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

Vacuum Forming Over 3D Prints

3D printing is awesome for creating so many things – I’ve certainly lost track of how many things I’ve made and shared on this blog! But it’s also fantastic to use alongside traditional manufacturing techniques – moulds for casting, jigs to help in assembly, or in this case, as moulds for vacuum forming. The short video above shows this process being demonstrated to the Intro to 3D Printing class at my university. The faces are 3D printed from 3D scans in ABS plastic, and we are using 1.2mm PETG plastic for the vacuum forms.


The results are really detailed – even the layers from the FDM process have been transferred to the vacuum forms as a texture! After a few of these being created some visible melting of the prints was visible, mostly on the chin and nose where the initial contact with the hot PETG sheet is made – so I’m not sure how long they would last if you were to make 100 of these or more. But a great example of how quickly and easily you can create many copies of a part using the relatively simple method of vacuum forming – you could probably create one of these every 2 minutes, with the plastic only needing 23 seconds to heat before the vacuum process. I know I’ve got some ideas from seeing this.

– Posted by James Novak

InMoov Robot Hand First Prints

20160812_InMoov 3D Prints

If you’re already following my Instagram you’ve had a sneak peek at one of my side projects – to build the arm/hand for the InMoov robot. No small project! InMoov is the world’s first open-source 3D printable life-size robot, and you can find some excellent instructions and all the files on the InMoov website, a fantastic credit to Gael Langevin the creator of this robot.

Above you can see the first 3D prints I’ve completed for the arm, all printable even on the small print bed of the UP Plus 2. Some of the prints are also done on my Cocoon Create. At a guess it’s taken about 25-30 hours of print time to get the parts shown above, and there are still plenty more to go, so this isn’t a project for the feint of heart. But it is a great challenge that combines 3D printing with electronics and some understanding of mechanics, like an advanced version of Lego.

20160814 InMoov Details

There are other similar open-source projects out there, such as Open Bionics or e-NABLE, but I chose the InMoov because the instructions seem really clear and detailed (very important for a build like this!), and there is a good level of complexity in the movements of the hand. Check out this video to see some of the movements. Hopefully once I get the hand up and running I can have a play around with the design and the method of controlling the hand, but for now it’s just about getting the hand built and working. Keep an eye out for the progress, hopefully with some of the electronics installed once the servo’s arrive from China.

– Posted by James Novak

Goodbye 3D Printing, Hello 4D Printing

Many people I talk to at events and workshops are only just catching on to this whole 3D printing thing, but did you know some of the exciting research in this field has already moved on to the next dimension – literally?

4D printing might sound a bit weird and wacky, but it basically just means something that has been 3D printed, but changes its shape afterwards since time is the fourth dimension. So a 3D print that changes over time. Skylar Tibbits from MIT is really one of the pioneers of such a concept, so if you want to wrap your head around the concept this link to his Self-Assembly Lab at MIT will have some more videos to explain what it means. Having spent some time lately writing about 4D printing for part of my PhD, I thought it was time to give it a go, taking inspiration from the Active Shoes created by the Self-Assembly Lab.

As you can see from my very rough video, it’s actually quite easy to do. All I did was create a few concentric circles in CAD with a 0.2mm thickness so that they would print only 1 layer thick on my Cocoon Create 3D printer. I then stretched some material (from an old pair of stockings – not mine I swear!) over the base plate and held it in place with clips. A slight adjustment to the height of the base plate to make room for this material and 1 minute later it was done.

20160628_4D Print

The result is really cool (I think) for something that only took 1 minute to print. It’s certainly not perfect, but shows a lot of opportunity for the future of fashion design. If you wanted to only use 3D printing to create this shape it would easily take 20 minutes or more on a standard FDM printer, so I think some more experimentation is required.

– Posted by James Novak

Drawing in 3D – First Attempt

20160514_3Doodler Pen

If you follow 3D printing at all, chances are you’ve at least heard about 3D printing pens like the 3Doodler and others, with the 3Doodler originally funded through Kickstarter and now a successful brand. While I’ve seen people make some really interesting things like the Eiffel Tower and Golden Gate Bridge, I have to admit the pens have never really interested me. I can see the fun for kids because they are so easy to pick up and begin using, much like a hot glue gun, and there are templates you literally trace over to construct your object. However the models are really only visual, it would be almost impossible to make anything accurate or functional in the same way you can with an actual 3D printer.

However I was given a 3Doodler, and have been looking for an excuse to try it out. Well, one broken 3D print off my Cocoon Create (who by the way have their own 3D Pen which was sold through Aldi for $79) and I finally had my chance! The benefit I see of such pens is the ability to repair and weld details on a regular 3D printed part – in this case a Voronoi Tealight Candle Holder available on Thingiverse. You can see the before and after photos above.

I have to admit the process wasn’t nearly as easy as I thought. The slowest speed of the pen is still quite fast, and once the plastic starts coming out of the nozzle you really need to get moving! The easiest repairs were the little ones near the bottom of the design, just a quick squirt and it was done. The larger distances were much more messy because of the speed of extrusion, but adhere well to the existing design especially if you use the nozzle to melt some of it to begin with and fuse the new material. I found that once I had roughed out the repair, I could use the hot nozzle to go back and “smooth” the outside surfaces like putty (although the result is far from smooth). This could be further improved with acetone (you can see some of my previous experiments cleaning surfaces with acetone here) but for an experiment like this, I’m happy to leave it as is.

The kit comes with both ABS and PLA filaments, with 2 temperature settings on the pen to match. However it would definitely be interesting to experiment with some different materials – I see on the 3Doodler website they also sell a Flexy Material in numerous colours. I wonder if you could put a conductive filament through to draw electronic circuits? Hmm that’s not a bad idea, perhaps there is more use to this pen than I first thought…

– Posted by James Novak

Wii Nunchuk Controls 3D Printer

Yes it’s as simple as the title says; I can now control the movements of my useless Solidoodle Press (and probably almost any other 3D printer) using a Wii Nunchuk!

Don’t ask me why. It’s more of a personal challenge to see if it could be done, and now that it can, I have a few fun ideas for this. The whole thing was surprisingly simple, and builds upon some previous work where I used Wii Nunchuk’s to customise a 3D CAD model, and of course my work using Rhino CAD software combined with the Grasshopper and Firefly plug-ins. In simple terms, I’ve managed to convert the X and Y signals from the Wii Nunchuk’s joystick into the X and Y G-code commands used by most 3D printers. It’s a little clunky, but at the same time it’s pretty cool to directly control this machine.

With a couple of buttons on the front of the Wii Nunchuk it won’t be hard to add some extra functionality to this, although my intention is certainly not to try printing plastic using this controller, there’s just no real reason to. You will just have to check back in later to see where this experiment goes!

– Posted by James Novak

Parametric CAD Model with Arduino + Wii

As discussed in a recent post about generative design, I’ve been working on an interactive, generative CAD model to be exhibited at Design Philadelphia, in the Crane Arts Center. Well here is a preview of the [nearly] complete CAD model created using Grasshopper and Firefly within Rhino. Using 2 Wii Nunchuck controllers, 2 people can work together to customise the design of a 3D printable light cover in the form of a lightbulb – in essence, CAD modelling has been turned into a game that requires no instruction and is learned through play.

The biggest challenge with this has been getting the signal out of the Wii controllers. While Firefly has built-in Wii Nunchuck compatability, unfortunately I learned the hard way that it is only compatible with genuine Nintendo Wii Nunchuck’s – and I already bought 3rd party ones off Ebay for a fraction of the price. For some reason 3rd party controllers use a slightly different signal/code, and while the Wii console has no problems with this, the Arduino code is a little more particular. Thankfully after an entire day of messing around, ripping apart controllers, tweaking code and swearing, I managed to find a way in! I had to modify some Arduino code and also use the Serial Read tool in Firefly, running the Arduino IDE in the background and listening in to the readings.

As mentioned in the video I am 3D printing 6 examples of what these outputs look like in real life – this model is not just for fun, it is actually designed to create real products suitable for 3D printing, based off a previous design of mine for a Shattered Faceted Lightbulb which you can download for free on both Pinshape and Thingiverse.

Stay tuned for a look at these 6 prints, which have been printing for the last 94 hours on a Fortus 250mc 3D printer. Yes, 94 hours!

– Posted by James Novak

A Game of Generative Design

150824 Lightbulb

A few weeks ago I designed a 3D printable light cover (lampshade) inspired by a shattered lightbulb – you can read more about it and download the STL file for free by clicking here. I’ve been taking the concept a bit further using Grasshopper in Rhino to explore the ability to generatively create endless forms within the exact same bounds, meaning every iteration can be successfully 3D printed. Above are some of the outputs from this experimentation.

These are going to be 3D printed for an upcoming exhibition at Design Philadelphia, along with the complete interactive CAD model which will allow 2 people to work together to customise the lamp design using Wii game controllers, turning the design process into a game-like experience. There’s a bit of work left to go to get this interactive element right, but it will hopefully show how CAD may move from being a complex, time-consuming skill to learn into something much more tactile and interactive for the every-day consumer. There are already a handful of interesting apps surfacing such as the Shape Maker tool from Makerbot, or the 2D to 3D tool from Shapeways, which make creating 3D files as simple as drawing a sketch on paper and taking a photo. But generative tools like I’m working on may be the next generation, allowing far more intricate and complex forms.

What do you think would be useful for non-designers to create 3D CAD files?

– Posted by James Novak

Grasshopper + Firefly = Light Sensor Prototype

It’s been a little while since I posted any of my experiments using Rhino + Grasshopper + Firefly with an Arduino – but that doesn’t mean I haven’t been busy behind the scenes continuing to experiment! The last video I posted was actually the first showing how it can all come together, and it’s definitely come a long way since then. Time for something new.

This video shows the latest experiment to control the opening of some panels using a light sensor. While relatively self explanatory, the idea is that as more light is detected, the panels open, like a flower opening as the sun rises. This is a very rough prototype to simply test how the system would work and prove an idea I’ve had in my head for a week now. I’d call this a success!

There’s something fulfilling about hacking together a proof-of-concept model like this – it doesn’t have to be pretty, but gets the idea out of your head in the shortest amount of time so you can be confident developing it further, rather than investing a lot of time into a really nice (potentially 3D printed) model that might not even work. With this I can now move on to thinking through both the application and detailing of the concept into more of a product. If you’re interested in finding out more about how this system works, check out the Firefly website. It’s definitely the coolest bit of CAD software I’ve come across lately.

– Posted by James Novak

2D for a Change

2015-06-30 Laser Cut

As a departure from my usual 3D printing talk today’s post is going a little 2D, featuring laser cutting. As part of my PhD research I’ve been playing around with all sorts of sensors, Arduino, Rhino, Grasshopper… and plenty more (you can check out the last post here). One of my latest experiments needs a box to mount some sensors inside, so forming a custom box with mounting holes seemed a great excuse to think a little 2D for a change.

The pieces were designed in Solidworks, and only 2 unique pieces were really required – the main length and the end piece. These were just copied and tweaked to form the slight variations. There’s something nice about the concept of combining the natural timber with some high-tech sensors, so 3.5mm plywood was chosen as the best material. The dimensions I used were to make optimum use of the sheet size with minimum waste, as you can see in the first image. Overall the cutting of all pieces wouldn’t have taken more than 10 minutes, and while the laser didn’t always cut completely through the sheets, it was nothing a bit of brute force and a file couldn’t fix. There’s also a slight bow in a couple of the pieces, so gluing them to form the box might be a little tricky – I’m hoping a few small nails might do the trick without splitting the laminated veneers apart. I’ll add some photos of the final result when it’s complete.

– Posted by James Novak