3D Printing Problems and Nice to Haves

[jdm82]

Thanks for taking the time to visit this post. I'm a newbie here and to 3D printing in general. My background is in Aerospace and one of my graduate degrees is in Materials Science. I'm here in part to learn more but also to explore my entrepreneurial itch. I've assembled a team of other mechanical engineers and materials science guys to start tackling some problems we've encountered. I would also like to dabble in this arena. So I'm here to ask what problems you guys see that could be solved? Or to phrase it a different way, what sucks about 3D printing? Any help is greatly appreciated. Thanks.

[awerby]

Most of the low-end hot plastic extrusion 3D printers we get to play with have some problems in common. They rely on plastic parts which tend to fail in use. They have trouble leveling the beds to be true to the geometry of the mechanism and staying level. The mechanisms tend to be light-duty assemblies that shake a lot. They all rely on the same arcane but open-sourced software that doesn't work very well, or very intuitively. The parts they make often require support, but the support generation tools are flaky, and the supports themselves are difficult to remove. The filament reels that feed them tend to get tangled, which causes them to stop feeding in mid-print. The plastics themselves tend to absorb moisture and then behave badly because of it. The extruders tend to clog up and stop working, or else they spit out material randomly and make a mess. The prints themselves tend to warp, and often have difficulty adhering to the build plates. And their detail resolution and surface quality leave a lot to be desired.

You could think about diving in and solving all these problems, I suppose. Or, given that you've assembled this team of entrepreneurial engineers, it might be better to leapfrog over these problematic but ubiquitous FDM-style printers, and explore something entirely different, like metal printing via laser sintering or electron beam melting. Supposedly some key patents to this technology have expired recently, and a new generation of SLS printers at a radically lower price-point are eagerly anticipated. If you could deliver a low-priced machine that could print in metals or other materials without added support being necessary, using inexpensive feedstocks, you'd be a big hero around here.

Andrew Werby

[jdm82]

Hi Andrew,
Thank you for the reply. That is a lot of good information and more than I was anticipating problem wise. I proposed a project to begin working on for added material adhesion between layers that piqued the interest of my chemist coworker. I'm a little surprised about the light duty assemblies, I mentioned to a friend that I thought the move in these areas would be more into the CNC type realm. I could pretty easily come up with that design and probably an evenly heated plate (I've heard that was also an issue) but the software and coding is way out of my wheelhouse.

The sintering challenge does seem interesting. I'll have to explore this more. The machines were quite expensive when I looked into them so I can see that there might be a home / business application.

Thank you, I appreciate the feedback.

[CaptainObvious]

All mechanical problems are not that difficult to solve, IMHO, the mayor hurdle remaining for FDM is the materials used to print, there's no perfect (or reasonably satisfactory) choice.

PLA is close to perfect in terms of printing, extrudes easily, no need for a heated bed, very little shrinkage, very good layer adhesion, but... it doesn't have good stability, it deforms over time under load and at relatively low temperatures (60C) it turns to bubblegum.
Besides that there are two other important advantages to PLA, first that it is not based on fossil fuels but renewable sources and second that it doesn't emit toxic fumes as most other filaments when printing, which makes it much more suitable for home use.

ABS prints quite easily, has good mechanical properties but requires a heated bed and that's not even enough to solve the big issues with shrinkage it suffers from, specially since layer adhesion is much poorer than PLA leading to delamination of the layers.

I've tried HIPS, it is similar to PLA but without the deformation and low temperature issues, however it has even weaker interlayer adhesion than ABS.

Nylon and PET are, AFAIK, the strongest materials, with great dimensional stability and interlayer adhesion but... you can't glue anything to them, in particular Nylon, which limits their use , for example I use 3D printing for airmodels, and not being able to glue some pieces together is a no starter.

IMHO a PLA with higher glass transition temperature and mechanical stability would be the Holy Grail of FDM

[jdm82]

Thank you for the response, I appreciate it. I'm discussing these items with my team and hopefully we can get some solutions going.