Challenge Winners: 3D4D Dreambox Emergence 3D Printed Sunglasses for Kids

The 3D4D Dreambox Emergence Challenge asked GrabCADrs to develop highly cost effective sunglasses for children as a preventative measure for Pterygium (known in the US as Surfer’s Eye.)

Dreambox 3D Printed Glasses on GrabCAD

Matthew Hayto put together a quick summary that sheds some light on the manufacturing constraints their team and Challenge participants needed to overcome. The winning glasses and the full results are available on the Dreambox Protective Sunglasses for Children Challenge page. Dreambox Emergence was very impressed with the quality, variety and creativity of the 3D4D contest submissions.

We’ve gathered our favorites, but wanted to shed some light on our reasoning, since we know not all entrants had access to a 3D printer to prototype their designs, and printability was one of our deciding factors. - Matthew Hayto, Dreambox Emergence

Fused Deposition Modeling

Most consumer 3D printers use a process called Fused Deposition Modeling or FDM. While this makes additive manufacturing accessible and affordable, there are some serious limitations to the shape of a print such that it is not only possible, but also reliable (our end goal here).


The key to FDM is designing something that can be printed in horizontal Layers. If a layer is larger than the layer below it, the filament has a very difficult time solidifying in place, and will often warp (printing software is able to design in supports to allow for “overhangs” in models, but we’re aiming to use as little of this as possible, since it hasn’t proven as reliable as printing flat models). Because of this, the first model below would print much more effectively than the second, which would require supports along the entire frame to print in place. While the second design is very effective for solving the problem we face with eye irritation in Nebaj, printing it en masse would take significantly more material and post-processing.

Glasses example 1

glasses example 2

Below, we’ve printed the first layer of a set of glasses arms. Since the bottom surface of the model is completely flat (and flush to the build plate), its a simple design for an FDM printer to handle.

glasses example 3


One element of the challenge that was deliberately left open-ended was the hinge portion on a standard pair of glasses. Hinges allow for glasses to be stored safely, with a lower risk of breaking, but are also intricate and challenging to print using FDM technology. We saw 3 main designs:

Snap-in hinges, in which the arms snapped to the frame using a number of variations on small nub and recess joints, proved successful in a number of cases, but ultimately many required a degree of post-processing in order to fit properly, mostly due to the imprecision of FDM printing
Pin hinges, which called for metal pins to be threaded through corresponding holes in the arms and frame were widely successful. The obvious downside here is sourcing pins, since the fewer elements to assembly required, the better for our purposes. We’re investigating further how much of an impact this could ultimately have.
No hinges, many designs featured no hinges at all, and a continuous frame/arm assembly that prints in one piece. While conceptually this is reasonable, printing vertical arms was challenging (see final video).


This design was attractive since it was overall low volume (meaning low cost to manufacture) and very simple (no hinges to complicate assembly). The first video shows the face-down frame assembly in process.

In the second video, the frame is complete and the printer has started on the arms. Because such a small amount of filament is deposited at each end, a systematic drip has started after each one, allowing a second arm to grow out of nowhere. Furthermore, this process is extremely time consuming, since most of the print head’s time is spent in transit, moving from one arm to the other. Another advantage of lay-flat designs is that the print head is almost always depositing filament.


We hope this information helps GrabCADrs and anyone else designing for consumer 3D printing machines build better products. You can view, download and print the glasses that took finalist positions in the Challenge.

  • With all due respect to the “Dreambox 3D4D: Protective Sunglasses for Children” winner, and the jury which elected him. As a professional designer concerned about safety -specially when it comes to children-, I must make a remark about the contest as such. This challenge estates “easy printability” as a main goal, but this is inappropriate when talking about sanitary conditions. Quoting the contest presentation:
    “One prevalent problem for the rural communities of Guatemala is Pterygium (known in the US as Surfer’s Eye) – an eye condition resulting from excessive exposure to ultraviolet light and irritated by dust, smoke and other particulate matter. The condition often results in a benign but painful growth over the surface of the eye. While treatment is available, resurgence is common, and more preventative measures are sorely needed, since exposure to light and irritants starts at a young age”
    In addition to my 30 years of expertise in designing domestic products -including specific designs for children- I have consulted three graduates in Optics and two PhDs in Ophthalmology, and they all agree: this approach is inappropriate. Even though the contest means well, the effect of Ptergium in rural communities of Guatemala cannot be solved with inadequate tools and convenient design approaches. The fact that the winning design -truly remarkable as it is- is not fully ergonomic and doesn’t cover the eye completely, proves that the proposed means of production are not adequate. A flexible material would respond better to the needs of a child, and would also protect the eye better.
    I want to make clear this letter of complaint is not motivated on personal reasons. I accept and respect the jury’s decision to choose other designs rather than mine. But I do speak in the name of other colleagues whom have preferred to remain silent. They feel the same way: they have children and grandchildren, and they would never let them wear these glasses. Would you?
    This is my opinion, hurting as it may be -for that I am sorry-, but I had to express it publicly once the contest had been finished.
    For the stated reasons, dear colleagues of GrabCad, I would encourage you to be more careful with your choosing of challenges in the future -I know you give them a hard thought as it is-. Please do not promote illusive contests such as this one, putting pintability and convenience before everything else. You have created a social site full of caring and supportive people who will not think twice to put their minds and hearts to a well-meaning task such as protecting children from disease, so lead them the right way.
    I hope other colleagues will join me in a pledge to:
    – Invite the promoters of this challenge to give freedom and adequate means to the winner of the “Protective Sunglasses for Children” challenge to redesign his glasses according to better standards of health and safety. And that they make them with the right tools and flexible materials so they adapt comfortably and safely , better suiting the morphological structure of the affected children, and finally help stop this disease everywhere.
    – Suggest that the printers given to the Guatemalan communities may also be fit to create many other domestic products they may need. They are artisans and capable builders and -given the right tools- they could benefit further. Promoters could be sure then that they have made a truly social safe and outstanding contribution.
    Finally, I would like to offer my professional disinterested services to design proposed utensils for the Guatemaltecan community, and I invite other colleagues at GC to do the same. We would never be working too hard for the most needed: all children.
    Thank you.
    Antonio Pinfor

  • Hernán Malleret

    I agree 100% with you Antonio. Children health MUST be in the first place.

  • @Antonio, thank you for your comment, and for your great design submissions. You’ve raised some very good points which we’d definitely like to clarify.

    First and foremost, the goal of this contest is to generate designs, discussion and collaboration that will ultimately result in solving a number of product needs in developing countries, as well as to build a community around this. Because they posed an interesting design problem and we have a good amount of data, eye protection was an attractive first challenge, and GrabCAD was the perfect environment to host it. The winning designs are not finalized production models, and we will be working with the designers and health professionals in order to ultimately provide a safe, effective product.

    To your second point, we are absolutely exploring all fields of potential production (not just eyewear), since our goal is to enable communities to produce a variety of effective and beneficial products locally. We’re working on ways to get the design community involved in this, too, and welcome your own thoughts and ideas at While we’ll be working directly with the winners of this contest, we are always looking for passionate designers who want to create good products for people that need them – this is exactly the type of community and discussion we love to see and want to foster.

    I hope this is helpful, and as always welcome your feedback via e-mail or here on GrabCAD. All the best,

    Matthew Hayto, Product, Dreambox Emergence

  • I am pleased to see that there are brands like DreamBox that are willing to listen to constructive comments from designers here at GrabCad.

    This feedback can be extremely constructive for both sides. Besides, it will transform GrabCad into a powerful and crucial tool for the future of product design and development.

    I have more than 30 years of experience creating sustainable designs, and here at GrabCad I have met lots of highly qualified professionals.

    As a matter of fact, I am putting together a designing team with some of these professionals, each one from a different branch of knowledge. We think that this can be really helpful for both GrabCad and the final client.

    We will be pleased to take part on the development of any kind of product that respects its main purpose, and adjusts the production costs to a minimum.

    I strongly appreciate your explanation.

    We will contact you to provide all our knowledge in order to help creating quality products for the ones who really need them.

    Best regards,

    Antonio Pinfor
    CEO Pinfor™