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creating a maker oriented science center

We recently completed a conceptual design and programming study for a maker oriented science center in the Mid Atlantic region. Informal education venues, such as science centers and museums, will be increasingly important nodes in a national network for STEM Education (Science, Technology, Engineering and Math). The proposed concept puts hands on activities and making front and center.

Economics of Additive Manufacturing

I’ve written previously about the advantages of digital fabrication and additive manufacturing (3D printing) specifically. But how do the economics for 3 D printing stack up in the real world against conventional manufacturing techniques such as injection molding.

Summarizing 3D printing selling points:

  1. Ability to print shapes and assemblies likely impossible with other methods – such as intricately formed or nested shapes and structures.
  2. Ease of creating custom shaped objects to meet individual parameters – such as ergonomically tailored sports or medical devices.
  3. Ability to manufacture low volume, but high value objects cost effectively by eliminating expensive tooling and molding.

3D printing offers some clear advantages in the instances one and two above. For instance one, when there are no other physically feasible manufacturing options for a particular form, 3D printing is the only choice. Printing simply does what cannot be accomplished by other means.

Instance number two is somewhat similar. A custom formed object/device fits an individual perfectly and will be produced only once or at most a few times for that person. A conventionally injection molded piece might be too expensive, given the high costs of molds. 3D printing has a clear advantage in both these cases. But what about case three – an anticipated low volume run or a situation where it doesn’t make sense to invest in sizable opening inventories?

Let’s look at an example. In two previous posts I described digital fabrication of a moderately complex lamp of my design, using 3D printed plastic and laser cut acrylic parts. The lamp is made of a central hub which holds the electrical socket and has twisted fins that extend to attach laser cut pieces comprising the lamp shade. (see the white finned hub component in the picture below). What would a comparatively low volume conventional, injection molded hub piece cost, versus the 3D printed version?

Fortunately, it’s now possible to get online quotes for both injection molded and 3D printed parts. I used www.IcoMold.com to estimate injection molded hub pieces and www.Shapeways.com for 3D printing estimates.

3D printing vs. injection molding

Total manufacturing costs, for selected quantities from 1 – 75 units are shown above. Costs exclude design and shipping and compare injection molding (red line) and 3D printing (blue line). The major cost with injection molding is the mold, itself, which in this case, costs about $8,500. In a convenient statistical breakoff, manufacturing runs of less than 50 units yield a lower total cost than for 3D printing.  As can be seen, there are few economies of scale in printed parts, aside from perhaps amortizing design and reducing inventory costs. Unlike molding, the 75th part costs as much as to produce as the first unit. Having said this, manufacturing runs greater than 50 may also be cost effective for 3D printing when factoring in inventory/stocking costs.

What does this analysis suggest? Extremely limited volume and custom, one-off, high value parts and products will be increasingly produced with 3D printing. We can also expect that as 3D printing costs decline – as they surely will – more and more spare parts and limited production parts will be fabricated by printing. Another important cost factor not included here is that transportation costs – and carbon footprints – should be reduced. Many injection molded parts are made in China, requiring extended supply chains and logistics which are costly in both financial terms and environmental impact. Printed parts are also easier on cash flows. With greatly reduced upfront manufacturing costs, entrepreneurs can invest in products with less trepidation.

A Longer and More Winding Road to Personal 3D Printing?

A Mixed Bag of Making

I have touted the prospects for digital fabrication and more specifically the economic benefits of the additive manufacturing revolution enabled by 3D printing. Great strides have been made to bring 3D printing out of computer lab and into the R&D shop. Thousands of firms now use printers costing from $15,000 to the millions to create rapid prototypes and finished parts. But beyond the computer lab, hacker space and R&D department how does printing fare when released in the do it yourselfer’s shop?

Options for 3D Printing

While it’s quite easy to print readymade files and use fabbing service bureaus to outsource prints, my preliminary verdict from personal experience and some frustration – is that there is a ways to go yet before personal 3D modeling and printing is simple, effective and ubiquitous. I suggest the situation with 3D printing is a bit like personal computing about 30 years ago and I’ll explain why this is and what’s needed to transform the industry.

First let’s look at the Maker’s options for 3D printing assuming you don’t work in the rapid prototyping industry or a computer or fab lab type of environment that has access to experts, high end software and hardware. Let me also note that you don’t have to be creating your own models and printing them on your own printer to be involved with making. However, many, if not all creative types will at some point want to create and print their own 3D designs, if not in their own office or shop, then somewhere local that may not possess a high level of expertise.

Fabbing Options Now (also see diagram above):

  1. Existing Model Printed at Service Bureau: Find an existing free model on the Internet and send it to a fabrication service like Shapeways or Ponoko (or local fab lab) who will print and ship the finished product back to you in a couple weeks. There are thousands of models available. Presumably as the inventory of models grows there will be ones that meet many aesthetic and functional needs.
  2. Existing Model Printed Locally: As with method above download a freely available model and print it on your own printer or at a community fab lab, where you might get some help.
  3. Create Model and Print with Service Bureau: Create your own design with 3D software and send it off to a local or cloud based service bureau. This assumes your model is valid for printing. Some services like Ponoko and Shapeways are willing to help evaluate and repair a printable file for a modest upcharge or subsciption.
  4. Create Model and Print Locally: Design it and make it on your own studio/shop’s printer. I assume many makers want to do this; personal expression drives making. And this is where things get tricky.

Not Quite a Personal Factory – Yet

Wishing to investigate the personal end of 3D printing I  purchased a fully assembled Makerbot Replicator www.makerbot.com and it was delivered about a month ago. Makerbot has been the poster child for 3D printing and has been featured in dozens of publications and TV shows during the past year. The new Replicator model is a vastly improved over the version I purchased and built from a kit about two and a half years ago. I took the Replicator out of the box and printed a preloaded 3d model file from a supplied SD card in less than an hour. Alternatively, I could have downloaded a free prepared model file from the Internet (www.thingiverse.com) and printed it from the SD card that slides into the Replicator’s SD slot. Once you have a model file you don’t even need a computer to run the Replicator – an on board touch pad and LCD display the necessary menus for printing. This is all pretty easy.

But what if you want to make something of your own design? Curiosity, self expression and problem solving drives creative types and inventors They want to solve a unique need they’ve identified or express their own creativity; not just copy someone else’ model. This is where 3D printing becomes considerably more complicated. Printing a unique, freshly minted 3D design still takes considerable effort and most likely a lot of trial and error.

Is It Like 1982?

I’ve previously suggested that the current status of DIY 3D printing may be like that of the personal computer 30 years ago. In 1982 you could buy an IBM PC or an Apple but it lacked a graphic user interface and a mouse. Word processing software existed in a couple of text only applications such as Wordstar or Wordperfect and Visicalc was the only spreadsheet. Printing was a rudimentary, dot matrix affair. The introduction of the Mac in 1984 began to revolutionize the situation, with graphical user interface, mouse and well integrated word processing and other applications. We know how quickly things changed after that.

The fundamental problem with 3D printing now is that it’s not a simple process to get from the model to a printable file. The model file needs to be translated into a fully closed triangular mesh. Imagine you must represent a solid volume, your model, with many small triangular shaped pieces of paper that are cut and glued together, creating an exterior shell of your solid object or assembly. The resulting construct, called a stereolithography (stl) file, should be a “watertight” model or it can’t be parsed in many thin layers and printed.

The opportunities for holes and other errors not readily apparent to the eye become rapidly clear in such a construct when considering any shape more than a simple box or sphere. And fixing the holes can be a confounding job. I, still, have not been able to create printable files from two models of my existing portfolio, after many iterations and the deployment of a program designed explicitly to find and fix such problems. I expect more research and effort on my part will resolve the problems, but if the personal printing industry is to explode then these problems need to be addressed with innovative products.

What’s Needed

While a number of good 3D modeling applications are available, in both the paid and free categories, none I’ve come across offers a completely smooth and foolproof workflow from model creation to print file generation. Some helper applications offer model file fixes but from my experience, they still overlook issues that turn up when compiling the code (G code) instructions for the 3D printer. There’s no doubt I need to become a better modeler for 3D printing. However, the Maker world of the near future should give me the option of printing my objects as simply as sending this page to the printer.

Factory in a Cloud; Part 2

Fablamp combines 3D printing with 2D laser cut acrylicIn the previous post I outlined the prospect for cloud based do it yourself (DIY) digital manufacturing. I described a test of this capability using the fabrication (fabbing) service, Ponoko, to make the parts for a lamp of my design, using laser cut acrylic sheet and 3D printed polymer. My goal for the project was not to create a production ready consumer product. Instead it was to test a process of prototyping and potential manufacturing, using remote resources. This post picks up on the fabbing process, once my design files had been submitted and accepted by Ponoko.

Delivered Goods:

I received the flat laser cut pieces (purple plastic in the photos) just a week after my order. They met my expectations, with accurate shapes and nearly smooth, polished edges. However, it took almost 3 weeks to receive the 3D printed polymer housing for the LED lamp (the white finned piece in photos). When this part arrived I was reminded that my knowledge of file preparation for fabbing leaves something to be desired. In translating the computer model’s smooth twisted surfaces of the housing “blades” for printing I had over – simplified the file, resulting in faceted rather than smooth curves. This was not my original design intent but on second consideration the faceting creates an interesting texture. The durable polymer material I had chosen has a slightly rough, but not unpleasant, texture. Since I wasn’t certain of the exact attachment point of the flat lamp leaves onto the lamp housing housing I had left the attachment holes off the laser cut pieces; opting instead to measure and drill these holes in my shop. Once drilled, the 1/4 inch holes in the leaves press – fit perfectly over the “buttons” I had cast into the lamp housing. From there, the lamp was easy to assemble and wire.


I now have a lamp prototype that cost about $250 and took 3 weeks to complete, not counting computer modeling. I could not have easily created this object using conventional methods or materials. In theory I could have hand cut and finished the leaves of the lamp on a jigsaw and drill press but this would have taken hours and the accuracy would have been nowhere near perfect. Perhaps I could have carved or molded the central lamp housing out of plaster or polymer clay but this would also have been time consuming and again, the accuracy would not have been good. So, $250 for an accurate, attractive, working prototype is pretty cheap.

Had I been more knowledgeable about computer modeling and file preparation for printing I could have achieved a more finished piece for the lamp housing. Moreover, there is a range of materials available; Ponoko offers smooth, shiny finishes in a variety of colors and materials including ceramic. So, in theory, achieving a consumer ready product is not beyond reach. I should also mention that Ponoko is not the only option for outsourced fabbing; Shapeways offers similar service.


What’s to be learned from this experience, over and above surmounting the technical requirements for making finished parts that exactly match your expectations.

Not Exactly Rapid Prototyping; A three week wait for a prototype is too long. Prototyping usually depends on fast iteration. I may have been able to shop around and find a quicker service but I doubt I could have found one that could have delivered a part in less than a week under $250. By comparison, Makerbot Industry’s new Replicator promises an out of the box 3D Printer for about $2000. If the print quality is near the quality of the part I ordered then about 8 more prints from a fabbing service would be the equivalent of a purchase.

Manufacturing Is a Possibility; Even with a long delivery time certain types of custom goods could be outsourced to a manufacturing platform like Ponoko. Nike’s custom shoe program promises delivery in 3 – 4weeks. A quick scan of Ponoko’s inventory of design offerings by various makers suggests that jewelry, small housewares and home furnishings are popular areas. Can one compete with IKEA or Target on housewares and furnishings; no. However, perhaps more fair comparisons are Design Within Reach and other high end purveyors of artisanal modern home furnishings sold in fairly small quantities.

Additive Manufacturing; Unlike laser cutting or CNC routing which is basically just a faster and more accurate means of cutting or carving away something that can already be done by hand or less automated machines- and these are no small feats – 3D printing allows the making of shapes and assemblies that might be otherwise difficult if not impossible to create. Complex nested geometries that mimic biological structures are possible. Now, people offer elaborate, biomorphic jewelry pieces, printed in materials including precious metals. However, before long printing of human body parts and organs is likely. For now, beyond prototyping, jewelry and luxury furnishings, additive manufacturing favors small quantity, high value parts and assemblies in the medical and aerospace industries. What other niches cry to be filled?

Factory in a Cloud Part 1

Can you design and create a tangible product from your desktop, using cloud based digital manufacturing? The answer so far is yes, but a UPS delivery in the near future will tell for sure.

Large manufacturing companies have employed automation for years. Assembly lines, automated machine tools and robots populate most medium to large manufacturing facilities. Until recently however, this technology hasn’t been readily available to small business or hobbyists – sometimes referred to as makers. Now, digital fabrication has come to the maker masses. Instead of table saws, drill presses and x-acto knives in basement workshops, garages and studios, makers around the world have the choice of either local fab labs or they can outsource their digital designs for making on the Internet. I have opted for the latter to test the digital manufacturing cloud.

Making in the Cloud

How well does the fab – in – the – cloud process work and what are the implications for future design and manufacturing? I will report what I learn as I design and make a test project. I’m using Ponoko as my fabbing portal; a global clearinghouse, where people can design, make, buy and sell things constructed with digital fabrication methods. BTW, what is digital fabrication; it’s several different technologies that use robotics to cut, shape or print two or three dimensional parts using a variety of materials.

The Project

For the test, I want to design and make something that I cannot easily create by hand or by common machine tools. I also want to use more than one fabrication method and material offered by Ponoko. I have chosen a light fixture. Aside from a standard socket and light bulb, there is considerable freedom in the form a lamp can take. It can be almost anything with a bulb and power source. For simplicity sake my lamp design is built around an energy efficient 8 watt LED flood lamp screwed into a US standard (E27 110 volt) socket available from any hardware store.

I’ve decided to create a complex shape for the central lamp housing, printed in 3D. I also determined that the lamp “shade” will be made from several pieces of another laser cut material that will be attached to the central housing by pushing the parts together with tabs and holes.

I started with a few hand drawn sketches and some fast, crude cardboard mockups but it quickly concluded I should be taking full advantage of the tools at my disposal; both digital design apps and the capabilities of 3D printing. I’m moderately proficient with Rhino3D and I could quickly create and visualize more complex shapes than I could readily draw and or hand model with clay. I started with a symmetrical fixture housing and proceeded to make it more complex by twisting the ribs or that would support the individual leaves of the lamp shade.

Not wanting to get overly involved with design – this was a production test after all, not a design competition – I settled on the design shown above. It consists of a housing with twisted ribs containing the LED bulb and wiring connection and 8 snap – on “leaves” made of flat material. The Rhino screen shot below shows the two basic parts of the lamp; the printed housing and the flat leaves

Design evolves to capitalize on 2D laser cut and 3D printed parts

Preparation and Fabbing

Once you have completed a design you upload it. Ponoko provides quite a lot of documentation, including templates and an upload process that validates your design so you know if it can be made according to the fabrication method chosen; e.g. 3D printing, laser cutting, or CNC routing. In my case the lamp housing is 3D printed and the “leaves” are 2D laser cut. For the 3D print I had to export from Rhino as a stereo lithography (stl) file, taking care to make sure I had a “watertight” model with all surfaces closed. This took a fair amount of trial and error. I had to export the pattern for the “leaves” from Rhino and convert it within Illustrator to an .eps file. Pononoko offers a large selection of materials. I could have selected aluminum, sheet acrylic, or several types of thin sheet plywood, including bamboo, but I chose acrylic for the “leaves” and durable (white) plastic for the housing. To make things somewhat more demanding for the laser cutter I created a pattern of elliptical cutouts on the “leaves.” With a little fiddling and online help I was able to upload both files and get immediate feedback that my files were good to fab.

The lamp housing will cost about $270 and the laser cutting about $30. If the finished parts match my quality expectations I consider this a reasonable price for what amounts to a complex prototype. Of course I’ll be interested in the part quality, the fabbing schedule (I don’t know that yet) and how a refined design might improve both cost effectiveness and aesthetics. The larger question is how a service such as Ponoko might figure as a viable business partner in the inevitable transition to digital manufacturing.

Stay tuned for my reports on the finished parts and lessons learned.

Fabbing Our Way to Recovery; Digital Design, Fabrication and the Internet of Things

Several related developments in computing and technology suggest intriguing prospects for the world of design, plus tantalizing opportunities for domestic manufacturing and economic development.

Digital Fabrication

Digital fabrication uses computer controlled tools, such as laser cutters, routers and three dimensional printers to make parts and assemblies. Formerly, such work required expensive molds or cutting and shaping with a variety of tools. Until recently, due to its high cost, this digital technology was mainly available only to large or highly specialized firms in the electronics, aerospace and auto industries. They used it to make prototypes and limited edition, high – value parts.

However, in recent years, the cost of these tools has fallen and they have also become simpler to use. As a consequence, the technology is now available to a broader set of customers, including small businesses and hobbyists. One of the most publicized examples of these digital fabrication tools is the Makerbot, a three dimensional printer that can create small intricately shaped, plastic objects.

Digital fabrication has made ubiquitous inroads in low profile industries as well. Consider your local sign shop or T shirt outfit and it will not surprise if they use digital technology to cut and print some of their products. In many respects the digital fabrication trend has snuck up on us.

Computational Design

Until fairly recently computers were used as automated drafting machines in the world of design and manufacturing. Now they are increasingly employed to model complicated shapes, assemblies and systems and they also simulate a product’s operation. In the construction industry for example, virtual buildings can be designed and assembled using a process and software called Building Information Modeling (BIM).

Three dimensional geometries, more complex than could be imagined and drawn manually, can now be created mathematically and represented with the technique of parametric modeling. Software can visualize a physical design solution such as a complexly curved building wall with operable openings or shutters, simulate its operation, write computer code for an array of sensors and actuators interacting within the prospective wall system and then, in theory at least, output the relevant model information directly to digital fabrication and assembly.

Microcontrollers and Sensors

With the explosion of consumer electronics such as smart phones, computing device size and cost has fallen, while computing power has drastically increased. Miniature computers on chips, known as microcontrollers, the most popular of which is the Arduino, retail for less than 20 dollars. These devices can be programmed using relatively simple computer languages or graphical editors requiring no programming knowledge. They can control sophisticated arrays of sensors and actuators such as lights and motors. Hobbyists, students and researchers have used them to control robots, toys, vehicles, appliances and even building mechanical systems.

Internet of Things

The growing distribution of sensors and actuators has generated a need to connect these things together in controllable networks. Called the Internet of Things, a series of objects, sensors, computers and people can be linked together over the Internet. This offers a pathway for commercial users for example to manage a building or factory including its inventory, or for consumers, the opportunity to manage their homes and all the devices and appliances within them from a smart phone.

From Fab Labs to Fab Manf

Most digital fabrication has until recently been the purview of large businesses, computer science, engineering and architecture schools, T shirt and sign shop examples notwithstanding. Popular interest in this technology has manifested in the creation of what are termed Fab Labs. These Labs are often community workshops, equipped with many of the tools mentioned here and made available to students, hobbyists and small businesses. Hobby interest in what’s called the Maker Movement, has been promoted by Make magazine, a contemporary essay on Popular Mechanics.


What are we to make of these developments? Some in the Maker Movement envision a future where individuals and small groups are empowered to build networks of sophisticated, highly interactive things. These could be buildings, appliances, cars or small, local utility systems. The scale of these endeavors might fall in the market gap between the Fab Lab concept and conventional large manufacturing.

Won’t digital design and fabrication just eliminate more jobs? The answer could be yes and no. Yes, if referring to jobs requiring the hand fabrication of parts and assemblies now made domestically. However, no and even a net gain of jobs, if parts and products now imported can be produced competitively in the US. In theory, with digital fabrication assuming a larger percentage of product price, country differences in labor cost will matter less, making US goods more competitive.

If more parts and products can be manufactured competitively at home this also reduces expenditures in global transportation, not to mention fossil fuel consumption and greenhouse gas emissions; fewer containers making their way across the Pacific from Asian manufacturers. One key to reinvigorating the economy, will be for entrepreneurs to identify specific industries and business models that make the fabbing approach feasible beyond traditional, highly capitalized sectors. What opportunities for fabbing lie ahead in such industries as home furnishings, building products and construction?

the retail end of the smart grid; consumers first!

EnViz Residential Demand Response

The smart grid has been promoted as key to this country’s energy future; an intelligent network tying together power production, transmission, distribution and consumption; reacting in real time, matching supply and demand. At the residential, “retail” end of the smart grid, conventional marketing wisdom has it that a utility installed smart meter will facilitate home energy management as well as responding to system wide peaks through voluntary curtailments, known as Demand Response DR).

Under this rubric, using the smart meter, the utility, with the consumer’s permission, will be able to curtail non essential electrical loads as needed, benefitting the customer with less electric consumption and a smaller electric bill while helping the utility by reducing the need to construct expensive new peak generating capacity or to purchase power off the grid at costly peak rates. Despite considerable corporate marketing efforts and some positive publicity, smart meters have nevertheless experienced consumer resistance, due in part to skepticism of utility motives, ratepayer equity issues, privacy concerns and also what may be a libertarian streak among homeowners who don’t like the idea of a utility telling them when they can do their laundry. Furthermore, the build out of smart meter enabled service areas will at best, take as much as a decade, and even then likely leave out sizeable sectors of residential consumers.

Given this situation, should consumers and other stakeholders with an interest in DR simply bide their time until the smart meter and its associated home management system arrive? Not necessarily. There are other promising routes to residential energy efficiency and demand management. Electric utilities might wish otherwise, but today with multiple communication and control techniques now available, residential electric energy management systems aren’t restricted to pathways running exclusively through the electric meter, such as the smart meter systems described.

We believe DR makes sense, but it also has to put consumers, not the utility, foremost. As an alternative to utility directed demand response, we envision a consumer driven home energy management system. Based on increasingly popular and proven wireless communication protocols, cheap sensors and microcontrollers, such a system could connect and control key residential loads without resort to communications via the electric meter and the utility. Every residential electric consumer in the country can benefit. E2C2 LLC is developing such a solution, known as EnViz. The diagram explains it.

will “seeing” our travel and transactions make us smarter consumers and commuters?

travel and transaction week map

I chatted with a computer scientist colleague last week about an open transaction platform he’d like to build that would bypass the major vendors and give consumers and small merchants alike access to the type of data retail giants now use to sell us even more stuff. One of the benefits of this open platform, among others, would be that we, as consumers, could see current records of our transactions on our handhelds by category. Moreover, I have been thinking, what if we could also place these transactions in geographic space. Would a picture of our goings and purchases make us smarter consumers, and more energy conscious, perhaps. I’ve recently read Richard Thaler and Cass Sunstein’s book, Nudge http://nudges.org/, and have been thinking how some of the precepts of behavioral economics could be applied to more thoughtful energy use.

As a test of the hypothesis that “seeing” a record of transactions and travels might make me more thoughtful about them I logged my commerce and movements here in Washington, DC for part of this past week and built the 3D model of them that you see at left. I think this tells quite a lot about me - perhaps more than I might want a vendor to know. But  it also shows me I could be more considered in my use of transportation. For example, a couple of my car trips could have been accomplished using the subway and walking – but I wanted to save time; the age old conundrum involving time and or money.


The old line goes “Everybody complains about the weather but no one does anything about it.” We’re doing something about this state of affairs. Our art and technology project, called weatherviz, captures and makes visible a small slice of the river of meteorological data that surrounds us.  It is an automated system that downloads weather information from the Internet and uses robotics to drive a large kinetic sculpture. It also animates a constantly – changing computer visualization. The whole production will ultimately be viewable over the Internet.

weatherviz montage

using weather imagery to drive sculpture and computer animation

Weatherviz extends meteorilogical imagery seen on TV and the Internet. It takes weather data and expresses it as movement in a kinetic sculpture.  Weatherviz sculpture and media animations play back interpretations of very recent weather events from a selection of 150 locations monitored by NOAA’s National Weather Service in the territorial United States.

Weatheviz captures and animates four regularly sampled meteorological factors for each geographic locale;  temperature, wind, precipitation and total weather energy. NOAA weather stations span nearly half the globe: west to east, from Guam, in the Pacific, to St. Thomas, Virgin Islands; north to south, from Barrow, Alaska  to San Juan, Puerto Rico.

Demonstrations are slated for later this Summer in Seattle and during the Fall in Washington, DC. When visitors view the outdoor weatherviz sculpture, an electronic crawl accompanying it will identify the weather station and sampling date. Figuring out which components of the sculpture and data visualization match each other for a weather event will be part of the fun and mystery of the installation.

Stay tuned for more weatherviz info as the project reaches the demonstration stage.

the cost of the hoffmeister kink

Does styling matter? The car crazed, including me, can’t have missed a styling trend of the past several years where the bottom line of the rear quarter window in a sedan, coupe, or crossover swoops upward, rather than being more or less parallel with the rest of the side window. This styling device, called a Hoffmeister kink, after its German originator, is most associated with former BMW styling chief Chris Bangle, who introduced it in some BMW models in the early 2000’s.

The Hoffmeister kink, as far as I can tell ,has no function. Instead it just adds an expressionistic flourish to the rear quarter of the vehicle, kind of like tail fins did 50 years ago. More importantly it also magnifies a blind spot in the vehicle by increasing the sheet metal and reducing the glass area. Driving a rented Nissan Murano recently, which featured a massive kink in the rear quarter and almost no rear vision, I started wondering just how many accidents occur because of this styling quirk. I don’t know if  the insurance industry has studied this. Admittedly, a passenger side mirror properly adjusted can eliminate much of the blind spot. But wouldn’t it be easier to simply glance in the rear view mirror to check for traffic without the obstruction imposed by the sheetmetal?

I have generally admired Bangle’s expressionistic approach to vehicle design but the Hoffmeister is not one of his greatest contributions. The shame is that so many other auto makers jumped on the styling bandwagon and even though BMW has pretty much dispensed with this styling touch, it lives on in Mazda, Nissan, Lexus and others, making driving on congested highways all the more difficult. I’m an advocate of good design and this is a reminder that mere styling doesn’t always make the grade.


We develop and market energy efficiency strategies and technologies. We focus on the building and transportation sectors, which account for more than two thirds of the energy budget.