Print Quality After Layer >~6

I’m a new owner of a Taz 5, 0.35mm extruder. Here’s a photo of a print I’m having random success with. Material is PLA. Slicing with Simplify3D, Medium, 3mm filament set to 2.9mm based on averaged caliper measurement. Rectilinear infill both internal and external. Lots of settings… don’t know where to focus my testing.

Thanks for your ideas!

To isolate whether it’s a printer issue or a setting in simplify, try installing CURA and printing the rocktopus. If it succeeds, you know to fiddle with simplify. If it fails, you know to look at the printer.

Good advice. Thank you.

Here’s the default print from Cura:


I changed to “Advanced” settings and found three discrepancies.

• default nozzle size was 0.40, changed to 0.35
• shell thickness was not a multiple of the extruder width, changed to 0.7 (from 0.8)
• initial layer thickness was > 3/4 of nozzle size, adjusted to .26 (from .30)

Here’s the better version, but still faulty:


The shiny bubbles on the raised tentacle could be from clogging/spurting. I’m not sure how to fix.

The filament strings/hairs could be from retraction settings. I’m not sure how to fix.

Any help appreciated!

What temperature are you printing at? Looks like part of the reason could be temperature.

extruder @ 205
bed @ 60

I just imported the “0.35 mm Nozzle Fast, 0.28 mm layers” Cura profile and printed the rocktopus and still having some kind of Z issues.

Hmmm…

When you switch to full settings, be sure to load in a filament specific profile. Older versions of Cura will revert to very generic settings that do not work well with our printer. (Hence the 0.4mm nozzle.) Try the print in quick print mode, and see how it comes out.

If you would like, download our latest version of Cura here: lulzbot.com/cura We have 20 different types of filament profiles pre loaded in. Also, when you switch to full settings it will give you the option to automatically port over the profile, so you can make individual adjustments.

I hope this helps!

I installed the new 0.5mm hot end and printed using the Lulz Cura. I’m still having the same problem after 2-5 layers. It almost seems like the Z-axis isn’t moving high enough to accommodate the next layer. The nozzle rubs on the previous layer(s) and starts smearing. On my small PI print (above) it happened at the very top layer (shell?). On Rocktopous it happened right away on layer 3 around 2mm high. However, it’s not precisely repeatable… I’m trying to minimize variables between prints, but the Rocktopus takes 37 minutes to print vs. the PI symbol’s 5 minute prints. Quicker iterations on the PI.

Anyways, on the latest Rocktopus it seems like the nozzle was rubbing into the previous layer. Settings were: Standard speed. Layer height .25mm, 1mm bottom/top thickness, 50 mm/s print speed. Printing temp/bed temp are 0, so that must inherit from the printer, which is 205C and 60C. The PLA I’m using is Velleman from MicroCenter. Label says 190C-225C print temps.

Any ideas?

The initial layers were nice, I think. Good adhesion.

Layer 1


Layer 2

Layer 3/4
layer 3.png

That looks very shiny for PLA. I don’t have any experience with Vellemen, but printing VP PLA hotter will produce shiny results. Have you dropped temp down to say 190c and see how it goes?

I tried a few more prints using an initial layer thickness that was a multiple of the layer height, as well as tightening the filament tensioner on the extruder assembly. No difference. It really does seem like the layer height isn’t moving in the correct amount. I remember reading a post about how the numbers are converted to motor steps… could mine be off?

Xsteps/mm 100.5
Ysteps/mm 100.5
Zsteps/mm 1600
vZ-jerk .4
vMax Z 3

Thoughts?

Looking again, that octo does look a little short. Have you checked the controller box fan?

We had one report awhile back that had his come loose in shipping: https://forum.lulzbot.com/t/new-user-calibration-cube-issues/1521/7

Correct. My fan is broken. It desperately wanted to spin but one blade was cracked. I’ll replace and report back.

It seems we need some kind of thermistor to detect overheat events in the control box.

I’m excited that this might be the fix.

I am sorry to hear about the fan! Please contact our support team at support@lulzbot.com or at 1-970-377-1111 to let them know. If you are still within your warranty period, they will be more than happy to get you taken care of. If you are not within that period, they will be able to point you toward the replacements required.