The Meandrous Engineer

3D printing is one of the most powerful tools that makers have ever had–and it’s quietly making a lot of you worse at making. It has diluted the decision process that all makers need to go through.  The questions of how and why are always important for a project.  You are cheating yourself if you skip this step, and a 3D printer is the easy button that maybe you shouldn’t wear out so quickly.

Due to 3d printing’s flashy nature with abilities to make complex  and interesting shapes, there’s no doubt as to the reasons why its true applications have been massively over inflated through the years.  Just one casual browse of your youtube feed will show you how many unbelievable things have been made with 3D printers.  I do not contest that the possibilities are there, but there is a plague of over reliance happening that started at the inception of 3D printers years ago that contributes to over expectations for what can actually be accomplished.  Even the founder of 3D printing himself, Charles Hull, has said the technology has been overhyped in a generalized representation of a utopic future.

Have there been massive leaps forward in technology allowing us to make much more durable and high quality prints?  Absolutely.   

Are we using these prints in environments they probably won’t survive?  Also true. (Rocket raccoon reference of him saying “this is also true” for comedic effect)

The use cases are a lot more nuanced than “3D printing is crap” or “3D printing can change the world”  I just see many makers jumping into projects and the 3D printer is the gateway for them.  This is very understandable.  The barrier to entry for 3D printing has become very small, so it’s a logical step for the maker journey, but many never progress past that.  I think there is a self imposed barrier of material difficulty that keeps people from moving into other mediums like woodworking or metal working, but “metal is hard” shouldn’t be your excuse.  Learning other processes can open up your possibilities and even come back to inform your 3D print designs.  

I’m going to go through some of the reasons 3d printing is great and a lot of the applications where it’s just not all it’s cracked up to be. There are inherent weaknesses in 3d prints, and you deserve better choices.  

When the Tool Becomes the Master

Removes thought from your designs because the machine will make it for you.  

First off, 3D printers, like many things, are tools, equivalent to a hammer or a pair of pliers.  They are a choice within our arsenal to help us accomplish our goals for what we desire to make.  The problem is when the tool becomes the master when we think it can do anything we throw at it.

Yes, 3D printers can make complex shapes.  Whatever you can design in cad or borrow from Thingiverse can potentially be made real.  This is the trap.  This is the allure that keeps makers limited and trapped in the bog of one realm when there are many more worlds out there.  The main question that many makers skip is “Is this the best way to make what I need?”

If you do not ask this question, you are cheating yourself.  You must ask this question with every project.  Using 3D printers is the easy button for making something.  Yes, 3D printers require skill to design, slice, and print, but I worry that these things are becoming a crutch for makers who have yet to pursue other avenues like CNC machines, metalworking, sculpting, or more traditional skills like woodworking. 

Denying yourself the choice of different tools of making is one of the most limiting things you can do.  

The Removal of Authorship

The second main pitfall of 3D printing is the distancing of authorship for original parts.  We live in a world where many things that could be designed by humans are being stripped away.  Some would label it a convenience, but others would say that we are stripping away the very things that make those products human.  Which of those choices is better has yet to be seen, but one can argue that by not designing parts yourself, you are plagiarizing others’ work whether bought, borrowed, or stolen.

Drawing parallels to the existential AI arguments, this is both the beauty and the darkness about 3D printing where people take or buy the designs of others to print for themselves.  On one hand it gives people the ability to make things that they otherwise wouldn’t possess, but it takes the work of others who know how to design parts to provide the ability to actually get it done. This makes some users akin to microwave operators.  Being able to put something in and press start doesn’t mean you know how to cook.  This easy button does do wonderful things for the maker world by bringing in those who might have previously viewed making as difficult or impossible.  I know this is harsh and I want to be clear.  I want to encourage makers of all kinds to keep pursuing learning and looking for new ways to improve.  This is the whole point of this video.  I want to shock you out of complacency and pursue more because I know that all of you are capable of doing so.

Material Weaknesses

All materials have inherent properties with both strengths and weaknesses.  Some are great for impact forces while others reduce friction.  Using the knowledge of these properties is a great source for becoming successful as an engineer.  However, I would argue that it would be greatly helpful to the maker world as well.  Material science only has to be as complicated as you want it to be and understanding some basic ideas can help you choose the best material for your projects. 

That being said, I bring you to one of the main issues I have with 3D printing and it’s a problem you should be aware of as well.  ALL of the materials that are used in 3D printing like PLA, Nylon, ABS and others have a reduction in strength or qualities of up to 20-50% after being extruded into layers on an FDM printer. This has been documented and catalogued for us many times by researchers and people on youtube using decent methods of scientific experimentation.  

Basically the non homogenous structure that is created by printing in layers that may or may not stick to each other causes inherent weaknesses in the print and even when reorienting the layers you can still be victim to the weakening of materials.  Even in strong materials like titanium and steel, the geometry of a part plays a major role in its ability to avoid breaking in high stress areas.  Essentially you can boil it down to sharp corners are bad and rounded corners are good.  Sharp changes in direction on a part profile are akin to folding a piece of paper in half over and over which will allow it to tear in one line. Smooth changes in direction cause the stress to more evenly distribute throughout the material.  

So you might be thinking, I’ll just design my parts with fillets and it will be ok.  Right?

Wrong.  Every layer in an FDM printer introduces a stress concentration as the filament is extruded out onto the previous layer.  There is a little point on the inside of the layers that is a sharp point, akin to creasing that same piece of paper.  So even if you achieve that perfect recipe of ambient temperature, extruder settings, and slicer adjustments, you still will always have these little stress concentrations at EVERY layer.  You might could refine layer height so much that it is almost smooth, but at the cost of time and materials.  There are some industrial 3D printers that can print a nice smooth wall using FDM, but those are out of the range of the average maker.  I’ll touch on those later.

So what is this all dancing around?  It’s a term called anisotropy. Anisotropy is defined as the structural property of non-uniformity in different directions.  This term is from studying grains of materials such as wood or metal. All it means is that material is stronger in one direction than another. Many 3d printer users already know this and reorient their prints to the xy plane vs the z plane. Printing up through the z plane can reduce strength from the original material strength by as much as 50%. Printing in the xy plane still results in a reduction in 20%. 

So what does this have to do with you and why all the material science babble?  It’s all harkening back to what I said before. Your material choice matters. You have to know the sacrifices you are making when you blindly choose to print something. You have to always ask yourself if there is a better way for what you need. If the answer is no, then print away. The problem I see is that 3D printing is the easy way out. It’s the one size fits all if you don’t know how to consider things. It’s the crutch of your maker's repertoire.

False Sense of Efficiency 

One of the things that gives you a false sense of security is thinking that 3D printing saves you time by working in the background while you do something else. But we’ve all been there. Setting up an important print only to have it turn to spaghetti. Printing something mechanically critical only to have its holes too big or too small. How many times do you have to reprint something to get it perfect?  All the settings, tweaking, and design revisions just to get the perfect part. You could have learned how to make it from wood or metal and had it done in a fraction of the time with the right dimensions to boot. Machining, welding and woodworking may seem daunting to the uninitiated, but you can do so much more, so much faster if you give these materials a chance. 

The thoughts you may have of efficiency may just be a self delusion lost in the hours of painful tinkering. 

Redemption Arc of 3D Printing

So why do I say all of these negative things about 3d printing?  Someone has to. Your YouTube feed is a relentless hit after hit of “I printed this iron man suit” or “I printed this unbelievable thing”. 

I’m not here to take a dig at those channels because many of them go into the difficulties of the material process, but the effect it has on the maker community has become a mass delusion that 3d printing will save us all and I’m here to say it isn’t the savior it has been hoisted up to be. 

That being said, it IS a very wonderful tool that has numerous possibilities for enriching the utility belt of makers in general. 

There are constant advancements in this technology and I for one think that its boundaries should be constantly pushed so that one day, it might achieve our dreams. 

All of these statements are about FDM printers, not resin, laser sintering, or even some more industrial printers that have achieved levels of part quality that actually have a chance to survive abusive atmospheres. 

With the launch of the Artemis II, I am reminded that NASA has successfully employed 3d printing in situations for both the ISS and on the Artemis itself. Some people have spotted FDM parts on the footage in the background.  So it does have its place for certain uses. NASA is just simply a great example of judicious choices for when and when not to use 3D printing. Mostly to allow certain capabilities to solve problems in space when no one is there to help you but they can send you a digital file with a new CAd design to save the day. 

Like I mentioned before, there are industrial printers that have achieved more usefulness than hobby level 3d printers. I have used a brand called Markforged which uses a material called Onyx, which is a nylon impregnated with carbon fiber. This material is around $180 per roll,  but it is truly remarkable. The layer lines are nonexistent to the naked eye.  I have used a part in the coolant environment of a CNC machine for at least a year and half and it had no issues. The micro layer lines do still exist but these are the nicest prints I’ve seen in person. And this quality is for good reason. They are the price of a car last I checked. When/if this type of quality becomes cheaper for everyone to use, I will change my tune on many of my negative comments. 

What This Means for You

I say all of these things, not to be mean, but like I said before, to shock you out of complacency.  3D printers are probably one of the most accessible and versatile maker’s tools that are available today and you can do a lot with them.  There are the problems that I’ve gone over which are the over reliance on the machine, the lack of authorship, print durability issues, and delusions of efficiency.  It’s not your fault that the reputation of 3D printers is overinflated.  When every article and video is about all the unlimited possibilities of a machine, you can’t help but put all your efforts into it thinking it will be as useful as a replicator from Star Trek.  That’s literally the way they are portrayed.  They are represented as a do everything tool that will save us all, even on other planets.  And the possibilities are actually there, but for now they are merely the fevered dream of idealists who have not faced the realities of making and chaos that must be wrangled to create something of merit.  There is a skill that goes underdeveloped if you put all your efforts into 3d printing and that is the real crime here. That is the skill of making that is developed over a lifetime of working with your hands.  The constant learning about different tools and materials that eventually leads you to understand how the many ways of making are interwoven.  The tactile experience and understanding that you get by learning new ways of making and experimentation.  This is the learning that leads you to be able to answer the questions of how and why more intelligently when starting a project.  The vast amount of experience you can achieve that can tell you the best way.  And if your only tool that you ever choose is a 3d printer, you are robbing yourself of the maker experience.