On a roll…

Two days ago I finally finished assembling my Filastruder and Filawinder. There were a few last minute tweaks that became necessary once I had decided on my final setup and positioning of the assembly in my studio, such as sourcing a longer cable for the Filawinder sensor and making a stand for the Filastruder to sit on. I had initially planned to go for a fully wall-mounted vertical setup, but the Filastruder is a reasonably heavy piece of kit, and as I don’t quite trust the strength of the walls in my studio, I ended up going with this 45 degree angle tabletop assembly instead, designed to fit the enclosure I am using. Going vertical should always be considered as the superior option, because of the way gravity aids the extrusion process, but you have to work with what you’ve got. Setting up the Filastruder on my workbench and the Filawinder on another workbench opposite gives me enough room between the two machines to drop the filament in a generous loop once extrusion starts, with the Filawinder sensor placed on the floor between them. The sensor cable that was included in the kit was not long enough for this to work (and as 3mm filament needs a slightly longer run before going into the Filawinder, I am guessing it would not be for most people extruding this diameter), but I sourced a 15ft version and the appropriate connectors, which should hopefully see me through all future eventualities.

With everything in place it was finally time to turn on the ‘struder and do the initial purge! Excitement mixed with apprehension as I turned on the heater for the first time and  watched the numbers on the display creep up, eventually reaching the target temperature of 171C. At this point it is really important to give the Filastruder enough time to heat up thoroughly – anyone who has ever used an enamelling kiln will know this as ‘soaking’. While the thermocouple might be displaying the target temperature, this is only measured on a tiny part of the assembly, and it can take anything from an additional 10-30 minutes for that temperature to reach other areas of the machine. Turning on the motor before everything has been thoroughly heated through can lead to disastrous results – in extreme cases even barrel deformation – as the plastic is not liquid enough to let the screw turn freely, putting strain on the motor and other mechanical components. After about 30 minutes I finally felt comfortable enough to turn on the motor. The PLA started shooting out of the barrel almost immediately, initially as very liquid blobs of hot plastic and eventually as filament. During the initial purge, this will be filled with metal particles and other debris, and it could take up to 8 hours to clean out the barrel completely. This gives you however plenty of time to adjust the temperature settings to suit your material, and really fine-tune the diameter of your filament. In my case, it transpired that 171C was far too high for the PLA I am using (Natureworks Ingeo 4043D) and eventually I settled on 155C which gave me a relatively stable output of 2.7-2.8mm filament.

Next: getting the Filawinder to work. 3mm diameter filament poses a further challenge for the winder, as it is a lot stiffer when it comes out of extrusion and thus harder to wind. My initial attempts to get it to work failed miserably, mainly because I had followed the assembly instructions to the letter and cut my length of PTFE tubing in half, making it too short to work in my setup. This resulted in increased strain on the spool which meant the motor was not strong enough to pull the filament and kept getting stuck. Luckily I still had the other bit of the tubing, and a bit of kapton tape later a full length PTFE tube means that the Filawinder is now working like a charm. This is really important for getting a consistent diameter – even moving the sensor during winding can mess up the fragile dynamics that exist between the extruder and winder and be the difference between producing excellent filament and something ready for recycling. After six hours my initial purge was complete and my first spool of filament all wound up:

FirstPLA01Of course, its contents will now be going in the bin as the contaminants mean the material is unsuitable for putting through a 3D printer or re-extrusion, but I’m still proud I made it this far and now have a working setup to extrude my own custom filament. More to follow soon…

Tools, Tools, Tools… part 1

In my quest to make this site somewhat of a resource for budding digital jewellery designers, this post will be about one of my favourite topics: tools. As a jeweller, I am absolutely addicted to nice tools – give me a lovely vintage hammer, an unusually shaped pair of pliers or a set of precision Swiss needlefiles and any birthday/Christmas/anniversary is a great one. Of course, when I started working with electronics this meant that I immediately had an excuse to stock up on a brand new supply of great, sometimes weird looking tools. Here is some advice about what to get that I wish I’d had along the way…

1) Soldering Station – not the right place to save money!

It’s the most essential tool you’re going to get for your electronics work. Scrimping on your soldering iron is just not a good idea – you’re going to do countless joints and maybe even attempt a spot of SMD. You might initially get away with using a cheap, single temperature soldering iron, but as your skills grow so will your expectations of what you might want to be able to adjust on your iron. There are many different models out there and I don’t think I have found my perfect one just yet – but after owning a simple non-adjustable plug-in one (Conrad), a cheapish analogue temperature-adjustable one (Maplin – no numbers were given on the temperature dial, just the categories of low/medium/hot) and a digitally temperature controlled one (Maplin again) I have only started to achieve satisfactory results with the latter. It’s great to be able to adjust the temperature down to within a degree, and it heats up super quickly. It did not break the bank either – it will be a while before I outgrow this one. In electronics, Japanese tools are very highly regarded (in jewellery making too, by the way), and I have recently read somewhere that the Hakko brand is the one to look for if you want to go deluxe, but you’ll have to pay for it (or take a chance on an ebay listing, usually sent from China). On my next trip to Japan (if it ever happens…) I will be flying out light and returning with a suitcase full of lovely components and tools by Hakko. Until then I just discovered that my soldering iron can take the very reasonably priced Hakko tips, and that will have to do. The only other thing I might invest in is a battery powered ultra portable soldering iron, to take to workshops and teaching sessions. Oh, and don’t forget to get one of these brass wire sponge soldering tip cleaners to go with your new iron – the little wet sponge you get included for this purpose is a nightmare and cools your iron down every time you wipe it.

2) Wire Stripper/Crimping Tool

Stripping the plastic casing off a piece wire can be a pain…until you discover this little gadget. Again, some really nifty Japanese ones (the Engineer brand is great) are available on the web and they can be very handy as you can crimp terminals, strip wire and cut screws to length all using a single tool. If you’re going to do a lot of crimping I would recommend getting this tool instead/as well, as the handy ratcheting mechanism will save you from developing repetitive strain injury in the long term and deliver just the right amount of pressure, although it does take some practice to get the hang of it. Working on a small scale means trying to get as little wire mess as possible, and crimping your own terminals is the best way to achieve this.There is an excellent and very detailed tutorial on YouTube explaining some of the different tools and crimping techniques – practice makes perfect! The hardest part must be figuring out and getting all the crimps and terminals you need to do the job at hand…

3) A Breadboard…or three

You want to start prototyping and you want to start now! Well, a breadboard is just what you’ll need. Designed to enable you to fit your components together in test circuits, the choice of breadboards is dazzling.  You can get tiny ones for on-the-go projects in all colours of the rainbow, small ones in a fancy tin, giant ones that hook together to make a mega-breadboard and the standard half-size version you see in all the electronics tutorials. I have been very happy with my breadboard for three years now – it even has some terminals to hook up a bench top power supply, which I initially thought would be mega useful, but have yet to try out! I would definitely recommend getting more than one, as otherwise you’ll be constantly dismantling ‘in-progress’ projects to make room for a new idea. Using a few tiny ones in clusters can also be very useful to keep component groups separated. To start with, one that has labelled rows could be a boon, as it is very easy to get confused what row you’re working in at any one time.

I have put together a suppliers list in the Vault section that I will keep adding to as I find more interesting sources for stuff!

PLA – Faberdashery

PLA (or Polylactic Acid) is a great material to print with on the Ultimaker – in fact I would go as far as to say it is the recommended material to print with, especially if you’re just starting out. It has a lower melting point than ABS, and does in theory not need a heated bed to get good adhesion. It is ecologically sound and made from renewable resources such as corn starch or sugarcane. It comes in a rainbow of colours and some very cool speciality filaments (thermochromic, UV active, glow-in-the-dark and fluorescent to name but a few). It also does not smell as strongly as ABS when printing. You can even shred any failed prints and re-extrude them into beautiful fresh reels of filament if you happen to have a Filastruder.

As a downside, it is not as structurally strong as ABS or Nylon, so if you are making high impact engineering parts it might not be your best choice. Ditto any parts that need to withstand higher temperatures – the glass transition temperature (where it starts to go soft) for PLA is around the 70C mark, meaning if you were going to pour hot water into a receptacle made from PLA it would start to deform – not an ideal scenario. There is also the issue of long term material degradation – it has a limited shelf life, and in time parts printed with it will start to become brittle. I have not yet witnessed this effect personally, so it is not really a deterrent for me. PLA is also quite difficult, if not impossible, to print with an all-metal hotend, as clogs can form as a result of the higher operating temperature. The Ultimaker hotend is not all metal, so very well suited for PLA. Stringing and oozing are also more of an issue with PLA, due to its slightly ‘softer’ texture, but this can easily be countered by adjusting the retraction settings in your slicer software of choice, Cura in my case.

While my Ultimaker came with a reel of Ultimaker PLA, I had already ordered another brand of filament I had read a lot about on the forums. Faberdashery PLA filament is manufactured in the UK, so as green as it gets in terms of carbon footprint through long-distance shipping. It comes in an absolutely vast array of colours and finishes, and even better is sold by the meter with 5m being the minimum quantity you can order of any one colour. For someone like me, who makes very small shapes but wants to experiment with many different colours this is absolutely perfect. I initially ordered two of their sample packs, made up of 10m of 10 different colours, in both opaque and transparent. And what beautiful colours they contained! Here are just a few samples:

Faberdashery Filament in (from left to right): True Lagoon, Space Marine and Princely Purple.
Faberdashery Filament in (from left to right): True Lagoon, Space Marine and Princely Purple.

My aim is to eventually print a Hyperhive Cocoon in each colour I have. Unfortunately, thoughts of such a scientific methodology are easily interrupted by artistic exuberance, and things got the better of me when I started playing with changing the filament colour mid-print:

Faberdashery filament in (left to right and bottom to top): Dark Sapphire, Aurora, Orange Fizz, Punk Star Pink, Orange Fizz, True Lagoon, Dark Sapphire, Orange Fizz and Lemon Drop.
Faberdashery filament in (left to right and bottom to top): Dark Sapphire, Aurora, Orange Fizz, Punk Star Pink, Orange Fizz, True Lagoon, Dark Sapphire, Orange Fizz and Lemon Drop.

Faberdashery also do some very appealing metallics:

Faberdashery filament in (left to right): Space Marine and Mercury Red
Faberdashery filament in (left to right): Space Marine and Mercury Red

I can’t wait to try out all the other very appealing colours on their website!


Printing with Flexible Filament

Since getting my UMO+ up and running I have been building up to trying out flexible filaments. I was so excited about printing flexible structures for my research that even before getting the printer I had ordered several spools of filament from different sources – without really checking whether it would be compatible with the printer! I thought as long as it was the right diameter (between 2.85mm and 3mm) it would surely work.


I cannot emphasise enough that it is really important to understand the limitations of the different types of 3D printers out there. The Ultimaker is a Bowden-type printer – the filament is pushed into the hotend through a 70-80cm long plastic bowden tube by a material feeder mounted to the back of the printer. In other words, there is a distance of about 80cm between the hotend and the feeder. For printing materials such as PLA and ABS this method works well – the filament is stiff and the force of pushing it translates reasonably rapidly, although I have read somewhere that problems with stringing and oozing on more intricate structures are more likely to occur because of a slight delay with retraction. For flexible filament however, the Bowden-type is probably the least suitable type of printer. The filament itself is already quite flexible, and the feeder squishing it forward through the tube causes a slight delay, meaning a lot of people experience underextraction or – even worse – terrible jams. Oh, and forget about retraction on intricate structures! The way forward here is to adjust the flow rate and printing/travel speed – you want to keep the material coming out of the nozzle as a nice steady ooze and then prevent stringing as much as possible by making the nozzle whizz over the print. There is a great flexible filament comparison thread on the Ultimaker forum, which was my starting point before embarking on my first tests.

Anyway, the first flexible filament I road-tested on my printer was the Ultimaker PLA Flexible-White filament that came as part of my original order. I figured that as an ‘official’ filament by Ultimaker it should cause less potential problems than others. It is quite a bit stiffer than the Recreus FilaFlex I tested afterwards, and this means that retraction settings actually work. Some people on the forum recommended putting some oil on the filament prior to printing, but I really really didn’t want to have to take apart my printer again to clean off residue, so just loaded the filament, ramped up the temperature a bit to 230C on my usual settings and hoped for the best. This is the result:

The Hyperhive Cocoon in Ultimaker PLA-Flexible White, printed at 230C
The Hyperhive Cocoon in Ultimaker PLA Flexible-White, printed at 230C

I am really pleased with the quality of this print – if anything stringing is even less of an issue with the flexible PLA than with normal PLA, making for a cleaner print and less tidying up afterwards. However, I was a bit disappointed at first about the flexibility of the shape – having expected something akin to silicone, this felt more like a very stiff rubber gasket. I looked up the shore hardness of the material and at A 92 it is at the harder end of the spectrum.

So, fired up by my initial success, I decided to try the second filament I had ordered – Recreus FilaFlex, in both black and purple. At a shore hardness of A 84, the filament itself felt a lot softer immediately, and was a bit difficult to thread through the Bowden tube and material feeder. There are very detailed printing instructions on the website (including the disclaimer that this filament is not suitable for Bowden-type printers!) and Recreus even sell their own hotend optimised for this type of filament. There appears to be a specifically formulated Bowden FilaFlex in the pipeline, but here I was with two rolls and a sense of reckless abandon. I considered the oil again but decided against it for above reasons. However, after reading various posts on the forums I decided to turn off retraction, and instead ramp up the flow rate to 150%. This was the result:

The Hyperhive Cocoon in FilaFlex Black, printed at 230C and 150% flow rate
The Hyperhive Cocoon in FilaFlex Black, printed at 230C and 150% flow rate

The image above shows the cocoon after I had removed the worst stringing, but the result was not bad at all, especially considering the very pleasing squishiness of the material. In terms of feel, this is definitely a lot more like what I was expecting, but there are clearly still issues with oozing and stringing that would need to be addressed. For comparison, here are some purple FilaFlex shapes I photographed prior to cleaning

FilaFlex Purple
FilaFlex Purple

The middle shape was printed with the retraction turned on – a complete disaster both in terms of stringing and underextrusion. The shape on the right displays the best characteristics, which I achieved by turning up the printing speed to 150 and reducing the flow rate to 130%. These figures still need some fine-tuning, but I was pleased to achieve any type of acceptable results with the FilaFLex at all.

There are still a lot of other flexible filaments to try out there, and these first results are very promising. For my purpose, the Ultimaker Flexible PLA is probably more suitable, but the FilaFlex might be interesting for some more experimental work.

Exotic Filament: FormFutura

Since getting my Ultimaker up and running, I have been avidly researching the most wild and wonderful types of filament to print with. There have been a lot of exciting developments in the unusual FDM (Fused Deposition Modelling) filaments sector recently, and it seems more filaments are getting announced every day on Kickstarter. I am starting this series of posts of some of the ones I am most excited about at the moment, although this list may change in time!

FormFutura Filaments

FormFutura, led by filament whizz Kai Parthy (read all about him in this interview) is responsible for some of the most exciting filaments on the market at the moment. Parthy started out by developing LayWood, a filament to imitate the feel and appearance of wood and LayBrick, developed with mainly architects in mind to create prints with a stone-like appearance and feel. LayBrick is so far the only FormFutura filament on my shelf. It is a mixture of PLA and chalk powder, and prints at a temperature between 165C and 220C, although variations in either direction are probably possible. It is quite heavy and somewhat brittle – I managed to snap the coil twice while inserting it through the bowden tube. This is one of my Hyperhive Cocoons printed in LayBrick:

My first print in Laybrick, the Hyperhive Cocoon at 190C

I love the chalky texture of the surface, and how it makes the cocoon look like a calcified fossil. Check out this extended printing guide on fellow blog Extrudable Me! This material will definitely be used for my work in the future – it is very akin to the texture and feel of the z-corp ceramic material, the qualities of which I’ve always adored.

The only downside is nozzle wear – the UMO’s brass nozzle is no match for the fine ceramic particles, which means over time the nozzle will be ground down and lose definition. This is the case for a lot of exotic filaments and is just something that I might have to accept by keeping a spare nozzle in reserve. Kai Parthy has just announced MoldLay, a filament developed for the lost wax casting process, which I am sure jewellery designers around the world are as excited about as I am! FormFutura also brought to the market porous and felty filaments under the umbrella name PoroLay, which I am dying to try out next for their flexible characteristics. Watch this space!


Nickel Titanium Shape Memory Alloy is one of the more well-known smart materials, being used in all sorts from medical instruments to bendy spectacle frames. Shape Memory Alloys (or SMAs as I will be calling them henceforth) were the material that got me interested in my research area in the first place, back in 2006, when their use was still in its infancy within the Visual and Applied Arts community and the only textbook I could find was so scientifically written that I had only a vague notion of how these materials might be useful in my quest to make Jewellery come alive. When I subsequently arrived at the RCA, full of dreams of exploring these wondrous metals, I was told they would be utterly unsuitable for jewellery use in the way I imagined, and that I shouldn’t waste my time. Disheartened but unconvinced my creative path digressed, but in the back of my mind I always knew I would return to the world of ‘Smart’ eventually.

At the University of Dundee we have the fascinating department of Imaging and Technology at the Ninewells Medical Research centre, where a group of extremely talented researchers spend their days developing new surgical tools for use at the hospital. Needless to say, shape memory alloys play an important part in this task, coiled into tiny springs inside long laproscopes, which in turn are used to get into what were previously thought inaccessible areas of the human body.

On a less serious note, Shape Memory Alloys  have been used in a variety of applied arts projects, a few fun examples of which I came across on youtube recently (more fun to be had here,here and here). At CIMTEC I met the charming Dr Patrick Dyer of the University of Brighton, who has done quite a bit of research into combining SMAs with textile applications – a field that has been far more encouraging in finding a use for SMAs. Having seen the shape-shifting clothes created by Hussein Chalayan in 2007 at his retrospective at the London Design Museum, I think SMAs are as exciting as they come but have been seriously overlooked by jewellery artists thus far. It is time this changed, and hopefully I will be able to contribute to that through my research.