3D Printed Hooks

20180521_3D Print Hook

3D printing really does solve so many problems – previously I’ve replaced a small whisk in a milk frother, produced my own kitesurfing fins, 3D printed locking mechanisms for some stand up paddles, and made numerous enclosures for Arduinos. What did we do before 3D printing?

This is yet another example of the need for a unique part – some hooks to display some work in front of my office, which could attach to some vertical plywood fins without permanent fixings like screws or staples. The plywood is 17mm thick, which was the only dimension needed to create this hook design, and I’ve modelled the arms to be a maximum of 17mm apart, with a 1º draft angle to really hold on to the plywood towards the back of the arms which are less than 17mm apart. This creates a good clamping force on the plywood. They are also designed so that they require no support material when 3D printing, making them fast and efficient to produce.

While it’s quite a unique case, I’ve decided to share the design on Thingiverse, Pinshape and Cults  in case it’s of use to anyone, or even just a good starting point for your own design. You could even try scaling them in width to fit the dimension of your vertical board. Happy printing.

– Posted by James Novak


Ninjaflex Part 3 – Flexion Extruder Upgrade

20180515_Flexion Wanhao

This is the third post in a series about 3D printing with Ninjaflex, which initially began using the stock standard extruder on a Wanhao Duplicator i3 (click here to start at the beginning), before a 3D printed modification was trialled (click here for post 2), and now here we are with a completely upgraded extruder specifically for printing with soft materials.

Pictured above you can see some fancy red anodised components and exposed gears – this is the Flexion HT Extruder, a relatively expensive upgrade (US$179) which is about half the cost of the entire printer itself. It replaces the entire core of a standard single extruder; all that remains from the original is the stepper motor and cooling fans. So why upgrade?

Well as the previous posts discovered, the highly flexible nature of Ninjaflex (shore hardness of 85A) meant that it was difficult for the standard extruder to force down through the hotend and out the nozzle. Imagine taking a length of soft liquorice and trying to push it through a hole that is smaller than the liquorice diameter! As a result, after a few minutes of printing, it was common for the filament to begin looping out the back of the extruder. The Flexion extruder has much tighter tolerances around the filament the entire length it travels, so there is nowhere for the filament to go except down. Also, it has adjustable pressure using the round dial you can see with the knurled detail in the photo above – this means you can apply more force on the soft filament to maintain a strong grip against the stepper motor gear. By rotating the dial, you can quickly scale the pressure back when you change to a rigid filament like PLA, with 4 levels of variation possible and a grub screw to really dial in each setting. The design is completely open, (when it was assembled I initially thought something was missing!), which means you can see the filament and gears, which is great for maintenance and adjustment. And while I haven’t tried yet, according to the Flexion website the nozzle can handle higher temperatures than a standard extruder, up to 290°C, which is great for plastics like nylon and polycarbonate.

The photo at the top right is one of the first 3D prints done to test the abilities of the extruder, taking approximately 4 hours. It looks good from a distance, although there are some small gaps where we started with too much retraction and not enough flow – at this point we are still experimenting with settings to get the best results, currently trying 107% flow, 40mm/s print speed and 1mm retraction. If you are using a Flexion for Ninjaflex and have some reliable settings, I’d love you to post a comment and share them!

– Posted by James Novak

3D Printed Assemblies

20180420_3D Print Moving Assembly

One of the most interesting features of 3D printing is that it’s possible to print multiple parts in their assembled state, reducing the need to bring together a whole range of different pieces and assemble them using screws, snaps, glue etc. While this is normally easier using the Selective Laser Sintering (SLS) process, with a bit of experience and some clever design skills, it’s possible to 3D print moving assemblies on a basic desktop FDM machine.

Pictured above are 2 objects I’ve been wanting to 3D print for a long time as great examples of what can be done with an FDM machine. The first is called an Air Spinner and is free to download from Thingiverse. Due to the tolerances and angles between each part, no support material is needed, and you can literally start spinning each of the pieces straight off the printer, functioning like a gyroscope. A nice quick print, and a great demo piece. Below is a video I found of someone printing and spinning one so you can get the full effect.

The second print pictured to the right is a Planetary Gear Keychain, also free to download from Thingiverse. This one is much more of a test of your printer’s settings, the first time I printed it all of the pieces were completely fused together and impossible to free. Even this print required a knife to separate pieces that formed part of the first layer, with the squished plastic bonding them together as my nozzle was slightly too close to the print plate. This one is remixed from another design on Thingiverse which I recommend you check out for all the instructions to help get the best result, and read how other people achieved successful prints. Here’s a short video to see the planetary gears in action

If you’re looking for some fun prints to share with people, these 2 are very much recommended and relatively quick, although I’m still a very big fan of the Kobayashi fidget cube from one of my previous posts whichis another great assembled object. If you’ve got a favourite 3D printable assembly, leave me a comment/link below and I might add it to my list of things to make!

– Posted by James Novak

Oh That’s Handy – 3D Printed Prosthetic

20180114_e-Nable Prosthetic Hand

If you’ve been paying any attention to 3D printing over recent years, no doubt you’ve seen at least a few 3D printed prosthetics. From the Iron Man prosthetic arm to the prosthetics being 3D printed for our animal friends, 3D printing is ushering in a new generation of low-cost, customisable prosthetics. Perhaps you’ve even seen my build of the fully robotic InMoov hand which has been documented on this blog.

At the extremely affordable end of the spectrum for humans, Enabling the Future (also called e-NABLE) is one of the most well-known names, developing a range of  open source prosthetics since 2013, which can be freely downloaded, printed, assembled and sent off to those in need. As part of my research I have wanted to build one of the e-NABLE hands for a while now to understand more about them, particularly in comparison to the more complex InMoov robot arm. As pictured above, I’ve finally got around to printing the Phoenix v2 hand, which is wrist actuated to open/close the fingers.

When you look at all the details, it really is a clever design which is optimised for 3D printing on a desktop FDM machine, with almost no support material or waste, and tolerances that fit really well together. Anyone with a 3D printer could assemble one of these, most of the non-3D printed parts can be sourced at a local hardware store or found in your shed (screws and fishing line). The instructions are very clear, and there are loads of videos to help demonstrate the assembly process and how some of the technical aspects of the hand work. Because I printed in ABS rather than PLA plastic, the only small hurdle I had was in the thermoforming process of the gauntlet (the bent white piece that mounts to the users arm), which required me using a strip heater in the university workshop. If you find yourself in a similar situation, you can check out the details which were posted in one of my previous posts. However, I recommend using PLA if you have the choice to make this part easier, only requiring some boiling water as demonstrated in this video. In itself, this is a really cool technique that I will use in the future to create stronger parts; you can always learn a lot from 3D printing other people’s designs.

Overall the e-NABLE community really has done a great job in refining this design over the years, and I’m already working on some of my own iterations which will hopefully be fed back into the e-NABLE community in the future. If you’re looking for a project to build and learn from, or potentially getting involved in the community and building hands for people in need, Enabling the Future is definitely worth researching.

– Posted by James Novak

The Meshmixer Mashup: Mashup-Rex!

Tutorial Meshmixer Mashup

The mashup is a favourite technique in the music world that combines two or more songs together into a single song. They might be from completely different eras or genres and when cleverly mashed together, they create a new smash hit. But did you know that creating a 3D printable mashup is just as easy as creating a musical one? Take a bit of File A, mix it with File B, and you now have your own creative design.

Over the last few weeks I’ve been putting together a new tutorial for my friends at Pinshape, which includes my first video tutorial as well as the usual step-by-step process to follow along with. Click here to learn how to mashup STL files in only 10 easy steps using the freely available software Autodesk Meshmixer.

The mashup is often called a Remix in the 3D printing world, and is a great way to build upon other designs and add your own creative touch, or re-purpose a design for a new application. The video tutorial is a real-time look at the process, which with a bit of practice, will have you remixing new designs in a matter of minutes. If you want to follow along, you just need to install Meshmixer on your computer, and download the 2 T-Rex files used in this tutorial which are free on Pinshape:

  1. Low Poly T-Rex by steven_dakh
  2. The T-Rex Skull by harry (we are only using the head piece, not the jaw)


Alongside the tutorial is my latest design, the Mashup-Rex. I have made this available for free on Pinshape, just click here to download the file. Maybe you you will create your own remix of my remix? If you do, or you just 3D print the Mashup-Rex for yourself, please share it on Pinshape to add to the community and see how far the design can go! In the version pictured above I simply used a coffee stain to “age” the skull, similar to my previous print of the Star Wars Deathtrooper. I’m enjoying this simple technique at the moment, although you may like to use a 2-tone print, or go all out with some painted effects.

Happy mixing!

– Posted by James Novak

My First Kickstarter Goes Live!

I don’t normally use my blog to promote or sell anything, but I figure for the launch of my first Kickstarter campaign I can make a small exception! Besides, it’s actually developed from some of my previous posts where I hacked my useless Solidoodle Press 3D printer to draw images and had some fun using a Wii Nunchuck controller to manually move the extruder.

Through the month of January Kickstarter are running the Make 100 Challenge, and I was inspired to set something up quickly that would be a bit of fun for both myself and potential backers. The idea of the challenge is to get something off the ground that is limited to 100 editions, so it’s inspiring to see a lot of new projects that might not normally launch on Kickstarter, many of them quite creative and artistic. That’s where I’ve pitched my Kickstarter – something a bit unusual and creative, yet fitting in with my interests of customization, hacking, digital manufacturing, algorithms, coding, parametric design, CAD… All the fun stuff.

On paper the idea is relatively simple – send me a photograph, I use some software to generate a Picasso-like line drawing, and that drawing gets sent to my hacked Solidoodle Press to be drawn on paper. But hopefully the video shows that the process is a little more complex than that, and quite interesting to watch.

I would love you to take a look, share the link, or if you’re really interested help get this project off the ground with funding levels starting at only $8 for the final eBook compilation. Whatever happens it’s been a great experience to put this campaign together.

– Posted by James Novak

22/1/2017 UPDATE: To thank everyone for your support and reaching the 200% funding milestone, here’s a new short video showing what happens when Robot Picasso draws a cliff-top building.

Robot Picasso also has a new Facebook Page you can follow to keep up to date with the latest developments. Let’s keep the momentum of this campaign and try and get 100 unique drawings!

Repairing 3D Prints with a 3D Pen


It’s been a while since I last played with my 3Doodler Pen to repair a broken 3D print – the results were pretty cool, although it takes some practice to get reasonable results. Check out the post and images here. Some people make pretty amazing sculptures with the pen, however I find the real value in using the pen to fill gaps created by warped 3D prints and fix other cosmetic problems.

One of my latest projects is assembled from 16 separate pieces printed on my Cocoon Create 3D printer (60 hours worth of printing!), and inevitably with such large pieces printed using desktop FDM technology, there are some gaps caused by print warping. Most of them are reasonably small, but some like the ones shown above and below are quite large. Unfortunately the 3Doodler uses 3mm filament, meaning that I couldn’t use the same 1.75mm filament used to print the parts to begin with, but given that this project doesn’t need to be cosmetically pretty (prototype only), a different shade of yellow that came in the box will do.


The first step is of course to use the pen to extrude material into the cavity, ensuring to move slowly and use the hot nozzle to bond the new plastic with the original. It can get a bit messy and smelly (do it in a well ventilated area – I had a fan blowing to keep a lot of the fumes moving away, but there were times my eyes were stinging), and as shown in image 2 above, might look a bit rough, but that’s OK. You can go back over some of the rough patches using the side of the hot nozzle to try and smooth them out, not extruding any material but using the nozzle like a hot rolling pin. This technique is also great for blending some of the sharp edges or smaller gaps that don’t really need to be filled. The final step is to use a metal file to clean things up, giving a much smoother finish.

Admittedly this process wasn’t all smooth sailing, my 3Doodler kept getting clogged despite me taking it apart and cleaning it out – I have a feeling it might be the material quality and/or the temperature of the nozzle not being quite as hot as it needs to be, so a lot of time was wasted trying to manually push the filament through the pen and get a steady flow. I did notice that when I pushed the hot nozzle into my original print (the darker yellow plastic) it melted much quicker than the 3Doodler filament, despite them both being ABS. So material quality is likely the cause. But the final result is worth the pain, gaps are cleaned up nicely and the surface is nice and smooth. Time for some testing!

– Posted by James Novak

InMoov Comes to Life

Look! It’s moving. It’s alive. It’s alive… It’s alive, it’s moving, it’s alive, it’s alive, it’s alive, it’s alive, IT’S ALIVE! – Frankenstein.

Yes finally the InMoov robot arm I’ve been slowly printing and assembling is complete and functioning with only the occasional little hiccup. I thought I was really close in my last post where I had assembled all the 3D prints and electronics, but it is definitely the last 10% that takes the most work.

Tensioning the braided lines just right and tying them to the servo’s is a painstaking task, especially in the heatwave we’ve been having in Australia, where you’re trying to resist the urge to wipe sweat from your face while you tie the knot just right… I felt a bit like a surgeon out in a humid jungle performing emergency surgery. A few little broken bits along the way as well from prints splitting or glue not holding, so it’s a relief to finally iron out all the kinks and start playing with the controls.

As you’ll see in the video, I’m using Grasshopper (plugin for Rhino) with the addition of Firefly to control the hand movements at the moment – if you’ve followed my blog for a while you’ve seen multiple demo’s of this software and why I think it’s so good, so I won’t bore you here (if you’re interested check out my project which was displayed at Design Philadelphia 2015). But it basically means I can manually adjust the servo’s in real-time using a simple slider for each finger, or connect fingers to the one slider to control them all at once and create a fist for example. It really makes those final tweaks to the servos easy.

I hope you enjoy seeing this arm come to life – it’s quite inspiring when you see it in real life, especially if you’re familiar with 3D printing and the time it takes just to print all of these parts. Now I can finally start modifying this project and experimenting with the controls, the build is only just the beginning for this robot.

– Posted by James Novak