<![CDATA[Elemental Miniatures - Blog]]>Wed, 24 Feb 2016 22:43:40 -0800Weebly<![CDATA[De-Mystifying 3d: PArt 4]]>Sun, 01 Sep 2013 20:43:17 GMThttp://www.elementalminiatures.co.uk/blog/de-mystifying-3d-part-4In this post, I am showing a quick walkthrough the process of making a model. There won't be much reading- just a few notes after images. I will be making a sword ready for use with a character...
This is the concept image (with apologies to actual concept artists) for a slightly battle worn, bulky weapon such as might be used by an Orc or other evil creature...
Firstly, I build a base mesh outside of Zbrush- for this I will use Blender...
I build a fairly basic base mesh- no detailes, just enough to capture the overall shape of the sword. This is enough to get cracking in ZBrush...Zbrush modelling has a lot of stages, but luckily it allows me to capture a timelapse video, so here is the next few stages...
After processing in Zbrush, the final sword is ready to send to print or use on a character project. Here it is! Hopnefully, brief as this is, some light has been shed on the basic process of creating a model in 3D for miniatures, as opposed to using

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<![CDATA[De-mystifying 3d: part 3]]>Sun, 25 Aug 2013 14:46:16 GMThttp://www.elementalminiatures.co.uk/blog/de-mystifying-3d-part-3Picture
In the previous entry, I talked about the process of getting useable data that a 3D printer can work with to create a physical model. 

In this entry, I will look at some of the software and considerations involved in creating a model ready to send to the stl stage.

The two principle pieces of software I use for model creation are Zbrush by Pixologic and Blender by the Blender Foundation. 

Zbrush is my main tool of choice; it is the premier sculpting tool for 3D and has a number of features that make it particularly useful for creating meshes that will make good stl files. It even has its own 3D stl exporter, which works very well.

Blender is the tool I use for base mesh creation and modelling hard surface objects such as guns, swords and armour pieces. Blender is a powerful tool which has the advantage of being completely free, so I encourage anyone interested in 3D modelling to have a go with Blender!

So, with these two tools, how does a model get planned? 

Here are two images, one of the gun from my previous entry and the Acthung Cthulhu Servitor Officer from Modiphius Entertainment.

The gun features a number of tiny elements- thin barrel, small trigger, numerous tiny embellishments, which are unsuitable for making a miniature. The nature of a resin, plastic or metal part is limited by both the strength of the material and the ability to force the material into the mould when casting. These tiny parts serve to make the gun unusable in its current state.

Compare it with the SMG the Officer carries- a much thicker barrel, and much less detail, this nonetheless ends up being a fine and detailed piece when it is finally made. A judgement on scale must be made at all stages, and the model on the screen can be deceptive.

Also, with the Officer model, the miniature must be split into several pieces for casting. All moulds are a two part assembly. This means that any miniature must be planned with this in mind. There can be no places where the mould would trap itself, no severe undercuts that could lock the miniature into the mould and nothing that sits too far off the axis of the mould line.  In the image below, these issues can be seen:
The solution here, and with most models, is to separate these parts and make them into a sprue of additional pieces. This has the effect of increasing the production cost of the model, so there is always a trade off between dynamic poses and how much the mini will cost to buy!

It is worth noting here that there are not many guides to this process; most of the 3D modelling tutorials that you can find online have a VFX and videogame focus. Consequently, there is much written about animation, texturing, normal mapping and edgeloop topology which doesn't have any relevance to making minis. Digital Tutors, Gnomon and others offer many excellent tutorials and artist masters such as Ryan Kingslein have astonishing material available, but you need to be ready to pick, choose and adapt it to suit miniatures sculpting. In fact, some tutorials come with a potential health hazard:

Solutions for generating cool textures and maps for gaming can produce unusable files for printing! 


Generally, sculptural tutorials and tutorials on core functions of programmes such as ZBrush are excellent. Tutorials about making the 'high res' models from game pipelines can also be helpful. However, much of the information about baking maps and fooling the eye in games, or setting up models for animation in VFX, can lead to adopting processes that make a mesh impossible to print- one example would be creating game efficient models by using double sided polygons to create blades or deleting unseen faces from the backs of pouches. Two common practices found in tutorials that creates the dreaded non manifold (real world impossible) mesh! 

For a different take on things, the miniature sculpting tutorials at Miniature Mentor, whilst having nothing to do with digital sculpting, can offer some great insights into the miniature process for traditional mediums, which can be translated into the digital world. 
Also, most computer and VFX targeted 3D models are proportionally different to the average miniature. Whilst sites such as Turbosquid offer great models for a price, an artist planning to make miniatures must be ready to make significant alterations to any model that is purchased. 

That's all for this post. Next time, I shall detail making a simple weapon from scratch to show the full 3D process from concept art to finished file. 


Thanks for reading!
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<![CDATA[De-mystifying 3d: Part 2]]>Sun, 18 Aug 2013 08:55:26 GMThttp://www.elementalminiatures.co.uk/blog/de-mystifying-3d-part-2Picture
Before I begin: Congratulations to my friends at Clockwork Publishing, Modiphius Entertainment and Chronicle City...

The Space 1889 Kickstarter is roaring to its conclusion with funding achieved for all sorts of great stuff, including miniatures!

Achtung Cthulhu is an ENNIE award winner for its 'Three Kings' adventure supplement, and the team are having a great time at Gen Con!

Last time, I talked through some of the materials and processes involved in printing a virtual model into a physical reality. However, regardless of what print method you use, the printer will need the model in a data format it can use. This blog entry is going to briefly summarise how this works and why it's not as easy as you'd hope!

The most commonly accepted file format for 3D printing is the STL (standard tessellation language) file. This format converts a 3D editable mesh (OBJ, MAX, DWG, etc) into a non-editable set of geometry data that a printer can use to create its print layers. The printer software will take any model and 'slice' it into individual pieces that each represent one print layer. If you're familiar with card 'sculpture puzzles' then you will appreciate the process. 

In this example of everyone's favourite movie character of all time, layers of cardboard stack up to create the illusion of a 3D object.  The 3D process for printing is exactly the same, only the layers are many times thinner and finer. 

It is because of this approach that 'support' material is needed- if part of a model connects to the whole at a point that prints later than the rest of that part, without a support, it would be disconnected and float away from the print.

However, before that stage is reached, there are a number of issues that have to be checked to create a printable STL. 

The big three are:

  • Is the mesh one shell?
  • Is the mesh manifold?
  • Is the detail geometrically real?

Here is a gun OBJ from a 3D model online store. Perfect for a video game model, it will not work for printing. Although it looks like a single object, it contains many 'shells' or parts.

The next image shows some of the many separate shells that form the gun- over 100 in total and some are tiny. The 3D printer will attempt to treat each as a separate object. Some simple printers can handle this, but anything detailed enough to produce models useable in casting will not cope- leading to a long and expensive process of manually fixing by the printer operator.  

The third image shows a non manifold cube- some of the faces that form the cube are either missing or inverted (facing inwards).  3D faces have no thickness and only have one side- there is no depth data and the inner sides are not calculated, so only a fully closed shape is physically realistic. This means the object cannot exist 'in the real world' so will not print.

The final image, from Gears of War 3 by Epic Games, shows how the detail on this model, like many game models, is created through beautifully crafted textures.  This allows the game engine to create detailed models at high framerates. However, none of that texture or detail will print- the flattened wireframe model is the actual figure that will be recreated. 
Although many 3D programmes can export in STL format, they cannot fix these issues themselves.

Some of these issues can be fixed when making the model, which I will talk about next week. Some of them can be fixed after completing the model using 'mesh checking' software such as meshlab, magics or netfabb. These programmes use algorithms to check for inverted or missing faces and holes, and weld together loose shells. They then write the file as the STL the printer needs, from whatever 3D format was imported. They cannot alter the model too much and some of their fixes can be destructive to details, so it is better to prepare the model for printing as it is created. They cannot do anything about detail from textures- this is a sculpting concern!

Prepping a model for print is about more than just the technical hurdles- there are other concerns to do with casting limitations, material limitations of pewter, resin and plastic, and getting a crisp and paintable miniature too! 

Next entry, I will look at how I created one of the Acthung Cthulhu miniatures, what decisions I made and how this helps the process. I'll also return to these example images- they have more to reveal!  I will also talk about why much of the VFX training and Video Game modelling techniques that are found online can actually hinder the process of creating miniatures!

Thanks for reading!
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<![CDATA[DeMystifying 3d- part 1]]>Sun, 11 Aug 2013 18:11:16 GMThttp://www.elementalminiatures.co.uk/blog/demystifying-3d-part-1Picture
3D printing is a relatively new process for producing miniatures. In this blog, I will attempt to make clear the way that 3D printing can contribute to making miniatures, the benefits and pitfalls, and what I see as the future of 3D for our hobby.

In this post, I am going to explain what 3D is, how it works and what the limitations are.



It might look like magic, but at its heart, 3D printing is derived directly from the desktop printers found in most homes and offices in the world. When your desktop printer prints a page of text, every letter is placed by a moving print head. If you were to take a micrometer, you would find that the ink left on the page had a physical height- albeit it a very small physical height! If you were able to repeatedly run the same sheet of paper through the printer, and the printer was accurate enough to always print in the same place, eventually the layers of ink would be thick enough to feel with your fingers.

This is how 3D printing works. A 3D printer places layers and layers of material in a set pattern to create a physical object. What makes a 3D printer special is the ability to move its print head or the print bay up and down, the accuracy of the print mechanism for placing the print, and the material that you can print in. 

There are many materials and processes used in 3D printing, with new applications being found all the time. Let's look a a couple that are useable for making models...

- Acrylic resin: Probably among the most common type of 3D printing material, most materials have a resin based or plastic component. Companies such as shapeways and i.materialise advertise various types of resin based materials. The finest quality resin printing available from such services is usually called something like 'frosted ultra detail' (FUD) and is printed on an Objet or Polyjet printer in layers which are set quickly with air blowers built into the print head. This is an acrylic material which is pretty strong, although quite brittle. This will print at a resolution of 16 microns- 0.016mm layers. It is not strong enough to be moulded from, so an intermediate silicon mould will be needed to make replica pieces.  Advantages: cheaper than other processes, can get good results with planning. Disadvantages: requires support material which can leave a rough, unpleasant finish. This can make models unusable. Can be waxy and difficult to clean. Brittle.

- High temperature photopolymer plastic: A 3D printing substance used in the medical and manufacturing industry, some versions of this material can be directly placed in a high temperature rubber mould, making it great for model masters. Printed using a laser system to set liquid resin, this 'grows' the model out of a liquid bed. There are several variations of this process used for differing applications. In the right hands, it will produce lovely, smooth finishes. However, it requires a lot of expert set up to manually place support rods which then have to be removed after printing- this is time consuming and expensive. This material prints out at 25 microns, but the surface finish means it can actually hold more detail than some finer prints. Advantages: Some polymers can be placed straight in a mould, excellent finish and detail. Disadvantages: Very expensive due to labour involved, will require manual cleaning of models before casting. 

- Jeweller's Wax: Used in a mechanical printer by jewellers and lost wax casting. Designed to be melted out of a fine sand mould by hot metal, but can be used to make moulds by cold casting the masters with silicon to make replica pieces. The wax print can get very good results and the process builds a support of a different wax with a lower melt point that is then removed with a heat bath, so there is no clean up when your parts arrive. This mastering process is already used by some very successful companies and I use it myself. Unfortunately, this material is incredibly fragile and some companies have given up on it simply because they couldn't get the stuff to their moulds! Advantages: No clean-up needed- as long as you know how to make your masters. Great levels of detail.  Disadvantages: very slow print process, fragile parts are an art in themselves to work with, still quite expensive for small models, very costly for larger pieces. 

Each has its own strengths and weaknesses and at this time, there isn't a perfect solution. My preferred system is the Photopolymer plastic resins, which get the best and most workable overall results. However, with an experienced casting team, the wax process can produce excellent results a little more economically. 

In the next post, I will look at how files are produced that a 3D printer can use, the software involved in making  and checking the file, as well as common things to watch out for when working in 3D with production of miniatures in mind. 




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