Mannequin Head Remix

3D Print Mannequin Head

Close but no cigar.

Sometimes you find something close to what you want on Thingiverse, Pinshape or other 3D printing platforms, but it’s just not quite right. Well, there is often something you can do about it, and it won’t cost a cent.

I’ve written several tutorials about using free software Meshmixer to make various modifications, for example creating a mashup of 2 different files or adding some text to a design. On this occasion I found a 3D scan of a styrofoam mannequin head on Thingiverse, which included all of the messy details you’d expect from a foam model (smaller head in the image above right). Great if you’re after realism, but not great when you want nice smooth surfaces for 3D printing. The model was also not at the correct scale, and I wanted a mannequin head to use as a model.

The scale was an easy fix, and of course could be done in your slicing software.  Cleaning up the surfaces was also quite simple using the ‘Sculpt’ tool and choosing one of the smoothing brushes. This essentially irons out all the rough details, smoothing out the model as you brush over it. A few minutes of work and a rough model is now clean and ready for 3D printing – which of course I’ve uploaded as a remix on Thingiverse so you can download it for yourself.

The above left image shows the 3D printed result from a Creality CR-10 S5, a very cheap, very large FDM machine with a build volume measuring 500x500x500mm. Obviously my settings weren’t great, the seam is in the worst possible position, and because I wanted a quick result I used only a single wall thickness and almost no infill, which split apart at the top. However, it’s fine for my purposes, and the surface quality on most of the model is fantastic.

Happy smoothing!

– Posted by James Novak

Fingerprint Stool 3D Printed on a BigRep ONE

Fingerprint Stool BigRep ONE

Size matters!

I’ve been throwing out teasers about this project on social media for over a year, and with my research just published in the Rapid Prototyping Journal, it is very exciting to finally be at the finish line and able to share it – all of it! So what exactly is it?

Well, it’s a 3D printed stool. But more than that, it’s the outcome of a design for additive manufacturing case study using the new BigRep ONE 3D printers, housed in the ProtoSpace facility at the University of Technology Sydney. The BigRep ONE is essentially a desktop FDM 3D printer on steroids, with a build volume measuring 1005 x 1005 x 1005mm, that’s over 1 cubic meter of space to 3D print! And much like a desktop FDM printer it uses filaments like PLA, PETG, TPU and realistically just about any other filament material, as well as using a Simplify3D profile for slicing, so designing for the printer and operating it is identical to many common desktop 3D printers.

edfGiven the newness of these machines when they were installed in ProtoSpace in early 2018, my job was to test the capabilities of them whilst developing a showcase product to highlight how they can be used to develop new types of products, and with such a large build volume, furniture was an obvious choice. However, my budget was not unlimited ($1500 AUD) and nor was the time I was allowed to run the printer, which was capped at 5 days so that it was not taken out of commission for other users for more than one working week. Sounds like a generous timeframe unless you’re familiar with just how slow FDM printing is even at the desktop scale, and while this printer is bigger, it is certainly not any faster. And when you are printing for 5 days, this machine will really chew through filament, so that $1500 budget quickly runs out.

In terms of the fingerprint concept, the stool was designed when I was newly engaged and uses a fingerprint from my (now wife’s) ring finger, and my own. Awwwwe… There are few features more unique to each human than a fingerprint, so this concept was also chosen as a truly unique feature that highlights the capacity for 3D printing to be used for one-off personalised products.

The above video helps explain the design and printing process, which essentially involved:

  1. Ink used to take impressions of fingerprints on paper.
  2. Fingerprints digitised using a flatbed scanner.
  3. Fingerprints vectorised in Adobe Illustrator. Exported as DXF files.
  4. DXF files imported into Solidworks CAD software and oriented 420mm apart for the height of the stool.
  5. Manual creation of the 3D geometry.
  6. Export to STL.
  7. Slice in Simplify3D.
  8. 3D print on the BigRep ONE [1mm nozzle diameter, 0.5mm layer height, 5% infill, 2 walls, 3000mm/min print speed]

Sounds nice and straight forward. However, I must admit things did not go this smoothly: Firstly, designing to fit a specific budget and print time required several iterations, with an early version of the design twice as large as the design pictured here. This meant initial cost estimates were in the range of $2194-3882 and print times 117.5-216.1hours – talk about variation! All of this variation is due to experimenting with process parameters like layer height and nozzle diameter for the same design, and was an important learning process that could be taken back into later iterations of the design, which ultimately became smaller.

Fingerprint Stool BigRep Adhesion

Secondly, another obstacle we struggled with was bed adhesion. This is a common problem with desktop machines, however, not normally when printing with PLA. We quickly found that during the first layers, a slight warp or piece of material sticking up would get knocked by the extruder, causing a knock-on effect as the extruder and any material it had collected quickly cause all of the individual sections of the fingerprint to dislodge. Pictured above on the left is the largest section that printed before some material snapped off and somehow caused the nozzle to become entombed in PLA, pictured above on the right. That was an expensive error, new nozzles for the BigRep ONE do not come cheap!

Given the design was intended to print without any need for support material, we eventually had to concede defeat and add a raft. This had the effect of linking all of the initially individual sections of fingerprint together during the first layers, and provided a strong adhesion to the bed. While we could’ve tried all sorts of glues, tapes and other hacks, we didn’t want to resort to these on such a new machine until we had more time to test settings and work with BigRep on a solution. The good news: the raft worked and after 113 hours, and at a cost of $1634 (only slightly over budget), the Fingerprint Stool was complete. The raft did take 1 hour to remove with a hammer and chisel (with a 1mm nozzle there is so much material it cannot be removed by hand), and the surface finish is quite rough – but in my mind this is the charm of FDM, just like a piece of timber has grain and knots that are simply part of the material.

Overall the BigRep ONE is an exciting technology, you just need to keep in mind that due to the scale, all of the small issues you can experience on a cheap desktop machine are also magnified. However, it is great for producing large-scale functional parts like furniture, or any of the other examples you may have seen from BigRep in 3D printing news over recent months.

This is a brief overview of the project, there is much more technical information and analysis in my paper in the Rapid Prototyping Journal, including metrology data of the final design compared with the 3D file, as well as surface roughness data. I’d love to hear your feedback on the project or your own experiences with the printer if you’ve been lucky enough to use one. And keep an eye out for updates about the stool appearing in an exhibition later in the year 😉

UPDATE: Thank you to BigRep for taking an interest in this project and writing their own story about it here, and to 3D Printing Industry for also sharing this story.

– Posted by James Novak

3D printing is cool, but have you tried 2.5D printing?

20190617 2-5D Print Thin Wall 3D

Over the last 18 months or so I’ve been stripping back FDM 3D printing to its basics, experimenting with a variety of materials, composites and patterns designed to be printed flat and assembled into more complex 3D forms. Why?

Well there are many reasons why you might want to use a 3D printer to create relatively flat forms: firstly, as anyone who has used a 3D printer would know, the process is extremely slow. The less vertical height you need to print the faster your part will be completed (generally). Secondly, most accessible 3D printers have a very small build volume, and often you want to 3D print something huge. By 3D printing a lot of smaller, flat parts and assembling them later, you can create a large 3D printed object on a small machine (for example check out the full length inBloom Dress by XYZ Workshop which was assembled out of 191 smaller panels).

This type of 3D printing has actually been called 2.5D printing, since it is essentially the production of 2D geometry that is extruded in a single direction. No fancy lattice structures or compound curves here! Below are some examples I’ve printed over the years, and while some of them like the mesostructure (centre) may look complex, the geometry can be described by a single 2D drawing and extrusion (Z) dimension.

20190617 2-5D Print Examples

What I’ve learned is that when you are 2.5D printing often thin geometries, optimising the dimensions of the geometry for the specific capabilities of your FDM machine are critical. In fact, just a 0.1mm change in the thickness of a wall can reduce your print time by ~50%, which is a huge time saving. Knowing what these “magic” wall thickness settings are is powerful, and also very simple when you understand the logic.

This information has now been published in a book chapter titled “Designing Thin 2.5D Parts Optimized for Fused Deposition Modeling,” and provides several equations you can use to quickly calculate the optimum dimensions you should use if you want to 2.5D print (or even 3D print) as quickly as possible with maximum accuracy. Below is a visual graph that can be used to select the optimum wall thickness settings when 3D printing with a 0.4mm nozzle, and also shows the effect STL resolution can have. Full details about this graph can be found in the book, however the short version is that you want to be designing thin wall features using dimensions that fall inside the black boxed (or dashed) regions. So, for example if you will be using a 0.8mm printed wall thickness (representing 2×0.4mm extrusions in your slicer), the optimum dimensions to design with in CAD are 0.5-0.8mm, 1.3-1.6mm, or 2.0-2.3mm. Anything outside of these dimensions will require some level of infill structure which takes longer to print, and can result in a more messy part.

20190617 3D Print Thin Wall

For a part similar to the mesostructure earlier, we calculated that simply adding 0.1mm of thickness to the design from 1.2mmm up to 1.3mm would decrease print time by 38% – yes, it sounds counter-intuitive, but adding material can actually reduce print time!

Designing for additive manufacturing (DfAM) is a very important research area, and it is knowledge like this that I hope can be implemented by designers, manufacturers and others involved in 3D printing. If you want to learn more about 2.5D printing, and the equations you can use to calculate the “optimized zones” for your own 3D printer, please check out my chapter which can be purchased with a 40% discount using my author code “IGI40,” or if you are at a university you may find you already have access through your library subscriptions.

Happy 2.5D printing.

– Posted by James Novak

#3DBenchy, the Most Downloaded 3D Print

20180914_3DBenchy

If you are involved in 3D printing there’s no doubt you’ve at least heard of #3DBenchy, if not printed one, or two, or even more. What is #3DBenchy? Well, it’s a tug boat of course! But more than that, #3DBenchy has become like the “Hello World!” from coding, the go to 3D model to test out a new printer or setting. Why a tug boat? That’s a very good question, and the only real explanation is that it includes a number of features that challenge a printer including overhangs (e.g. roof) and a variety of angled surfaces. Also, it’s a little more interesting than a basic calibration cube or set of test prints.

#3DBenchy was developed by a company called Creative Tools, initially as an in-house calibration test for their own printers. On April 9th 2015, Creative Tools uploaded the design to Thingiverse for anyone to download for free, and the rest, as they say, is history. Since then the file has been downloaded over 600,000 times from Thingiverse alone, and can be found on pretty much any other 3D file sharing website. #3DBenchy even has its own website, Instagram profile, and Twitter account – talk about a famous 3D print!

I’ve never seen any need to jump on board the #3DBenchy bandwagon, however, I was recently writing up some research that required me to photograph a #3DBenchy, and I’m always up for an excuse to print something new. So here we are, #3DBenchy in hand, and given I used some relatively fast settings to get it printed in about 1 hour, I think the result is quite good. This one is the original #3DBenchy at full scale, printed without support. And of course my photos have been fed back onto Thingiverse as one of the 2788 makes of #3DBenchy, and one of 2961 posts on Instagram… and counting. Vive la révolution!

– 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

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

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

Giant 3D Printed SUP Fin

20170511_3D SUP Fin

Behind the scenes I’ve been working on a Stand Up Paddle (SUP) fin project for quite a while now, 3D printing many prototypes, and more often than not, failing! There is more to this project than meets the eye, but for now the details are under wraps. However I thought it might be interesting to share some of the 3D prints in case anyone feels inspired to give it a go themselves.

The design pictured above is the first one that worked successfully without breaking or having other technical issues. Printed in 4 pieces on my Cocoon Create due to the size, it required a bit of gluing, and as you can see from the pink highlight, a bit of gap filling with a 3Doodler Pen (if you want to know more about using a 3D printing pen as a gap filler, check out one of my previous posts all about it). As a result the fin is about 400mm long, huge compared to the fin that came with the board (which for any SUP fans out there is a Slingshot G-Whiz 9’4″)

20170511_3D SUP Fin

These images show some of the breakages I’ve had due to layer delamination – unfortunately the optimal way to print the 4 pieces in terms of minimising support material and warping is vertical, however the optimal orientation for strength is laying down on the flat sides (similar to the image on the right). A bit of an oversight on my part I’ll admit, however I was genuinely surprised how much force the flat water put on the fin. Another issue may be the minimal infill, which was also beefed up in my later prints to add internal strength. There is always a delicate balance between print orientation, layer strength and infill in 3D printing, to name just a few!

The main thing is that the fin prototype now works, and I may have a more advanced version being printed using Selective Laser Sintering (SLS) as I write this… If you keep an eye on my blog by subscribing below, you may just get to see where this project is going 🙂

– 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.

collage

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