This article was originally published on August 7th, 2013 for the New York Video Game Critics' Circle site, where I was interning at the time. Geared towards individuals passionate about games, I composed a piece that covered the general 3D printing process, from idea conception to post production, through the cheeky lense of game terminology (at least, I thought it to be cheeky at the time). It was an enjoyable piece to write that I still think, after several years, can provide others wih a glimpse into what the printing truly entails, especically from the prodution side.
FYI, I did do an update to the article, but only to refine some of the thoughts that, with added experience, I can more clearly realize.
I hope you enjoy this throwback as much as I did! It was interesting to see just how much I have grown since that time!
*Photo credits to the LaGuardia Studio; Halo Spartan figure and video credit to Stratasys
How difficult is 3D printing right now? Will 3D printers be as ubiquitous as iPhones? Will they save the world? To learn more, the author asks that you think of 3D printing as a game — a slow game.
This is a 3D printed Halo Spartan. Pretty cool, right?
You have probably seen 3D printing being discussed as a bubbling under, hot new thing, and you sort of think you know how it works, but not really. Is it just stuff that spews out of just any printer, is it magic?
Well, to get a better idea, why don’t we play a game?
Step into the arena; you are now a player, working your way through a virtual world, an RPG if you will, that will eventually collide with reality!
Level I: Modeling
Let the games begin; it’s time to build our character!
But don't be decieved, modeling for 3D printing is not an easy task; the learning curve is curvaceous, specific, and completely different than modeling for animation. Unlike animated models, which only need to exist and function in cyberspace, our 3D printed model has to hold up in reality; it has to stand, bend, and/or withstand X amount of force, depending on how we see ourselves using it.
With that comes a few rules to play by:
A 3D model (in this case the Spartan) is made up of geometry, a series of polygons that fit together across the model and give it shape. In order to create a printable model, the geometry must agree with a series of specific and inflexible requirements-
An example of geometry in Zbrush; see that grid of squares? Those are polygons, and each polygon is made up of a face, edges, and vertices.
Top tentacle: Printable. Bottom Tentacle: not so much- the geometry is too pulled and distored, creating unprintable holes and extremely fragile geometry.
The aim is to create “closed geometry," forms made up of sides that have dimensional walls. A square is not printable, but a cube is, because a cube is not one-sided and is a three-dimensional shape.
Closed geometry is the foundation of printability, and as you work on your model, it is your responsibility to maintain it:
Holes in the geometry that the printer cannot read, inverted normals (when the geometry is essentially inside out), see the above image, and floating pieces of geometry not connected to the main model are signs of a unprintable model that if unfixed, means game over.
HOT MESS- unprintable with a captial U
This act is definitely easier said than done; from conception to export, breaking the rules is far easier than following them. 3D modeling programs are very overwhelming from both an interface and conceptual persective, and at points it can be very difficult to physically see problems with a model-
So be on top of your game ; errors can arise when the model is exported as a different kind of file, but the majority of issues come from unconscious modeling. If you, the player, is not constantly mindful of how you are stretching, rotating, and texturizing geometry, this puzzle of printability can quickly melt into a crumpled virtual ball, and repairing and fixing it can take hours on its own.
Level II: Initialize Printer
Level I complete — time for a boss battle!
After being exported as a file type readable to the printer (.stl, .obj, .wrl to name a few), your Spartan is uploaded into the printer software.
This is the proving ground—model versus software. It is the true test that determines whether you properly followed the rules. In the case of the Stratasys’ Connex500 printer (on which our Spartan was birthed), the model is “placed” on the print platform, and its printability is “validated”. Yes, 3D printing has its own lexicon, far easier to decipher than Al Behd (where are my FFX fans at!).
Level III: Printing
Level II complete — so sit back and watch the action!
A concept drawing of slices, whose thickeness are far thinner than what is shown here!
Once accepted as printable, the Spartan model will be processed by the printer's software in the form of slices, milimeters-thin horizontal cross sections that move vertically upward. These slices act as the building blocks for physically constructing the model. The higer number of thinner slices, the high quality the print.
The 3D printing process can be compared to the act of stacking paper sheet by sheet, slowly building up layers to create a fully formed object; the printer will first deposit a thin layer of material (plastic, powder, etc.) upon its printing platform, and will follow up by depositing atop that layer an adhsive substrate in the shape of one of the slices. This process then repeats, with the next layer of material fusing to the adhseive slice. Simultaneously, the printer also builds support material alongside the layers, disposable material that tightly surrounds the model. The material's title speaks to its purpose, for it not only helps the model keep its shape during printing, but it also helps protect and support any delicate or weaker areas of the model from deforming or breaking during the printing process, which generates dramatic drops in temeprature, elevation (as the print platform moves), and movement . This support will be removed in post-production.
Slice by slice, layer by layer, the printer begins to build our Spartan. How long it will take is all-dependent on the model's size, complexity, and the amount of material it will take to bring it to life. Some prints can take up to 72 hours to complete, but the Spartan would probably take a mere several hours to finish! If you think that’s too long, hey, new developments are happening everyday. Dot matrix printing of an image back in the day took a long time, too.
This slicing/layering process is a standard style of printing, and most of the printers on the market work in similar vein, but will differ in material and slightly in execution; each printer, of course, has its pros and cons, and one’s choice of printer can vary from project to project, level to level.
CHOOSE YOUR WEAPON
In a printer like the ZCorp 660, a white gypsum powder and a superglue-esque adhesive are used to construct prints with sandstone-like striations. This printer also prints in color, using CMYK print heads found in your (more familiar) inkjet printer.
The Stratasys Connex500 drops a layer of plastic material onto the print bed platform, then exposes the material to a UV light that solidifies it.
Like lasers? An SLA or SLS printer exposes a layer of liquid (SLA) or powder (SLS) to a laser light that moves across it in the shape of the slices (It looks like the Tron LightCycle!). The treated layer is then lowered into a vat of the material, where it picks up another layer to be zapped.
The trendy desktop printer Makerbot uses an organic PLA plastic (or stronger ABS plastic) that is heated and extruded through a cone shaped device. It also bloops and pings like an old school video game.
Level IV: Post-Production
Level III Complete- Let’s finish him off!
Whoa, slow down! Really slow down!
The world of 3D printing is nothing like The Jetsons, where Judy pulls her ready-to-eat hamburger out of the machine.
Once a model is printed, there is still a laborious journey to victory. From cleaning to sanding, post-production is a specific, time-consuming process that can take anywhere from several hours to several days to complete. It’s a common misconception; people expect the process to be lightning fast, and it just isn't.
Post-production on models can make or (literally) break the piece; this is the period where it all comes together, both practically and aesthetically.
Support Material: 0, Spartan: 9000
The model must first be cleaned of its support material (either sprayed off with air, tweezed off, or even power-washed) which, which can easily turn into a game of Operation; a steady hand and watchful eye are a must, for in this stage the model is at its weakest, for you are removing the very fortress that keeps it safe. This makes breakage or deformation at this stage common.
From this point onward, a multitude of decisions can be made in finishing. A model can be sanded, waxed, spray painted, dipped in Superglue, coated in resin, etc.; to not only achieve the final desired look, but to also make it stronger and more durable.
BAM!
Mission Complete!
With our game over in the best way possible, the post-play comes down to an element vital to game design: iteration. 3D printing was founded as a method of rapid-prototyping.
With each 3D printed journey you go on, with each failed or wonky model produced, your skills are honed, your understanding of the process clearer, and through emergent gameplay, you the player raises the bar creatively and technically one notch further. In this game, you compete with yourself, and all you have to do is accept the challenge to get started!
To conlude, the following video by Stratasys visually nutshells my text as they 3D print a Spartan on their Connex 500 machine.