A 3D printing video from National Geographic went viral on the interwebs last week and quickly generated some controversy among 3D printing enthusiasts. In the video, physicist David Kaplan visited ZCorp HQ to “find out whether they can print a crescent wrench”. Kaplan was shown a selection of amazing items printed on ZCorp devices, including multicolored objects with moving parts, as well as the standard explanation of how 3D printing actually works.
Then the interesting part occurred. Kaplan’s substantial wrench was put under a hand scanner, capable of capturing highly detailed 3D information. It then appeared as if this captured data was then converted into a proper 3D model, “creating an image that will be sent to the printer”.
Then, just like you’d see on a TV cooking show, the printer was opened and a printed wrench was extracted from the powder. While the wrench was demonstrated to be strong enough for actual use, questions immediately arose.
We’re wondering how a hand scanner can discern moving parts, such as are found in a crescent wrench? We know of no technology that could do such a thing, particularly when the video showed no part motion during the scan. Viewers were left with the impression that you could simply wave your scanner at anything and hope to replicate it immediately – including hidden internal moving parts, and by extension even electronics!
That’s just not possible. This was noticed and challenged by several sources, including on Jon Udell’s blog, where a discussion erupted (link below).
Scan captures are usually nowhere near printable state, and always require at least minor if not major editing and conversion before printing can be attempted. Worse, a given object’s geometry might not be printable on a given 3D printer – the right 3D print technology must match the object.
Providing general awareness of 3D printing is a good thing, but leading people to unrealistic expectations is not helpful. We fear that a growing abundance of such memes will eventually cause a backlash towards 3D printing, as folks will soon discover that you can’t simply replicate just anything.
Correction: you can’t replicate just anything – yet.
I cannot count the number of people that have called or emailed me in regards to this video. One of my videos is a "related video" on Youtube and that is why I've been getting all kinds of calls and emails.
This video is definitely very misleading. Most of the video is excellent, but the scanning of the wrench is the misleading part.
The good news is that this video has generated lots of BUZZ for the 3D printing community.
I wish I was a Zcorp dealer right now… I've been finding myself saying this a lot recently "Sorry I don't sell 3D printers."
Bradley
Print To 3D
The critique of the video is absolutely fair. There is significant amount of post-scan process and modeling that was left out, and the end result is that an unrealistic outcome is presented factually. It's not a good practice to do this, but for storytelling, I understand why this essential part was left out.
I feel the effect of the video was however to create a faulty understanding of the real process.
David Kaplan made a follow-up response video about the controversy here: http://www.youtube.com/watch?v=1yt8ZZGFkFc
We don't think our post was misleading at all; the point was that the vast majority of viewers of the video were left with an incorrect understanding of how things work. The otherwise excellent video was ultimately misleading, through no fault of ZCorp as it was edited by NG's videographers.
We totally understand the process that obviously was actually used to prepare the wrench for what appeared to be a very successful print and that the ZCorp printers and scanners are terrific machines – but the video simply didn't represent the capabilities and process properly for the general audience. We can't count the number of people who pointed out that video and now mistakenly believe that anything can be replicated.
If 3DP videos should go viral, we're hoping they leave people with a more realistic understanding of what can be done today.
Viewers wouldn't have felt misled if the video had merely shown the video being taken away (to be scanned) and shown the replicated wrench being brought back. But the video disclosed many interim steps, leading many viewers to assume it disclosed the entire workflow.
That just seems to be human nature: the more details you disclose, the more listeners expect your disclosure to be exhaustively complete. Such an expectation can come as a nasty surprise to a presenter, who honestly thought they were just omitting esoterica to keep it simple.
Well then remake the video showing the captured scan, the entire editing process
, then print it (without re attempts) then people might start to believe… Don't edit the video of the weeks of editing…:)
No controversy really,except those created by Z Corp competitors. Your post is misleading. It correct that ZScanners cannot scan the internal details of the wrench. It is a laser based scanner that can only capture surface information within line of sight. Details like the ends of the worm screw in the wrench are created digitally between scanning and printing as one of the edits mentioned above. The scanner captures everything that can be seen and then someone using editing software adds the details that are hidden. (Alternatively, one could separate the pieces and scan them separately.) the 3D printed wrench is slightly different from the one we scanned. The differences between the original wrench and the printed one were done intentionally to demonstrate that once scanned, geometry can be digitally edited and then printed. This is typically done in software packages like Geomagic and Rapidform or even in CAD packages like Solidworks. Our customers will typically add, remove or edit features of the design before printing (check out the other videos on our website or on YouTube). In the interest of time, the editors cut the explanation about digital editing from the final video. For an accurate outline of the technology from the Z Corp employee featured in the video, see his blog:
http://mcad3dprintingandprototyping.blogspot.com/2011/07/product-replicator-real-or-fake.html
This is the first real NG paid ad! When I first watched it, I was stunned by it
being a complete let down of NG's normal high quality reporting. at the very
least NG could do was preface with "the following is a paid advertisement
from Zcorp".
Also, several people have email "Can you really do that?" Of course not!
was my reply! …. O