Unrealistic expectations about 3d printing
 |  Igor Idzik

Misconceptions about 3d printing

That you can print anything you want.

Limitations

3D printing has lots of things it can’t do, just like any other tech. People always seem to get this idea that there’s limitless potential out there, and all we need to do is invent the right upgrades.

In reality, different types of printers have different types of objects that they can and can't print, and no amount of invention is going to make that go away.

The best example I can think of is overhangs on FDM printers. Check out the printing error on the front window of this boat:

That happens because a FDM printer has to build material up from a solid surface. If a part of what you’re printing is just hanging in midair, then there’s nothing for the printer to build up from, and the material it’s trying to place just droops down in midair.

Here’s a test-print that someone did of some different letters, which shows it off better:

That's not how it works

My usual response is just “that’s not how that works” - because the print-anything-box they're imagining in their head isn't real.

The press and hype

It doesn't help that press releases talk about different printers like they’re facets of the same technology. It gives people the idea that they're interchangeable, or that we can combine them into one machine. In reality, they're often completely different manufacturing processes, working with completely different materials, and they aren't compatible with each other.

A 3D printer isn’t like a replicator in Star Trek, and it’s not going to be. A single machine that can instantly make whatever you want is science fiction.

Real manufacturing technology has limitations.

The price

Mostly, the price expectations. People want highly detailed prints, preferably in color and are often a bit surprised that they’ve spent over $100 for some 3D printing service only to find that the final result isn’t what they expected. Say, for example, this 3D print of a model I call “Ruby”:

The original model (top-right)was colorful and looks nice. But when you remove the color (bottom-right) then you will notice some details disappearing. The final 3D print (left) at 20 cm tall looks good because the 3D printer used uses a small voxels size. It still doesn’t look polished, though. It’s a rough surface and polishing will actually destroy some of the finer details.

Still, with proper 3D printers you can even make interesting colored 3D prints in colored sandstone like this one:

Problem is, this sandstone print is a bit expensive at €93.46 (over $100!) for something the size of the average toy. It is also quite fragile as especially the horns and tail can break off. These things are not really toys because they’re expensive and a bit vulnerable but they still look quite nice. Yet you can buy similar figurines in a toy shop for a tenth of the costs of having them 3D printed.

Expensive!

And there lies the main problem! Printing in 3D is expensive! And even while the costs of printers and PLA is dropping, there are still cheaper methods to create 3D objects than by printing them. One trick I once used was to have a simple model printed in 3D and then I used silicone to make a mold of this figurine. I could then use gypsum to cast various new figurines with the same shape and size. (I could also use resin to cast those figurines but resin is a bit more fluid and my mold had too many leaks…)

Production

So if you want to start mass production then 3D printing is a bad solution. Not only is it slow but it’s also a bit expensive. It is a great way to make prototypes and if you look at shops like Shapeways where they sell 3D printed objects in all kinds of materials including metals, it sure has a good future.

People are expecting 3D printing to become a lot cheaper and to have much better quality. After all, many people want to print all kinds of figurines as toys including having themselves and their pets printed in 3D. But most don’t realize that the costs for such prints are easily between $50 and $100 if you use an external party. And if you try it at home on your own 3D printer you will discover all kinds of technical issues including the need for adding support beams to your model, increasing the amount of PLA you’d need and you’d still end up with an object with a rough surface. Price and quality are still far off in the 3D World. Most home printers seriously lack good quality. Most high-quality 3D printers are expensive and most 3D printing services tend to be expensive even if they provide good quality.

And the size is also important. That Zuniceratops was over $100 and still is smaller than my hand.

(Also important: 3D prints tend to need support to make sure the model doesn’t collapse while printing. This often means that very thin or small details might not be printed correctly.)Also weird: I just changed the size of the Zuniceratops to 13.8 cm long and it’s become a lot cheaper. Still €31.63 though… Three times more than a plastic toy of the same size and more breakable…