Trying to print PETG - Any Idea what causes this?  

RE: Trying to print PETG - Any Idea what causes this?

Sure wish I could edit posts. Just a quick note to point out that the previous PETG results were with 3 perimeters using Slic3rPE beta (now PrusaSlicer).

RE: Trying to print PETG - Any Idea what causes this?

Ah yeah. Cura. Detect thin walls doesn't do the same thing in Cura as it does in Slic3r (or PrusaSlicer).

RE: Trying to print PETG - Any Idea what causes this?

Thanks very much for all the tips.  The brim - well that's there due to my ignorance and nothing else - haha.  I'll turn it off for future items.  As for the beds being clean.....well, this is in a room with about 30 3d printers and a constant stream of about 1000 engineering students printing items from a duration of 1 hour to 1 week, so you can imagine the state of affairs at times.  However, it's summer time now here and there's very few students around.  I've swapped out several buildplates and am using a fairly clean one.  We also did a Z calibration on the latest one.

I will look to post my .3mf and .stl files up on m dropbox account and post the link here shortly. 

Cheers,

Lewis

RE: Trying to print PETG - Any Idea what causes this?

ok - here's the .3mf and .stl files on m dropbox account.  One thing I should mention if I didn't before- the infill is set at a rather obscene 80% in this - but I'm only changing things one at a time to try and isolate the issue so I have been leaving at this value for now.

https://www.dropbox.com/s/qhyl9zg53oosg3o/PETG%20Test.stl?dl=0

https://www.dropbox.com/s/5af40ftz0iu26q5/PETG%20Test.3mf?dl=0

Cheers,

Lewis

RE: Trying to print PETG - Any Idea what causes this?

Posted by: lewishcobb

ok - here's the .3mf and .stl files on m dropbox account. 

I did a quick print using PrusaSlicer with my PETG profile at 0.20mm layer height with a 0.40mm nozzle. Here's the 1st layer:

I tweaked the Live-Z upwards (less negative by 0.3mm) after the top-left printed. You can see the 1st layer went down smoothly. Here's the top after printing:

The top layer isn't perfect, but most of the extrusions close up nicely, except the bit at the top of the center and left of the center spokes. I'd work on extrusion widths and overall finish for a final print, but this shows PETG can go down cleanly with few gaps.

One thing I should mention if I didn't before- the infill is set at a rather obscene 80% in this - but I'm only changing things one at a time to try and isolate the issue so I have been leaving at this value for now.

This part is so thin that there's really no room for infill. I'd tune it back for most parts as the extra perimeters make more of a difference for part strength.

I've copied the configuration used to print this here if you want to give it a try in PrusaSlicer.

RE: Trying to print PETG - Any Idea what causes this?

Bobstro -

Thanks a million for the help with this.  I've downloaded your PrusaSlicer settings for reference .  Your prints look perfect as far as I am concerned.  I'll get back into the university next week and tweak some of the settings along the lines that you've suggested.  There's a lot to learn with these 3d printers I'm discovering, but that's the fun of it.  For a retired guy it sure beats hanging out at the coffee shops !  I'll report back when I re-run a few more tests.

Cheers,
Lewis

RE: Trying to print PETG - Any Idea what causes this?

Hi - I have not been able to get back into the university to run the next set of tests yet, but will post as soon as I do !

Lewis