Once upon a time...

Twenty years ago, 3D printing was a little-known industrial device. Using laser cutting heads directed by a sophisticated computer, layers were removed from a block of special plastic to create three dimensional forms to serve as useful models before mechanical components were produced out of harder and more expensive materials. Somewhat like early computers, the machines were bulky, expensive, and largely used for industrial processes.  

Twenty years down the line, and now we have 3D printers as cheap as a desktop computer, more versatile, and on the verge of turning from hobbyists’ toys into home appliances. According to one source, it is likely that in ten years people will be buying food printers that will prepare elaborate dishes and desserts, perfectly. Every time. All one would need to do is replace the printer capsules, which add layers of the different ingredients according to a program - much like replacing the colour cartridges in a home printer, really.

Magic? No, 3D printing

Before discussing what can be done with 3D printers, a few words on how they currently work and will work in future. 3D printers have one or more heads that spray a thin layer of fine material onto a base or lower layer.  A laser head then fuses the material into the designed pattern.  Additional layers gradually build up to form a complete, complex three-dimensional form.  If there are several print heads (as in an inkjet printer), each head can spray a different material or colour to create complex, multi-material shapes.

The industrial advantages are obvious. Rocket and jet engine components, which usually require expensive grinding and processing, are simplified, quicker to make, and more reliable. On the other end, small 3D printers can be used to print bone matrixes for bone replacement therapies and elements of heart and other surgical implants. 

In theory, at least, most industrial manufacturing processes for mechanical, chemical, and electronic components can be performed by 3D printing rather than traditional melting, forging, grinding, hammering, and so on. As time goes by, it will become possible to complete more such processes via printers, resulting in savings in cost, labour, and raw materials. Sprayed material that has not been fused can be reused, the laser heads produce very accurate copies at low cost, and labour would consist of supervising banks of printers.

3D printing has the capacity to radically change the shape of the world we live in.

Advantages in the home are less obvious, but tangible nevertheless. Initially a tool for hobbyists, 3D printing and the swapping/trading of software files for the manufacture of specific objects have become a major element in the “Maker Movement”, a social network and community of those interested in designing, developing, and self-manufacturing various items for use or show. The Maker Movement, which has grown into worldwide phenomenon since about 2005, has embraced 3D printing technology as members recognized the potential of 3D printers to achieve their goals very early on. The current development in 3D printers and their future trajectory are bringing more and more interested actors on board.

A Spanish university recently announced the development of a 3D printer for food capable of printing complex food shapes using four different foodstuff printer capsules, each layer gently cooked by a low wattage laser. The printer can produce cakes, puddings, pizzas and many other foods, depending only on the right programme and the right ‘ink’ or capsules filled with foodstuffs. The prototype had the capacity for four such capsules, which could be swapped out for different foods.

A success multiplier for poor states 

Looking at the broader picture, 3D printing has the capacity to radically change the shape of the world we live in. Consider the cost of a small water pipe needed to fix a leak.  It comprises the cost of raw materials and transport to the manufacturer, manufacturing costs and transportation to the retailer/wholesaler, plus transportation costs to the end user. All these mean a 1 meter section of ½” pipe costs around 3 euros.  Cut out all the middlemen, however, and the same quantity of pipe (raw material plus transport plus home printing) costs a fraction of that price, perhaps 10-20%.

To examine this in a bit more detail, let us consider water. River water is generally contaminated, and people who drink it suffer from recurring gastric and eye problems. Well water requires a well and a pump, ideally some form of storage for the water, and faucets to allow access. All these parts are largely made of metal. Replacement parts are needed when the originals wear out, and are almost always manufactured in developed countries. This means that the expense of repairing pumps, pipes, and faucets as they wear out is beyond the ability of locals. 

Small 3D printers will ultimately allow freedom from the invisible domination of developed countries’ economic interests over those of communities in LDCs.

A 3D printer and a single computer accessible to an entire village would make it possible to replace the missing parts and ensure clean water is constantly available. This sets off a chain of positive effects: available fresh water means women and girls do not have to travel far to bring back small amounts of water on their backs. Community health improves, lowering expenditures for treatment and increasing work and school days. No less importantly, success breeds success.

It is highly likely that locals, wherever they live, will find more uses for 3D printed objects than we in our comfortable industrial world can imagine, and the 3D printer will be used to leverage flexible, appropriate, locally-owned development. Moreover, the presence of 3D printers, like the mobile phones that have done much to transform economics, civil protection, agriculture, and other facets of life in Africa, is likely to have unforeseeable positive consequences. Perhaps the most important thing is that small 3D printers will ultimately allow freedom from the invisible domination of developed countries’ economic interests over those of communities in LDCs.

And here's the snake....

That was the good news. Now for the bad: Humans have an interest—either perverse, or genetic, depending on one’s point of view—in producing weapons. Unsurprisingly, one of the early uses of home 3D printers has been the attempt to produce homemade guns and ammunition. Despite claims made during the massive media exposure in 2013, the first working pistol, the Liberator designed by Cody Wilson in the US, is not a weapon. It can fire a single .22 bullet after laborious loading, and is worthless after a few shots. Even the Free Open Source Software & Computer Aided Design (FOSSCAD) internet society’s freely available designs have not been fully tested.

A fully automatic, war-capable weapon is perfectly feasible.

Only parts of weapons, most notoriously the ‘receiver’ (the part of the weapon that holds the barrel, trigger assembly, bolt, and magazine together) can be printed. More and more designs are now available, and one can easily find demonstrations of firearms with 3D printed parts. A fully automatic, war-capable weapon is perfectly feasible. As someone who deals with firearm control on a daily basis, I would expect most professionals could design such a weapon with little problem, but given that the world is awash with small arms, it is unlikely to make a difference.

What is the problem then? Virtually all firearms sold today have an identifying unique serial number imprinted on the receiver. This is used for forensic purposes to trace firearms involved in crimes. A homemade plastic receiver means that such tracing would not be possible. To add to the problem, weapons made largely of plastic may be invisible to detection devices such as those used in airports, and thus present a danger to air passengers.