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…


This week I finally got the shipping confirmation for my Filastruder kit. After a bit of wrestling with Parcelforce and paying the appropriate customs charges (don’t get caught out by these if you order stuff from the US – at the very least you’ll have to pay UK VAT!), I finally took my little brick of a parcel home. Unfortunately, it could really not have arrived at a worse time for me – between speaking at the Handmade by Machines symposium last Friday and giving a paper at XcoaX 2015 next week. So, having no time to put the ‘Struder together for another week at least, I thought I’d do a small ‘unboxing’ photoshoot to get it out of my system and inspect the contents of the package in eager anticipation…


It might not look it, but this parcel packs a real punch in terms of its contents…


…most of which I have yet to identify. Most intriguing bit spotted so far: a huge drill bit that has been filed down in order to create the internal lead screw of the extruder.


And here are the contents laid out in all their glory. I ordered the whole enchillada, so what you see here are the both the Filastruder and Filawinder in bits, as well as a complementary pound of ABS pellets. I have already procured 12.5kg of PLA pellets for my research, and I can’t wait to feed these to the ‘Struder.

Another thing I was able to fit in between writing my paper for next week and doing the unboxing was to start printing the additional parts required to make the kit work. There are various ways to set up the Filastruder, and the design of the hopper depends on the way you decide to orient the extruder. My studio is starting to burst at the seams (especially since the Ultimaker entered my life) but luckily there is still a tiny bit of suitable wall space at the back, so I decided to print a vertical hopper mount that takes 2L bottles as hoppers from Thingiverse.


I chose ABS and 100% fill, as this part comes under a lot of strain and needs to be able to take quite a bit of weight – it might have been total overkill, but better safe than sorry. Can’t wait to put it all together…watch this space!

Enter the Filastruder…

So, my birthday has been and gone for another year. Knee-deep in my various PhD research projects, my parents asked me what I would like for a present this year to cheer me up in these stressful times. Imagine their faces when I told them that I would love a kit to build my own plastic filament extruder – probably not quite what they had in mind!

I first read about the Filastruder on Kickstarter about a year ago, before I even owned a 3D printer, and thought it looked really intriguing if a little dangerous. Kickstarter is a great way of finding out about brand new things happening in the 3D printing community, but even though I have been known to back the odd project or two, and so far have not been too unlucky (if you don’t count the month-long delays – Kickstarter is definitely for the VERY patient), most things presented there should be taken with a pinch of salt. Even vastly successful projects like the Form1 often benefit from a period of beta testing, and if your priority is reliability rather than ‘being first’ it often pays to wait a year or two for the technology to get more established and for kinks to be ironed out.

As I have started to experiment a lot more with my printer recently, two things have come to my attention. Firstly, even though PLA is not terribly expensive to buy, the cost soon adds up as I found myself going through filament at a scary rate in the first few months, especially printing out vital components for my research. Secondly, the amount of waste filament also builds up relatively quickly, either from support material or failed prints, which even despite careful planning can and do happen. So, enter the Filastruder. A relatively simple contraption, it is a build-it-yourself plastic filament extruder sold in kit form by the original Kickstarter developers in the US. Since its Kickstarter days, the kit has built up a solid following of DIY filament makers, with some, such as avid blogger Grayson Galisky,  documenting in great detail their filament making experiments on the Solidoodle 3D Printing Community. Of course, since the Kickstarter campaign other filament extruders such as the Filabot and more recently the Protocycler have come to the market – and I am definitely keeping an eye out for the latter. For a UK based option, the Strooder looks promising – compared to the earlier kits those newer machines are definitely heading away from the DIY aesthetic towards a more consumer-friendly look. But for the moment, the Filastruder is the most economical option actually available on the market (the Protocycler and Strooder are both still in their pre-sales phases with release dates estimated for late 2015/early 2016). I have also opted for the spooling kit, as I have run into tangles with loose filament in the past, and the spooler makes the whole assembly much neater altogether.

Making virgin filament is relatively straightforward – buy PLA or ABS pellets or powder in bulk, add a carefully calculated amount of ‘masterbatch’ colourant to the pellets in the hopper of the extruder, mix and start extruding! The pellets need to be completely dessicated to get a great batch of filament, so baking them in an oven for a few hours will really improve quality levels (and of course storing them correctly afterwards). The masterbatch colourant is either sold with the pellets (Colourfabb do this) or you can devise your own methods to make it up – as far as I can tell from the forums almost anything goes, including the addition of powdered metals, wood etc to make exotic filaments. The possibilities that await!!! And it is a lot cheaper than buying ready-made filament. Depending on where you get the raw materials, you could save between 50%-80%.

However, another major appeal for a lot of people will be recycling their failed prints into freshly extruded brand new filament. And this is unfortunately a lot more complicated. The main hurdle to this is really getting your failed prints and waste filament to become tiny granules again – to work in the Filastruder, they need to be less than 5mm in diameter. Plastic can be a really awkward material to work with, and anyone who has ever tried to polish acrylic will know that using powertools of any kind will lead to rapid melting of the material. So apparently will putting PLA in a food processor to chop it up. Industrial plastic granulators are not only prohibitively expensive, but also incredibly bulky – unless you have a massive garage or outbuilding and get really lucky on ebay or a used industrial equipment auction, this will not be an option for you. The second option is using a special plastic shredder. Filabot last year announced the development of their own mini shredder, the Filabot Reclaimer, which looked absolutely lethal in their original promo video and has since been revised to be operated with a hand crank. Within the EU, there is FilaMaker, with their hand cranked mini shredders which look amazingly robust but are expensively handmade to order. These are probably the only viable options for 3D printing enthusiasts at this point – the Protocycler promises to feature its own built-in mini shredder, which would be a massive boon, but who knows if it is still around in a year? If you live in a city with a large industrial base, you might be able to find someone who is willing to let you granulate your waste PLA/ABS. But failing that, it’s really a question I have no answer for as of yet.

Anyway, I will write updates about my new toy as and when it arrives…


My 3D Hub is online – Geotronic Collective

When I got my Ultimaker, a little card fell out of the package, advertising a website for 3D printing enthusiasts called 3D Hubs. Here, individuals can list their 3D printers and take orders to print out parts for others in their city. The customer uploads their model through the website, and the hub in return for a reasonable fee prints the model within a specified time frame. I think this is a brilliant idea, especially as it can often take weeks to get something printed from one of the main printing bureaus. As a student or hobbyist, sometimes all you want is a quick prototype for visualising what your model would look like in real life, working to impossible seeming deadlines.

So, I decided to set up my own Hub – Geotronic Collective – and I am pleased to say so far my experience has been very positive. I have just finished my first two orders, and hopefully made two customers very happy. It has been an interesting experience for me too, printing two things that are so very different from my own work, each pushing the limits of what the UMO+ can achieve in terms of print quality and especially fine detail. Here is a print of a Fantasy Creature I did for digital artist Agneta Miskiv:

Printed with 0.1mm layer height in Faberdashery Storm Grey PLA
Printed with 0.1mm layer height in Faberdashery Storm Grey PLA

Initially I was worried about the very fine detail features of this print snapping off, especially the fingers and spikes on the back of the head. Because of the complexity of the model, I decided against using Cura to generate the support structures, and instead used open-source software Meshmixer, which is particularly good at creating custom supports. This is one thing that has been bothering me about Cura – not being able to edit support structures at the slicing stage, and instead having to rely on the software to get it right. In Meshmixer, there are a lot of adjustable parameters as well as custom profiles, then the software suggests a network of supports that can also be amended by the user as they see fit. A perfect combination between automation and control. There is a great tutorial on how to use Meshmixer on blog Extrudable Me, as unfortunately the documentation it comes with is not particularly helpful. I have found that sometimes the support suggested by the program can be a bit overkill, but the structures snap off very easily, often in one piece, which is a big advantage for delicate prints in particular. Hopefully more orders will come my way soon so I can continue my adventures in 3D printerland!

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!