (which take longer to dial in). Also, ball endmills are by nature more fragile than their square counterparts and must machine at a much slower rate.

Unless you're designing a skatepark or avoiding stress concentrations, there is little reason for fillets such as these.

On a related note, filleting the bottom edge of a part will create the need for another fixturing setup, which will also increase a part's production price.

This part is perfectly machinable, but the highlighted fillet on the bottom edge requires the part be flipped over to machine, which adds significant cost at low quantities. Where Fillets Can Be Helpful

This next section will provide a few examples where fillets may come in handy, despite not being needed. Remember, however, that fillets on a CNC part add programming and machine time— and therefore cost.

Cosmetic Face Edges

When designing a part with cosmetic faces, filleting the edges of these areas can be a nice way to give your part the appearance that its faces blend seamlessly together, rather than transitioning harshly.

Edge Softening

Adding fillets can prevent injuries from sharp edges if your parts will be handled frequently, especially if they are cut from metal. It is standard practice for machinists to hand break all sharp edges anyway, so unless you adore perfectly radiused edges, or your parts have ergonomic features with radiused areas, it might be best to refrain from doing this to save a buck or two.

This handle has had its edges filleted to improve ergonomicsPin/Fastener Insertion

Getting a dowel pin to engage with a press fit hole or a fastener to align with its female threaded mate can be tricky if the fit is tight. Usually, a small chamfer (read: bevel) is added around the edge of the hole to aid in insertion, although a fillet can also help if desired.

The fillet on the hole and chamfer on the pin allows for easier assembly. Where fillets are absolutely necessary

This final section explores three cases in which fillets are required in order for a part to be CNC machinable.

Internal Edges Between Vertical Walls

To cut via high-speed rotation, all CNC tooling is round and axially symmetric, so cutting a square corner between two vertical walls is literally impossible. In fact, any edge where two vertical walls meet at an angle less than 180° requires fillet addition. This is the most common piece of DFM feedback we have to give here at Fictiv about parts destined for CNC.

This pocket has all internal edges filleted properly and is perfectly machinable. Internal Edges Between Angled/Organic Surfaces

Similar to the first case in this section, edges between angled or organic surfaces with less than 180° between them also need fillets. If these edges aren't perfectly vertical, they'll be cut with a ball endmill, and the radius of that tool is the smallest fillet size that can be left between the surfaces.

Vertical Wall + Angled/Curved/Organic Surface

In a combination of the first and second cases, you'll need to include fillets when a vertical wall on your part meets with an angled, curved, or organic surface below it. This one can be a bit tricky to reason at first, but if you picture a square or ball endmill cutting flush along a wall, you can visualize how there will always be material remaining between the wall and the surface below, unless that surface is perfectly flat and normal to the tool.

The only way to machine these slopes is to leave material behind at a selected radius size. In this case, 3.2mm fillets are left by a ¼" (3.175mm) ball endmill. Fictiv Standards

Now that you understand the general cases for and against fillet use, there are two main standards to adhere to if you'll be producing parts through the Fictiv platform.

Minimum Fillet Size

The smallest milling tool our vendors stock by default is a 1/32" endmill (square and ball). This is just under 0.8mm in diameter, meaning the smallest fillet it can create is 0.4mm.

Fillet Size vs. Depth of Cut

Endmills come in lengths of standard multiples of their diameter, but there's a limit to the obtainable length, due to tool vibration and chatter past a certain ratio. Material also plays a role here—it is much easier to cut a deep pocket into a plastic than into a harder material, such as steel. What this means for fillets is that they need to be a certain size, depending on how deep a cut is needed to make the feature on which they're included. Fictiv's max depth of cuts are as follows:

Steels: 5X tool diameter (10X fillet size)
Plastics/aluminum: 10X tool diameter (20X fillet size)

Overall, we recommend sticking to 3-5X tool diameter max, to the avoid sticker shock caused by excessive machine time.

Main Takeaways

Hopefully, these pointers have helped clarify the world of fillets for you. Especially in the case of CNC machining, knowing when and when not to use these features is absolutely critical: It can save you time and back-and-forth with your manufacturer, increase part functionality, and result in a much cheaper part overall. Even in cases when you're not currently designing for machining, it's still a good idea to follow these guidelines, in case you ever decide to. Now that you're equipped with the proper knowledge, share it with friends and fillet away!

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This post is provided by Fictiv, the most efficient manufacturing platform for fabricating parts. Powered by a distributed network of highly vetted vendors, the online interface makes it easy for customers to get instant quotes, review manufacturing feedback, and manage orders—all through a single service.

To a certain generation, the Pontiac Trans Am was the muscle car that was the envy of the neighborhood kids. As a performance package for the Firebird, the Trans Am was fast, mean, brawny. It turned heads every time one roared down the block.

'72'74'78'81

Pontiac went bust in '09, and they hadn't made a Firebird since '02 anyway. But a company called Trans Am Depot, started by three friends (Jim Dowling, Tod Warmack and Scott Warmack) has been fixing up old Trans Ams and reselling them since 2006.

At a car show in 2007, the TAD guys ran into designer Kevin Morgan, a Trans Am enthusiast who had produced fanciful renderings of what a resurrected version would look like. TAD subsequently licensed the Trans Am rights and collaborated with Morgan to actually build one.

Today TAD produces several models, starting with brand-new Camaro platforms, stripping them down and fabricating their own design of the bodies, interiors, lights, grills and bumpers. Modern-day engines and mechanicals are swapped in. 

The company has been successful enough that they've now upped their game and are producing an absurdly powerful, 1,000 horsepower Trans Am Super Duty:

All of TAD's cars are built in Tallahassee, Florida. As for how much the Super Duty costs, well, if you have to ask….

See Also:

Pontiac photo retrospective: Every year from 1948 to 1971