Casting is the process of creating metal objects by pouring liquid metal into a mould. In the context of tabletop games, nearly every metal miniature you'll use was cast. In ye olde days of wargaming, models were usually cast in lead alloys for their malleability and relatively low melting point. Changing views on the safety of such materials has seen manufacturers move to lead-free alloys since the 1980s, most metal models nowadays being made of tin, aluminum, or silver if you're feeling
classy pretentious and expensive.
This is an example process for metal or resin casting:
- The sculptor creates the master model. It may be called a "green" if it was sculpted in Green Stuff.
- Once the master is fully cured, he places the model in a box and fills the box with a different, molten material.
- Once that material is fully cured, the sculptor carefully splits the case in half, freeing the master sculpt from the brand-new mould.
- The sculptor cuts channels into the faces of the mould to allow injection of the casting material. Careful attention must be paid during this process to ensure the material will completely fill the mould, otherwise casting errors will be inevitable.
- The injection may commence and models will soon be in abundance.
Imperfections and Dangly Bits
There are three major side effects to the casting process: vents, flash, and mould lines. Vents are the dangly pieces on a metal or resin model that you can quickly nip off with a sharp knife or a simple twist and exist to allow excess material to overflow safely and air to escape during the injection. Flash occurs when the casting material squeezes between the mould's halves, leaving a paper-thin surface between the gaps in the finished piece. Mould lines occur when the two halves of the mould aren't perfectly aligned before casting. In some cases, they're subtle and easy to file down, while some can be so bad the model looks like one face has jumped half a scale meter to one side without informing the other face.
There's really no excuse for bad mould lines on metal models passing quality control when they can simply be melted down and recast. Resin, on the other hand, cannot be recycled in the same fashion, so resin casters need to hold themselves to a higher standard of quality (Quality, you say?).
Mold Wear and Tear
Due to the nature of the the casting procedure, a mold often cannot be used forever. For multiple reasons (going from costs to ease of making to having a mold with enough detail) the mold is forged from an alloy that is designed to withstand the temperature at which the liquid plastic/pewter/... is injected but not much higher. If a delicate balance is not maintained while casting/molding the miniatures, the mold will warp, crack, or generally lose detail (Something known formally as "thermo-mechanical fatigue" for anyone who'd like more info). Even when all possible care is taken, molds just don't last forever (nobody has yet told Airfix this). Model makers use several tactics for working around this:
The first and most straightforward is simply recasting the mold. More often than not, the "parent model" will be put in reverent storage and won't be melted away like in so-called "investment casting". The parent can be used to make more molds as needed. Sometimes, however, the parent is considered too precious, so a first-generation "daughter" model will be cast in the toughest stuff the model makers could possibly use (sometimes at the expense of the original mold) in order to make a very durable model which can be used to cast molds over and over without warping.
The second tactic is making a stronger mold that can withstand much higher temperatures. Sometimes the mold will get a mold made of it, and then that mold will be used to cast stronger molds which the models can be forged in without warping the mold. This method quickly becomes a lot more expensive, though.
This was the excuse for Man O' War being destroyed by GW.
Games Workshop and You
Games Workshop is a wargame company known for making egregiously overpriced models. If you didn't know that, you are obviously new to this wiki. They often excuse their prices by saying that their models are of exceptional quality and thus their molds are more expensive/break more often/need maintenance, despite that by industry standards (and as every single fucking 40K fan knows), Citadel miniatures have chunky details and low part counts, and price basic plastic models in the same range as top-of-the-line multimedia kits made for accuracy fiends who masturbate with digital calipers. And that's not even considering the fucking bubbles.
Casting can be expensive or cheap, depending on how you do it. A comprehensive fa/tg/uy-written guide is available to help you through the process.
As a side note GW likes to flail around its net-site, claiming that it's illegal to take any and all copies of minis and make conversions. That is legally bullshit, since that argument is only solvent in accordance to the country one is living in; in some European countries, for example, you are allowed to make as many copies of anything you have bought as long as you aren't selling or otherwise distributing them. Also, both Codecies and White Dwarf articles loved to show off kitbashes and conversions back in the day, so it's not like they can even claim no precedent. This gibbering madness has died down under the New ManagementTM, but who knows for how long.
3rd Party Modellers
While Games Workshop may waffle back and forth regarding what is and isn't "tournament legal" and "legal legal", one thing that hasn't wavered since the early 2000's are the 3rd party model sellers. In fact, they've grown in quality and quantity over recent years! These guys operate in the dubious legal grey area surrounding knock-off models, and will sell "Warhammer-inspired", "27/28/29/30mm-scale", or "totally-not-Warhammer" models designed from the ground up to fit in with the rest of GW's product lines.
These 3rd-party kits often come in the form of body parts or bits blister packs, an area where GW has been found wanting for literal decades, which are not-too-shockingly compatible with extant Warhammer Fantasy and Warhammer 40,000 models. These can take the form of whole packs of off-brand future-soldiers, or just sprues of disembodied limbs or weapons. Some 3rd party model shops specialize in fulling gaps in GW's product line, making models that strongly resemble units or armies that get no official love. Almost every one of these retailers have their own game system for their models, which everyone who buys their models plays. Some of these sellers specialize in one-model showpiece kits, to "count as" various Independent Characters on the tabletop. These full models can be as good as GW one-model kits, but not all of them are, so buyers beware (not that 1d4chan endorses buying these models for use outside of their original games). The 3rd party model makers generally operate above-board, until they overstep their legal bounds and GW kills them good and hard.
The casting techniques used by these guys varies widely, since none of them are as high-volume as Games Workshop or as high-quality (varying mileage) as Forge World. Some make metal models, some do resin, others use plastics. They will use any technique under the sun, or whatever is easiest.
Professional Recasters (aka bootlegging)
Some businesses in China will mass-produce recasted sprues and sell them on eBay, undercutting the original manufacturer by virtue of not having to pay scupltors for model designs. This is called bootlegging, and it is fucking illegal. On the other hand, fa/tg/uys who are enraged by GW's marketing bullshit and hideously overpriced models (but don't have the time, money, space, or skill to home-cast models) will turn to these sellers to get their model fix without feeding the beast, much as /v/irgins will pirate good video games that are held hostage by greedy or otherwise odious publishers. As a result you can expect to see some of the same skub regarding buying from "based Chinaman" as you would see regarding the ethics of pirating video games.
Of course, given that GW has been price gouging their customers (and underpaying their artists) for decades, the whole morality argument is very, very weak (and generally advanced by professional busybodies). Most people who actually buy recasts do so because they would otherwise be priced out of the hobby entirely, and either generally operate under a "don't ask, don't tell" policy...or don't care because, you know, it's a game marketed to children.
Most people who engage in kitbashing, scratch-building, and 3rd-party part-mixing will generally regard using re-casts with disdain. It would be like going to an auto show and announcing the replica Corvette you bought was a real Corvette, as opposed to driving up in a mock-Corvette you made yourself and announcing it as such. In any case, 1d4chan cannot provide any information regarding the purchase of recasted miniatures. Don't even think about it.
"And it was foretold in the book of The Second Machine Age that like a rising star a new science will come to be, and all men across the globe may print their miniatures, at affordable prices, forever ending the rule of the old powers and starting a new age of wonders."
- – Technoprophet Anonymus
This is GW's nightmare come true, the Doom Made Manifest, the Great Equalizer. 3D printing is a method of accurately fabricating objects using a 3D printer. 3D Printing works from a digital blueprint of the object in question, loading the material it will use, and then it fabricates the desired object before your very eyes. Originally, 3D printing was restricted to industrial purposes because of its sheer size and cost. By the 2010s, the costs have come down to the point where 3D printers are commercially available to the regular consumer and are relatively easy to understand and use, so even regular neckbeards like you and me could manage to use one. Printing a model is as simple as getting your hands on a 3D printer, its printing medium, and the file of the model you want. Dont think that means you can create your own army without subjecting your financial status to GW's pricing horrors: copyright laws still apply to 3D-printed likenesses of miniatures and you will get your ass sued for doing it (although do note that the same can apply for pirating multimedia and software from the internet, and how many times have you been sued by the developers for being a filthy pirate? Basically, don't draw attention to yourself by doing something dumb like selling it through popular retail channels, or anything that would draw the direct ire of GeeDubs themselves.)
What makes 3D printing so cheap is that it cuts production down to one step. Rather than following all of the steps above to make a model by hand, a 3D printer does all the hard work for you. Further, a 3D printer means you don't need to spend money on molds; if you've ever wondered why Forge World is so expensive, one part of that is because resin is cast differently to plastic, so the molds wear down faster and have to be replaced more often. That's not really a concern for us neckbeards since we aren't making ten thousand parts with our garage-casts, but for a manufacturer it is a notable expense. On the other hand, a 3D printer works from a digital master and has no need for a physical mould. Without a mould, there's no chance of all sorts of problems that injection casting faces. Lastly, a 3D printer uses much less material; models don't have to be cut for sprues, interiors don't have to be solid, and
there's no injection nozzle to which material can stick AHAHAHA, there totally is, but that is a negligible expense in both forms of production.
While your imagination runs wild, keep a few things in mind while thinking about how many Mk2-Armored Space Marines you want in your army compared to how many Mk.6's. Even as of 2015, 3D printers are still quite expensive, at least several hundred dollars for a printer of any quality (or a seed printer if you want to print more printers). Printers use spools of plastic feed, glues, or several kinds of urethane powder, which can all limit the materials available for your models. The last thing you want is your glue melting your Fire Prism or not adhering to your Warjack, and let's not even talk about paints. Also, all that plastic is expensive; not GW expensive, but still notable. Unless you are so seriously addicted to your plastic crack that you know every kind of commercial plastic by heart, you might want to do some research to figure out which printers can use what plastic before you buy. And most importantly, as of 2016, 3D printers that a fa/tg/uy could buy can't print at a high enough resolution to look good at 28mm scale by any stretch of the imagination. If you thought OG Finecast was bad, making a 3D print of anything tabletop-scale on a current printer is laughable. It's gotten slightly better since then, but the best 3D printers for the job are still far too expensive to be used for mass-producing minis. And don't forget about the copyright issue. You are not ChapterHouse Studios, and you are much more likely to lose your court case than they are. For the time being, the downfall of GW due to widespread 3D printing is little more than a pipe dream.
2018 update: Several 300-500$ price range 3D-printers exist, that can produce tabletop-quality miniatures with the proper settings and materials. And while it still requires some time investment and thought (or at the very least, googling some good settings for your system) on the user's part, it's already feasible. GW can lube up, since free and open databases for 3D model files already exist.
Expect GW to get into the film/vidya gaem sector much more heavily in the next decade or so.