Recline

Here's my new project.  I've started a collection of potential sculptures on Pinterest and, having printed several curled up models, I fancied trying a more open, reclining pose like this one.  I have now discovered that this is one of the 'Square Nudes' series by Carsten Witte.

The amount of support material required should be fairly minimal although the steep angle under the upper back may need some.  Additionally, the palms of the hands are raised off the ground and will also need supporting. 
Another of the challenges will be to deal with the area where the thighs and calves will inevitably overlap after posing the model.

More to follow ...

Turns out that I still haven't quite got this 3D printing lark completely sussed yet. The modelling went quite well. I even broke with tradition and tried leaving the mouth open a bit to allow the front teeth to show. This, in turn, meant having to devise a different technique for closing off the open edges in the mouth area.

As usual, I opted to use Kisslicer to generate the gcode because I still find that it produces the best support material. The problems started when I began to print. In spite of the fact that I was using the same settings as I have for all my other prints (ABS at 240C, 0.2 mm layer height, 0.4 mm line width), the extrusion seemed thinner than usual and the inter-layer bonding was poor. The model finally appeared from the build chamber with several large cracks including a complete break in one of the arms.

The other major problem was that the fingers appeared to be poorly formed and looking as though they might come away with the support material. I haven't tried removing the support yet, due to lack of time, but I really don't hold out much hope for saving this print. 

One of the factors that has changed is my new hot end which has a 0.4 mm nozzle, whereas my previous one had a 0.5 mm diameter hole. Slic3r includes a place to enter the diameter of your nozzle but apparently Kisslicer does not.  I have never quite understood the logic of this, so I don't really know whether it could be a possible factor in explaining the latest failure.

I'll probably give it another try and maybe just turn up the flow rate a bit.

Bridge printed

My test print of Bridge was successful at first sight, but on closer inspection the leotard had been only partially printed, particularly across the back where it was rather messy. In other places, it was a completely separate and rather fragile layer which started to come away as I removed the support material. So, in summary, my first faltering steps with printing clothing had been a bit of a failure. I decided to try and recover an otherwise good print by breaking away the remnants of the leotard.
A bit of scraping with a knife and an acetone vapour bath later, and I had another nice looking model.

Before removal of support material and leotard fragments

Curl

I decided to have a go at reproducing the pose in Jian Xu's picture shown at the bottom of my last post. Tricky parts included getting the fingers into the correct position, particularly since it seemed to push the right elbow into odd places, and dealing with the deep mesh overlap where calves met thighs and thighs met trunk.

I'm still struggling to get good quality solid hair and I don't always like the models looking bald! This time I used Sculptris to fashion a short hair style starting from a simple sphere. It's not great but it kind of works.

Here is the cleaned up version in Blender beside the reference picture.

Metamorphosis looked beautiful in the translucent blue but, being made of PLA, I couldn't use the acetone vapor bath to smooth the surface. PLA isn't soluble in acetone. I knew that I wanted to have a smooth surface on Curl, so I thought I would try printing a copy in black ABS.

My first attempt was sliced in Slic3r 0.98 but again I was disappointed with the way it generates support structures, so I abandoned that print and sliced again in Kisslicer. This version looked much more promising and I have learned that the initial raft is an indispensable feature for supporting this type of model.

Here is the model on the print bed and in close up, showing the support structures (under LED lighting).

Here is the bottom section of the support material after it was peeled away from the model. I am still impressed with how well the support separates from the model given that they are both made of the same material.

And here is the final version after processing in acetone vapor.

Finishing

The surface appearance of a Fused Filament Fabrication 3D print is determined by a number of factors.

• Size of the print - larger prints will show more detail with a high resolution STL file
• Height of each printed layer - at 0.1 mm and below the layers become much less visible
• Extrusion temperature - some plastics become duller when printed hotter

After the print is completed there are some 'post-processing' techniques that can be used alter the finish.

Cosmo Wenman is making great progress with his artificially aged bronze statues and is planning to release a range of finish materials.

PLA can be smoothed with a hot air gun although there is a danger of warping the model if the temperature is allowed to get too high.

Dipping the model in an acetone bath can work well for ABS.

The newest technique was recently described by Spacexula in this YouTube video and involves placing the model in a heated chamber with a small quantity of acetone which then vaporises and coats the surfaces. The effect looked dramatic so I decided to give it a try.

Here are the results of my first two attempts.

The surface is now smooth and shiny even though it is completely dry and hard to the touch.

Pensive

The 'Sun worship' model took me at least five attempts to get a decent print from, but having finally got it to the point where I was happy with the output quality I decided it was time to move on and try a different design.

There are many factors to consider when designing a model for printing on a 'fused filament' type of 3D printer, like a RepRap or Makerbot. One of the most important ones is the the need for 'support material'.

The printer starts printing the bottom layer onto a flat bed (usually heated to 100°C to make the plastic stick to it) and then proceeds to print each successive layer on top of the one underneath. This works fine for blocks with straight sides and can even cope with sloping sides of up to 45 degrees where each layer projects out a bit further than the one below.

But in real life, things stick out at all sorts of angles and this presents a problem. Just take a look at the middle of your face and imagine how difficult it is to print chins and noses. The printer is squirting hot, runny plastic filament downwards from the nozzle and needs something to extrude the plastic onto. If there is nothing there, the string of plastic will just hang down in mid air instead of following the path that the nozzle is tracing as it draws.

Sun Worship

One way to address this problem is to create support structures which are not part of the sculpture, but are solely intended to provided a surface for the upper layers to land on. 
Another way is ensure that the model has no projecting angles shallower than about 45 degrees.
Look again at the Sun worship model and you will see that all of the limbs, the torso and the head have been carefully posed to ensure that there are no unsupported regions.



I decided that my next project would be a nude sculpture of a woman standing in a pensive pose, one knee slightly bent and arms held close to the chest. 


After working through a number of iterations I arrived at this pose.


Again I spent a considerable amount of time fixing the mouth and eyes and creating a customised hair object.

It turned out that there were several problems with this model. Firstly, the points of the elbows and the chin had nothing beneath them so I decided to add some small support blocks for removal after printing.


In this picture, you can just make out the small disc between the thumbs, as well as the triangular elbow supports.


This should have worked in theory, but in practice the chin support was too thin and failed to print correctly, while the elbow supports ended up too close to the model and caused an unsightly mess.






The other big problem was that my printer can only go up to a height of 13 cm and even using the full print height the model still ended up quite small.
This would have been OK had it not resulted in the fingers becoming too thin to print correctly.
Here is one of the early attempts demonstrating some of these problems.

I made a number of significant changes to try and improve the quality of the print.

• Moved the elbows closer to the abdomen and removed the support blocks
• Repositioned the thumbs under the chin
• Slightly fattened the fingers and thumbs
• Increased the height of the model to 20 cm
• Printed in two halves, with a connecting pin to join them back together

The fingers are little bulky and the seam is still visible but this is straight off the printer, with no post-processing work.

Pensive

Incidentally, you can see the legs of this model being printed in the very first picture of this blog.

Welcome to 3D Printed Nudes

Home 3D printer ownership and use has exploded over the last couple of years. These small but powerful machines are capable of creating solid objects by melting plastic filament and depositing it precisely in thin layers, building strong, solid shapes that can be both functional and aesthetically pleasing.
Printers can be built at home from a kit for about $750, or purchased ready to use for about $2000.
Almost all of the software needed to create and print digital 3D models is available as open-source freely downloadable files.

The 3D printer in action

Why print nude sculptures?

• Classical sculpture has used the nude human form as subject matter for thousands of years. Humans innately find beauty in representations of the human form.
• The smooth, subtle, sensuous curves of a naked body present a real challenge for machines that are typically used for making mechanical objects based on digital models.
• Many great statues can be captured for printing using an ordinary digital camera and a free online service such as Autodesk 123D Catch.
• 3D modelling software already offers the capability to create digital compositions that can be exported in a printable format, but these files are not generally printable without extra work.
• Adding clothing on top of the models, significantly complicates this process. Making printable nude sculptures is both pleasing and much simpler.

There are many challenges to be overcome and I aim to make this site a place for sharing ideas to improve printing quality as well as a way of sharing some successes and failures.

Here is a new sculpture called "Sun worship" that was processed in Blender to make it ready for printing.

Sun Worship - face detail

Sun Worship - hand detail

Sun Worship - feet detail

Sun Worship - with ear-buds for scale