Dear Colleagues,
As you well know – everyone is jumping onto the 3-d printing bandwagon. We purchased one in kit form a month or so ago. My two colleagues, Steve Steyn and Kim Li specified and assembled the printer together after some pain.
As we have discussed in earlier blogs, it is now possible to undertake 3-d printing of items ranging from phones to instrument cases – printing one layer at a time. This is possibly the prelude to a personal manufacturing revolution where everything is done on the fly anywhere anytime. Not in a low-paying sweatshop as is often the case.
But there are a few challenges which Steve Steyn, our very able staff engineer, has elaborated on below.
Challenges with 3-d printing
Complexity of assembling the machine:
All the parts were shipped in neatly numbered bags, making assembly straightforward. However, the written instructions sent with the kit were in German, prompting us to use the online English user-manual. After countless hours of reading, assembling, shaking, and cursing, the printer was assembled. We had to take it halfway-apart, twice, just because we missed one nut, or piece of wiring.
It clearly tests ones’ capability in all fields of engineering, from mechanics, to electronics. Nonetheless, it was assembled correctly. You do need to invest significant effort and have some technical proficiency to assemble the printer competently.
Difficulties with setting up
After full assembly, the electronics and power had to be set-up. This involved fine tuning the power to the motors, and double checking all connections. Installing the software was straightforward, with most drivers and settings available for download. The settings (e.g. clearance/access and speed), however, had to be fine-tuned for our specific assembly.
Alignment issues and auto calibration
The calibration of the printer was and remains a hit-or-miss scenario. The initial calibration involved some guessed measurements, as each system dimensions will be unique, since it was assembled ourselves.
Some gears and motors had to be refastened, in order to get smooth motion. The z-axis end-stop used for calibration had to be fastened and tightened a few times until the ideal setting was achieved. The layer height settings influence the starting layer and each subsequent layer. If incorrect, the nozzle might compress, or bump the object being printed, thus shifting its positions, ruining the print. Fortunately, these measurements can now be fine-tuned in software. (Studying the software user manual is just as important as the studying assembly manual)
The heat bed proved to be the most troublesome part. The object being printed has to stick to the bed in order to prevent it from moving around while being printed. If the bed settings are not ideal, the object might not stick correctly, and if the z-axis calibration is slightly off, any slight bump or pressure knocks the object around.
After a few tries, working settings could be achieved, allowing for printing to start.
View video of printing:
(https://www.youtube.com/watch?v=Wlxs5joeV3E&list=UULo67YCh8z836Mgl8-3-Zfw)
What would we do in future?
We would buy a ready to use, fully assembled 3D printer. We will also look for one where the base is stationary (unlike ours where the base moved and there were resultant problems), with the nozzle moving around; just to reduce vibrations and unnecessary movement on the object being printed.
And in the context of learning from 3-d printing this comment from Aldous Huxley is apt: Experience is not what happens to a (wo)man. It is what a (wo)man does with what happens to him.
Yours in engineering learning,
Steve
