What is 3D printing?


What is 3D printing?

by Katie Waller

3D printers are now widely available, but what can they print and how much do they cost? Read our expert guide to find out if a 3D printer is right for you.

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As the name implies, 3D printers print in three dimensions, but it’s their potential that makes them exciting. Rather than printing images on a flat piece of paper, they can print 3D objects and shapes using plastic, metal or even wood or edible food.

The most advanced and versatile 3D printers are used in industry, but more basic home 3D printers - that print in plastic only - are small enough to sit on your desktop.

Looking for a good 2D printer that’s cheap to print on good old-fashioned paper? Take a look at our Best cheap printers to run.

How does 3D printing work?

The object you want to print has to be designed first. Pre-designed 3D prints are available to download from 3D printer websites so you can get going straight away. The list of designs is extensive, but if you’re looking for a design that isn't already available, you can create your own designs on a computer using Computer Aided Design (CAD) software.

You don't have to buy expensive software for this either. Free CAD software such as Google Sketchup can be used to model your own creations. You just have to remember that prints will come through the printer from the bottom up, so tailor your design accordingly.

Designs are sent to the 3D printer, where they’ll be crafted layer by layer. Most 3D printers use heated plastic to create your structure, with replacement spools of plastic available in stores. Depending on your printer, it may be possible to combine colours and even material, and the process can take hours, depending on the required quality.

What can I make with a 3D printer?

Pretty much anything, from phone cases to screwdriver tips, jewellery and sculptures. There are limitations with a home 3D printer though. Entry-level models can only print in one colour at a time and you can only print items as large as the printer’s own space limitations allow.

The choice of materials available to print with at home is also limited, so don't expect to be printing off load-bearing spare parts for your bike just yet. Most printing materials aren't waterproof, nor are they particularly durable.

Should I buy a 3D printer?

In industry, the big benefit of 3D printing is the speed at which prototypes can be produced in three-dimensional form, adapted or redesigned and then printed again.

Home users, however, may find themselves printing novelties such as figurines from 3D print websites to start with. But the real benefit comes in the ability to create your own prototypes and see your own designs become reality. Aside from the initial outlay on the printer, prints themselves can be quite cheap to produce in terms of material costs for the plastic.

How much should I pay for a 3D printer?

The cheapest 3D printers cost around £300-£1,000, so buying one will set you back around the price of a decent 42-inch TV.

There will be ongoing costs for printing materials too - a spool of Makerbot’s printing plastic, for example, starts from around £30.

Where can I buy a 3D printer?

3D printers are slowly but surely creeping into high street stores such as PC World, but if you’re looking for a choice of brands and models then it’s best to shop online.

You can buy 3D printers directly from manufacturers such as Reprap, Cubify and Makerbot online, or choose from a wide range of 3D printers on shopping websites such as Amazon.co.uk.

Limitations of a home 3D printer

Materials: Many of the lowest-priced models are only capable of printing in one type of plastic and just one colour at a time, limiting what you can do with the print and how it looks. If you want to produce a multi-coloured print, models such as the Cube 3 can print dual colour simultaneously. Alternatively, you can with careful designing print different-coloured parts separately and snap them together later.

Strength: Prints are built up in layers, which will impact on the strength of the part. 3D prints may not be strong enough to bear some loads and stresses – this rules out printing any moving or load-bearing replacement parts for your bike, for example.

Surface finish: Print quality isn’t as good on a low-cost 3D printer. 3D printers that print by squirting out a string of plastic are the most common type, printing in layers around 200 to 75 microns thick. This gives a stepped look to the surface of the print. Entry-level models don’t tend to have heated print tables either, so the base of your print may curl a bit at the edges, depending on your design.

Print size: This is limited by the print area of the printer. On an entry-level model you can expect a maximum size of roughly 15 centimetres all round, depending on the exact model.

Ease of use: Some printers arrive as one unit, others you have to put together yourself like Ikea furniture. Setting up any home 3D printer can be tricky as we found when trying to get the print table level when we reviewed the Makerbot Replicator 2. As well as setup issues, it can take practice to get your own designs to print successfully. Most printers print from the bottom up and manufacturers are continually developing their software to pre-empt issues when turning a design into a print.

Would I be better off using 3D printing services?

The benefit of using a 3D printing service is that you won’t have to splash out upwards of £500 to get started printing your designs.

The finish is likely to be better - because most use a professional 3D printer - and if you’re just starting out, some can also check the layout of your design to make sure it will print successfully first time.

However, you will have to wait for your prints - rather than having the convenience of printing at home - and some services have a minimum order cost which is no good if you just want one little print.