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


Ninjaflex Extruder Mod – Fail

20180409_Ninjaflex Mod

This is a short little update following on from my last post attempting to 3D print with Ninjaflex filament (soft TPU):

After limited success using the stock extruder on a Wanhao Duplicator i3, I found a 3D printable Extruder Drive Block on Thingiverse to supposedly help stop the filament from finding its way out out the back rather than being forced down into the nozzle. Well, as you can see from the photos, it looks like it fits quite well, although I did have to slice and file a few areas to fit properly – most notably around the shaft of the stepper motor which was far too tight and stopped it from turning, and the wheel that pushes the filament against the stepper gear which was blocked from putting any force against the filament so did not drive it down into the nozzle. Admittedly, the file on Thingiverse was designed for the Duplicator 4, so it was a bit of a long shot to work with the i3.

So back to the drawing board I’m afraid for Ninjaflex printing – perhaps time to upgrade to a Flexion extruder, or look at some other TPU materials that might be slightly stiffer and more suitable for this basic extruder. Flexible PLA looks interesting. If you’ve had any successes 3D printing with Ninjaflex on a printer like the Duplicator i3, leave me a comment 🙂

– Posted by James Novak

3D Printed Ninjaflex – First Test

20180406_Ninjaflex Wanhao

I’m sure if you’ve been 3D printing for even a short time, you’ve heard of Ninjaflex – a brand of flexible filament for your FDM printer that has rubber-like properties, rather than the usual rigid plastic parts that are more common with ABS or PLA filaments. While I’ve known about them for many years, I’ve never risked clogging my printer after hearing some bad experiences with these softer materials. Until this week!

I’m currently working with fashion postdoctoral researcher Mark Liu, who purchased a Wanhao Duplicator i3 v2.1 for some of our research – not coincidentally, it’s identical to my home Cocoon Create 3D printer. We decided to give the Ninjaflex a go to see if it would print, and if so, what sort of quality we could get since the printer and replacement parts are cheap if we really screwed up! Photographed above is one of our first successful prints, although the truth is we had quite a few failed attempts getting to this point as we experimented with settings and carefully watched each print. The primary settings we are using for these first tests (based off the recommended settings for Ninjaflex which are available in the Printing Guidelines) are:

  • Extruder Temperature: 230°C
  • Build Plate Temperature: 40°C
  • Print Speed: 15mm/s
  • Layer height: 0.2mm
  • Retraction: 5mm (I think this is too much and we will try 0mm or 1mm)

These may not be perfect yet, and I’m keen for anyone’s feedback on what’s led to more successful prints with these soft filaments. The main thing we’ve noticed is that the soft filament is challenging for the extruder to push down into the nozzle and force out the tip – it is quite common for the nozzle to clog and filament to keep feeding through until it comes out the back of the extruder. Luckily nothing has jammed up yet, you can pull the filament back up out of the extruder and try again. With a bit of a search online, it seems that some 3D printable parts may solve this problem, in particular this modified Extruder Drive Block available on Thingiverse which closes the opening where the filament likes to escape, and will hopefully better force it down through the nozzle. The video below from Wanhao USA helps highlight the problem, and how this 3D printed part can fix it.

It’s early days with this filament, and I know the stock extruder of the Duplicator i3 is really not optimised for this type of material. But it can be done, and I’m sure with some tweaking can be made more reliable. Stay tuned as I am currently printing the new block to install on the Duplicator in the coming days, and will report back with results.

– Posted by James Novak

Motorbike Indicator Adapters

20160227_Bike Indicators

An issue with owning an older (well 2007 isn’t really that old!) motorcycle is that finding parts gets harder and harder. The previous 3D prints for my bike (such as rear peg plugs, key guard and mirror plugs) have really just been cosmetic, but after buying some sleek little LED indicators to replace the huge stock ones, I came across a problem – the fitting point for the rear indicators is specific to the shape of the stock ones, which is a really large cut-out and has nowhere to install the standard indicators designed to fit most bikes. There was also nothing online I could find ready to buy. One option would be to simply drill a new hole through the plastic mud guard, but this would leave the previous holes on show and mean that if for some reason someone ever wanted to put the stock indicators back on, they would now have these new holes to deal with.

No, not on my watch! My first idea started with trying to fit something from the inside of the mud guard, plugging the hole and providing a new point to mount the LED indicators inside of this. The problem was measuring this area, with other wires and complex shapes, it became quite challenging to get any accurate measurements. Since I’ve already used the green PET+ filament on the bike, I may as well make this indicator adapter a feature, and use the flat outside face of the mud guard to easily create a paper template as shown in the top left image. This was scanned, traced in Adobe Illustrator, exported as a .dxf file, and then imported into Solidworks to create the final 3D form. This might seem like a lot of processes, but is a really accurate method of getting a starting point for 3D modeling when dealing with flat surfaces using basic equipment at home.

The final 3D print pictured was done on my new Cocoon Create using 0.2mm layer thickness and took about 55 minutes to print. While the final design looks flat, there are a few tricky details on the back used to lock it in place with only 1 screw (thankfully the mud guard had a useful threaded hole for mounting). I will now be interested to see how well the PET+ plastic holds up out on the road – it seems quite secure, and the indicators are very lightweight, but who knows what can happen out on the road.

– Posted by James Novak

UPDATE: I am now trialing the use of Sketchfab so you can easily view 3D models of my work – check it out below!

Cocoon Create Extruder Fix

20160218_Cocoon Create Extruder

After yesterday’s exciting successes with my new Cocoon Create 3D printer from Aldi, today there have been some hiccups – namely I tried to change filaments and could not load any new filament into the extruder. The filament would start to load, and after about 5mm there would be a “clunk, clunk, clunk” sound as the motor was grinding the filament but not pushing it any further down. Being jammed, there were 2 possibilities; either the filament was not able to find its way down towards the nozzle because something was misaligned, or there was some old filament jammed in there. So after only 24 hours of ownership, it was time to hack at it and take apart the extruder. It’s actually very easy, and I’ve used the photos above to try and illustrate how to fix a jam.

  1. Use an allen key to remove the 2 screws on the left side of the extruder – be careful as these hold the entire extruder together, so you want to catch the parts rather than let them drop. Also make sure your nozzle is nice and cool!
  2. The fan can just hang from its wires, but the heat-sink and 2 white spacers can be removed, leaving the motor and feeder as shown in the second photo. This is what feeds the filament down into the nozzle (entering from where my thumb is). Check for any loose material in here and clean (mine was fine).
  3. As circled in photo 3, this little piece of the remaining first filament is the culprit of my jamming. It wasn’t enough to grab with pliers, so I just turned on the printer, heated the nozzle, and then used a small allen key to push all the material down through the extruder, leaving a large opening for the new material to enter.
  4. Done. Just re-assemble and make sure all the little wire connections are firmly attached.

This quick process solved the problem and new material loaded without any further problems. After looking on the Cocoon Create website it seems that there is almost no support or FAQ as yet, so I hope this helps anyone stuck.

– Posted by James Novak

Solidoodle 2nd Look…is it meant to do that?

So my second play with the new Solidoodle Press has been challenging, and still no prints to show for it. While yesterday’s post of my first impressions was quite positive, now as I’m trying to calibrate and print there are plenty of questions being raised (which it seems like most owners are having as I’m searching online for fixes/answers). A great place to find out about all the bugs and issues people are experiencing is the SoliForum – especially if you’re searching for fixes, or considering buying a Press.

The first thing I’ve come across is that the automatic z-axis calibration doesn’t work at all. No major problem, since the printer automatically levels each time you go to print anyway (as in the video above). But definitely wasted some time trying, switching everything off, disconnecting plugs, re-trying, waiting… you get the gist! Hopefully the next SoliPrint update will fix this, from the SoliForum it looks like the previous version of the software worked fine.

Now actually running a print has been the ultimate challenge, and one I’m yet to conquer. The above video shows what happens when you go to print after following the instructions from Solidoodle (Getting Started Guide), with the filament not sticking to the glass plate. Having looked around online, most people have very quickly gone to hairspray, water-soluble glues, tape, mixtures of acetone and ABS… the list goes on and sounds like the sort of random advice a witch doctor would give. However if a secondary product was required in order to print, don’t you think Solidoodle would supply this in the box? This is the very reason I’ve avoided the original Cube printers we have at my university, and relied instead on the Up! Plus 2 which uses a perforated PCB board as the printing plate and therefore requires no gluing. With all this technology, surely we can do a bit better than having to make a mess and spray glue everywhere? I’ve bought some perforated PCB’s from Jaycar (pictured below) so will see if I can use these as a plate before getting my hands dirty with glue. I couldn’t find a single one large enough, so these 2 might be OK.

2015-02-07 Solidoodle 2nd TimeThe scariest problem I came across was during the second attempt at printing, when there was a loud grinding/buzzing sound from within the machine! I couldn’t get my hands to the power fast enough to shut it down! The second image above shows what caused the problem, with the black cable cover getting wedged behind the arm of the extruder, stopping it from going to it’s starting position. I have since seen a post from Solidoodle acknowledging this problem, and have found that by twisting the cable cover around I can prop it out of the way. But I will definitely be looking at a more secure solution to this problem; seems like if so many people are experiencing the same thing there just wasn’t enough testing by Solidoodle prior to shipping. Hopefully no real damage has been done to the machine. Again check out the SoliForum for a range of fixes, including a 3D printable clip on Thingiverse (although if you’re having problems printing in the first place, this might not be for you!).

Another concern I had yesterday (read the post by clicking here) was that the very nice, professional housing for spools of filament wouldn’t fit third-party spools. And I was right (third picture above). I’m sure by keeping the upper lid open there will be no affect on the printer, it just looks a bit less ‘contained’ and thought through as a product. Surely with the variety of options available worldwide 3D printer manufacturers need to just accept that we all want to experiment with materials and may not want to wait weeks and weeks for their ‘propriety’ filament to ship when a local supplier can provide it in days (without the high shipping costs as well).

Screengrab - non-centeredFinally the SoliPrint software of course has a few noticeable bugs besides not calibrating the z-axis. The main one I’ve come across already is that while you can move your imported model anywhere within the print volume, the printer will still print in the center of the plate. By a bit of experimentation I found that in the menu Options>Slic3r Options, there is a ‘Print Center’ setting which by default is 100,100. By changing these values, you can determine where on the plate is considered the center of your model (providing you know which X and Y coordinates are which). Hopefully this is also rectified soon, the print should just match the on-screen preview.

Well that’s day 2 of my experimentation, really hope that next time I will have some success actually completing a 3D print. I think it’s clear that the Press is far from a consumer-friendly, plug-and-play machine at this stage. I’m sure with time it could be, but not yet. A non-3D print nerd would already be demanding their money back and wondering what all the fuss about 3D printing is. Stay tuned and please comment and share if you’ve gone through a similar process 🙂

– Posted by James Novak

Beer Bottle Lock – Remixed

2014-12-17 Beer LockFirstly let me state this is not an original idea – recently a Beer Bottle Lock made the rounds on 3D printing news sites, stemming from an Instructables tutorial by JON-A-TRON (click here to see the original DIY Instructable).

However I thought it was a lot of fun with Xmas coming up, so decided to make one for a member of my family (hence the writing on top “John’s Beer”). Great little project involving measuring (and inevitably drinking!) lots of beer, and designing around this base model. The main difference between my design and that of JON-A-TRON is that mine requires no screw – it holds together once once locked around the bottle top, even though it is printed as 2 separate parts. I think my design is also ‘slimmed- down,’ therefore probably easier to snap off if someone really wanted to – however this really is just a bit of fun, anyone who seriously wants to lock away their beer either has some paranoia issues, or just some dodgy mates!

I still want to make some changes, but once complete I may upload to Thingiverse for you to enjoy 🙂 This is also my first print with a new (to me) brand of ABS called Zortrax, running it through the ‘Up! Plus 2‘ 3D printer. So far really happy with it, and EXCELLENT price from ($32.95 per Kg). Check it out here if you’re looking for cheap filament in Australia.

– Posted by James Novak