3D Software

How to use computer aided engineering to improve a 3D printer

This month marks five years since I seriously got interested in 3D printing. I was a post-grad student who has been hearing about this great technology for a couple of year. It seemed like a thing taken out of science fiction- a machine that allows you to make whatever you want! All the ideas could materialize after few moments of printing. The perspective was very tempting. Some people have it in their hands- they are the Michelangelo master sculptures, clockwork geniuses like Hook or persistent inventors like Tesla. Well, I was good with computers and the concept of the machine doing the actual manufacturing was a dream come true.

At the same time we all know that dreams need something more than just sheer will to materialize- you need work and you need money. Even today, when the prices of 3D printers are getting to an affordable level, getting one might be a noticeable burden on your budget, especially for young enthusiasts.

On that day five years ago, the final barrier that prevented me from getting to the world of additive manufacturing was lifted- I learned about RepRaps. Make a printer that prints itself- at least the most “complex” components, and get the rest of the “simple” elements from your local hardware store- the game was on!

Pawel and his optomized RepRap 3D printer
Pawel and his optomized RepRap 3D printer

Of course the whole printer construction process was not that straightforward. The first question was: where to start? Though mechanical construction would most likely be like playing with lego’s, getting the wiring, electronics, power, and finally- software were tasks that seemed quite intimidating. This was the moment I truly experienced the very core strength of open-source. All the materials were there- you just needed to look and ask for them. Dozens of talented and dedicated engineers share their experience and expertise online with anyone who dares to look and ask for it.

Things in the RepRap community are always moving- new printer designs are presented, new improvements see light of day and horizons that seemed so far away get closer and closer. One of approaches taken by the community is using is the ever growing availability of numerical simulation tools.

With the use computer aided engineering (CAE), RepRap designers could take a leap forward in their journey to making their printers perform better. Although open-source printers are relatively cheap, having a trial-and-error design process is not optimal. Every prototype iteration that could be avoided is a save of money and time. In this regard, thanks to finite element analysis we could check if the designed plastic elements of the printers would hold the loads and withstand the stresses imposed on them. Vibration analysis allowed to determine areas undergoing periodic loads which could result in, for example screws getting loose, or worse- our 3D prints getting distorted.

Simulation of the heat distribution inside the extruder of an FDM 3D printer.
Simulation of the heat distribution inside the extruder of an FDM 3D printer.

Another key element solved by CAE approach was the heat control in the printer. Having a non-disturbed temperature at the print bed is a key ingredient in obtaining a good result. With simulation tools we can now precisely investigate the thermal behaviors of the hot-ends. We can simulate air flow over print beds to determine if temperature stays at desired levels. We can even investigate the influence of pritner elements on the thermal balance of the system: do the motors overheat? Do they affect the mounting points and can cause them to bend?

Deformation and vibration response of the frame of a RepRap 3D printer.
Deformation and vibration response of the frame of a RepRap 3D printer.

RepRaps today become better and better thanks to the use of computer aided engineering. I highly encourage you to enter the world of RepRap 3D printers is the place to go if you are looking for an engineering adventure. Even if you will have to put it on the side since your kid should not breathe plastic, you can keep involved designing new objects that one day you will print, or using simulations to make sure that the next version of your printer will be the best one ever.

In the case you want to learn how to leverage simulation for your own 3D printer designs you should join the free online workshop series organized in collaboration with SimScale.

During the three weekly sessions, the participants will learn the fundamentals of engineering simulation/CAE and will expand their knowledge by improving the design of the RepRap 3D printer.