Sun, 12 Apr 2020

My first 3D printing mistakes and the lessons I learned

Konstantinos Stavropoulos

3dprinting

759 Words

Sun, 12 Apr 2020 16:06:13 +0000

I jumped on the speeding train that is the fight against COVID19. I encouraged everyone at work to stay at home, as I was the first one who took it seriously.

When I found out about the face shields that Prusa designed, I thought it was cool, but didn’t think Greece had a large enough community or the ruling party would reach out to someone. However, I was wrong. It was only the 6th of March until some people and a 3D printing Hub organized, started printing masks and contacted the government to get approval, the nation’s needs and show what Prusa has already achieved. The green light -I assume- was given immediately and so hundreds of amateurs and professionals joined the cause in less that a week!

I printed my first batch of 20 shields in a week, using much of my beloved Galaxy Silver Prusament. Then, since I could not get on the phone with a transportation company to ship them to the 3DHub, I decided to take them there myself and as I had a few more days to spare until I could leave the house, I printed another 10, for a total of 30.

I dropped them off and they guys there gave me two Prima Easyprint PLA spools, in order to print some more. At the time I thought it was a great move, and was excited to keep printing as soon as I got home.  

 

I did a quick maintenance on my MK3S, and put the new filament in. The first dozen of prints were great, and I played around with the slicer settings to get excellent prints. I gained some confidence and so I started printing the stacked versions. I got the first 4 stacks of two made, but on the next I noticed a lot of stringing and layer shifting… Trying to print as fast as possible, I slowed down the printing speed, and I had some good results again, but only for a couple of shields. Then, more stringing, worse than before…

I managed to get a single shield complete, despite all the strining, but I was very disappointed with the end product and started getting angry at the stupid filament. The first spool was done, and I had 21 shields, but I knew the quality of them was nothing near the first batch’s.  

 

Finally, the weekend came around and I started a tedious servicing of the printer, which I had scheduled for the Easter holidays. I dismantled the extruder and found that the bondtech gears were full of little bits of Prima PLA, strings and PLA dust was everywhere, and the nozzle was half clogged. I was so angry! So, much for volunteering and contributing! I could have done damage to the machine with this stupid PLA!

I cleaned the nozzle by heating it up with a lighter and brushing it with wire. I removed all the junk that was clogged inside (all the material I found was just from this Prima PLA). I cleaned the extruder endpoint, by heating it up to 270 degrees and picking off all the little bits. I dusted off everything, lubed all the rods, slightly greased what was needed, and put everything back together.

Did a calibration, printed some tests and… I had leakage! leakage from the connection of the extruder with the nozzle. I thought I was so smart with leaving the exact distance between them that is recommended! So, I tightened the nozzle, and did some more tests. Everything looked great, so I decided to give the same filament another chance. Ha! Fooled again. A shitshow of a shield started printing, even though my benchy and batarang, and calibration prints were totally fine.  

 

I threw the Prima PLA back in its box, cleaned everything once again(there goes the evening…) and put in my favourite Galaxy Silver Prusament. I have 22 shields now, I also gave 2 to a friend who is a dentist, and I will keep printing to reach 30 and then send them in.  

 

Lessons learned:

  1. Service the printer regularly and thoroughly.

  2. Make calibration checks every time you change something.

  3. Level the bed as much as possible (Octoprint helped with this)

  4. NEVER PRINT WITH LOW QUALITY FILAMENT.  

 

Agreed, I made some foolish mistakes, and some foolish choices, but I risked doing damage to the printer, and for that I mostly blame the filament. My production has slowed down, but the road to 60 shields is ending, and I will consider printing more with Prusament and not any other filament.