3D Printed Outdoor Lights in PETG

It’s official – my entire house now uses 3D printed light covers!

If you follow this blog you may have seen some of my previous indoor light covers, featuring a 3D scanned sea urchin shell and a pineapple. Of course, I couldn’t stop with indoor lights, especially since the outdoor wall-mounted lights on my house looked like the cheapest fittings available. They were desperately in need of an upgrade.

Luckily the fitting includes a piece that is easily unscrewed to accommodate standard DIY light covers. A few simple measurements, including the diameter of the fitting and distance of the protruding light bulb, meant that I had everything needed to create my own design in CAD. For this one I decided to use Fusion 360, just to keep my skills up as I’ve done a few projects in Solidworks recently. The only other limitation was the size of the Prusa MK3S+ build volume (250 x 210 x 210mm), as I wanted the light cover to be 3D printable in a single piece.

Putting all of this information in Fusion 360 gave me a starting point, and of course I began experimenting with a few simple ideas. The one that stuck was this collection of lofts that twist in different directions. Not overly complex, just a clean design that is easy to clean (a complex lattice would just invite spiders!) and protects the lightbulb from sun/rain. Because these are mounted quite high on the walls, what I really wanted was a cool effect when you are looking directly up at the light from below – see the top right image.

Something else I experimented with for the first time with this design was 3D printing using PETG filament – specifically, PETG from eSun. Why? Mainly because PETG has good UV stability so should last while out in the elements and sunshine. But what I’ve really enjoyed is how easy it is to print with – no warping, good adhesion to the build platform and no smelly fumes while printing. Happy days! I actually used the default PETG settings in PrusaSlicer and they seem to be dialled in nicely (no surprises really, thanks Prusa). The material also has a translucency, so the light shade has a bit of a glow when the light is on as you can see in the photos. If you’re looking for more details about the material properties and slicing settings for PETG, this article is a good starting point.

And of course, I’m giving this design away for FREE! Download from your favourite 3D file marketplace: Thingiverse, Pinshape, Cults, MyMiniFactory or PrusaPrinters.

Happy 3D printing.

– Posted by James Novak

3D Printing Build Farms

3D printing is a slooooow process. While 3D printing geeks like me can spend hours watching a printer lay down layers of plastic, it often turns manufacturers off who are used to rapid manufacturing process like injection moulding where parts can be pumped out every few seconds. However, there is a way to produce products en masse and it’s called the 3D printing build farm.

Perhaps you’ve already seen images like the ones above – these are well known examples of 3D printing build farms at Ultimaker (left) and Prusa (right) that illustrate what they’re all about: Lots and lots of 3D printers! A 3D printing build farm is basically just a collection of several 3D printers, or many hundreds of 3D printers, that can significantly scale up the production of parts. These can often be networked together as part of a single management system, meaning only a small number of workers are needed to keep an eye on things. The benefit over other mass production technologies is that you still retain the benefits of 3D printing a unique item on every 3D printer, rather than just producing thousands of exactly the same product. Of course, you can also produce thousands of the same part, for example the Prusa build farm is made up of over 500 of their own 3D printers, which are used to print many of the parts to assemble new 3D printers.

A centralised build farm (left) and a decentralised, geographically dispersed build farm (right)

Recently I published a book chapter analysing 3D printing build farms in the context of work and the future. Titled ‘3D Printing Build Farms: The Rise of a Distributed Manufacturing Workforce,’ one of the main opportunities we discuss that has not yet been exploited is for 3D printing build farms to be geographically distributed, rather than centralised within a single facility (illustrated above). If all the 3D printers within the build farm are connected to a central management system, then they do not actually need to be located in the same physical location.

Obviously there are some benefits to having all the machines located together, particularly for maintenance and monitoring. However, there may also be several benefits to distributing the 3D printers domestically or internationally, particularly in light of the COVID-19 pandemic and the longer-term changes we may now enjoy working from home, or at least working in a more decentralised manner:

• 3D printers can be located closer to customers. Centralised 3D printing build farms must still ship products around the world, just like conventional manufacturers, which costs time and money.
• Distributed farms may better suit new flexible working conditions, allowing people to work the hours they want, from a location they want.
• New jobs in regional areas with smart regions connected to smart cities. 3D printers may be distributed in regional areas, as well as cities, reducing the need for people to relocate to overcrowded cities in order to find work.
• Businesses may join forces and utilise shared “nodes” of the 3D printing build farm.

Time will tell if this provides businesses with new advantages, but it is clear that build farms, whether centralised or distributed, are a growing trend with real commercial value. Some of the biggest adopters are in the dental industry, for example SmileDirectClub which uses 49 multi jet fusion 3D printers from HP to manufacture moulds for up to 49,000 clear aligners each day. This is big business, driven by 3D printing and build farm systems.

– Posted by James Novak

3D Printed Pineapple Light

3D printing light covers and lamps are always fun projects, you can’t really go wrong.

Continuing from a previous post where I outlined the process of designing sea urchin light covers for my house, I’ve still been wanting to design another light cover to mix things up so each room isn’t the same. Enter the pineapple light! 🍍

Unlike the previous process of designing the sea urchin light from scratch using a 3D scan, this time I was able to find something on Thingiverse that was almost perfect – this model of a pineapple. The bottom part had a really nice geometric pattern that saved me hours of mucking around in CAD and designing the same thing from scratch. This is one of the things I love about the 3D printing community – the open sharing of 3D models to be remixed (also known as a mashup) just like a song or video into something new and creative. You can read more about remixing in one of my previous tutorials.

Similar to the sea urchin light, all the pineapple needed was to be scaled to the right size, hollowed, given a thickness, and have a neck piece added to connect with the light fitting. This neck piece was directly imported from my previous project in Meshmixer (free CAD software), and both pieces were joined together. Nice and easy!

Just like the sea urchin light, these pineapples were 3D printed on a Prusa i3 MK3S in a natural PLA from eSun – it’s a translucent material which I found from previous experiments to work really well for light covers when given a very light dusting of white spray paint. The painted exterior still allows the light to shine through nicely, but just helps define the form better than the natural finish on its own. If you want to see exactly how this compares to the natural filament on its own, or a pure white PLA, check out my sea urchin light post. This design can also be 3D printed without any support material.

Best of all, you can download my pineapple light cover completely free from Thingiverse, Pinshape, Cults and MyMiniFactory! Just like the original design of the pineapple which helped me in this project, I hope this remix will help you in your own project – even if you don’t have the same size light fitting as me, with a bit of editing in Meshmixer or another CAD program, you can easily modify this design to suit your own needs. Enjoy.

– Posted by James Novak

3D Printed Sea Urchin Light

This project has been a little while in the making and it’s exciting to finally be writing about it. About a year ago I posted about 3D scanning some shells, and as part of the scanning I captured a sea urchin shell. At the time I didn’t know what I’d do with it, but fast forward a year and I’ve found a perfect application; turning the sea urchin shell into ceiling light covers in my house.

In this post I’ll go over the main processes and experiments I went through to get the finished product, but in case you’re just here for the big finale, here’s the link so you can download the final Sea Urchin Light exclusively from my Pinshape account and 3D print as many as you like!

3D Scanning

As explained in further detail in my previous post, I used an EinScan Pro 2X Plus 3D scanner, which included a turntable to automatically capture all angles of the sea urchin shell. This resulted in a full-colour, highly detailed model of the shell, as shown to the right. However, as anyone familiar with 3D scanning will know, this model is just a skin with no thickness or solid geometry, and was just the starting point for the design process.

Design

If you don’t have access to expensive CAD programs, good news; this project was completely designed in free software! I’ve used Autodesk Meshmixer for many of my tutorials and posts, it’s a surprisingly powerful tool and a must for anyone involved in 3D printing. Additionally, it’s quite useful when you are working with 3D scan files, which are typically a mesh like a STL or OBJ. The process took a little time, but has been outlined in 6 basic steps below:

1. Fill any holes and errors in the 3D scanned sea urchin shell. In Meshmixer, this simply involves using the “Inspector” tool under the “Analysis” menu.
2. Scale up the shell to the appropriate size, then use the “Extrusion” tool to thicken the skin into a solid shell. So that the shell would allow a lot of light through, I used a 0.7mm thickness for the overall design.
3. I wanted to create an interesting pattern when the light was turned on, so separated several areas of a copy of the original mesh to be used to create thicker sections. This was a slow process of using the brush selection tool to remove areas, before repeating step 2 with slightly thicker geometry. For this design I ended up with 3 different thicknesses around the shell.
4. To allow the light fitting within the shell, a larger opening was needed at the top. A cylinder was added from the “Meshmix” menu and placed in the centre.
5. By selecting both the shell and the cylinder together, the “Boolean Difference” command became available, subtracting the cylinder section from the shell.
6. Lastly, a neck section measured off the original light fitting was added. I cheated slightly and modelled this in Autodesk Fusion 360 (also free if you’re a student), but you could use Meshmixer – it would just take a bit longer to get accurate measurements. Then the separate parts are joined together using Boolean Union, and the design is finished.

3D Printing

As well as the new design needing to fit the geometry of the existing light fixture, it also needed to fit the build volume of the 3D printer – in this case a Prusa i3 MK3S. As you can see below, the shell is only slightly smaller in the X and Y dimensions than the build plate.

In terms of print settings, I stuck with some pretty typical settings for PLA, including a 0.2mm layer height. Support material is necessary with the light printed with the neck down – this is the best orientation in terms of ensuring the surfaces visible when standing below the light (remember, it is ceiling mounted) are the best. Where support material is removed is always going to be messy, and you wouldn’t want to have these surfaces being the most visible. Overall, this meant that each light took ~32 hours to print.

Material & Finishing

One of the steps that took a bit of experimentation was choosing the right material in order to look good when the light was both on and off. Each of these lights are the main, or only, sources of light in the spaces they are installed, so they need to provide a good amount of light.

As shown above, 3 different materials/finishes were trialled. Initially I began with a Natural PLA from eSUN, which is a bit like frosted glass when printed. While this allowed all the light to escape and illuminate the room, most of the detail was difficult to see in both the on and off settings. It was just like a random glowing blob. I then tried pure white PLA, hoping that the print would be thin enough to allow a reasonable amount of light out. Unfortunately very little light escaped, however, the shadows from the different thicknesses looked excellent, and when the lights was off, it was very clear this was a sea urchin shell. Perhaps this would be a good option for a decorative lamp, but not so good for lighting a whole room.

So the “Goldilocks” solution ended up being in the middle – I 3D printed the shells in the translucent Natural PLA, and then very lightly spray painted the exterior with a matt white paint. Just enough to clearly see that it is a sea urchin shell when the light is off, and translucent enough to allow a lot of light out. Perhaps there is a material/colour of filament that would achieve this with needing to paint, but I didn’t want to have to buy rolls and rolls in order to find it. PETG would be interesting to try, and if you have any other suggestions, please leave them in the comments section.

The Result

To the right are the dimensions of the ceiling light fixture within which the sea urchin light comfortably fits. The light itself is a standard B22 fitting, so the sea urchin can comfortably fit most standard interior lights. However, if you have a different sized fitting, or want to fit it over an existing lamp, you can easily scale the design up or down to suit your needs. I’ve already fitted one of the early small test prints over an old Ikea lamp, it just sits over the top of the existing frame. In total I’ve now installed 5 of the large ceiling light covers in my house, and am planning a new design to replace some of the others (my house is full of this terrible cheap fitting!).

As mentioned at the beginning of this post, I have made this design exclusively available on Pinshape – it’s just a few dollars to download the file, and then you can print as many as you like! If you 3D print one, please share a photo back onto Pinshape, I love seeing where my designs end up and what people do with them.

– Posted by James Novak