What calibration options should I look into given these defects

5

I printed a temperature calibration cuboid for Hatchbox 1.75 mm PLA, in 1 °C increments from 180 °C to 190 °C.

I have two questions related to this image:

Temperature calibration print

  • I'm not seeing any difference in quality across the temperature range. Am I just way off base and need to be substantially higher?
  • How do I get rid of the small layer shifts you can see across the board?

Printed on a RepRapGuru Prusa MK2 clone.

kolosy

Posted 2019-02-10T20:28:50.273

Reputation: 571

Most slicers/printers use Celsius and not Fahrenheit for temps. If you are running things in F (Fahrenheit), you're running your temps way too low. You should be running PLA around 200 °C. At 180 °F, this is ~82 °C ... I'm betting you mean you are extruding at 180 °C ... still, this is pretty low, even for PLA. I'd suggest running your temps from 195 °C to 210 °C and checking the difference. – Pᴀᴜʟsᴛᴇʀ2 – 2019-02-10T20:52:02.367

Woops. Yes, typo - C, not F. – kolosy – 2019-02-10T21:00:11.307

Even so, 180-190 is usually pretty low for print temps using PLA ... just a thought. – Pᴀᴜʟsᴛᴇʀ2 – 2019-02-10T21:07:49.853

Fair. I was under the impression that you want to go as low as you can without extrusion issues. Is that not the case? And will this address the unevenness I'm seeing? – kolosy – 2019-02-10T21:14:29.557

Couldn't what you are seeing be considered extrusion issues? Try it, as what do you have to lose but a little time and filament. – Pᴀᴜʟsᴛᴇʀ2 – 2019-02-10T21:19:08.497

Sure. I'm referring to what looks like unevenness or layers along the corners of the print. – kolosy – 2019-02-10T21:21:24.560

Answers

3

Your print does not suffer from layer shifts as you call them. This uneven layer deposition is typically caused by the (positioning) accuracy of your printer. All-in-all, this print does not look so bad. You would get better quality prints on a different style of a printer; most high-end printers have a lowering platform instead of a forth and back moving platform.

Although 180 °C is at the low side of printing PLA (usually it starts at about 185 °C), the print does look okay. However, looks can deceive, it does not say anything about structural integrity (layer bonding).

Note, to calibrate the temperature using a temperature tower, you need a different calibration test print, preferably one that tests overhang. This latter is usually far more important as there is normally not much to see at the walls, you need a slanting part in the print or an overhang to determine the optimal temperature.

0scar

Posted 2019-02-10T20:28:50.273

Reputation: 25 570