First time printing with petg, problems.  

Re: First time printing with petg, problems.

your a god send I used these settings and my Petg problems went away did a test on a batman logo using prusa slic3r and did an amazing job. I'm starting the pi easy access case for the einsy and 2 hours in still doing well. thank you the ambient temp in the room is 24'C I also found that by slowing the speed on the knob to 85-50 the gaps near the outline edge of the lair closes up a bit more

Glad to hear that the settings helped. Maybe you could also try increasing the extrusion factor in tiny steps like 0.01 to see if that improves the gaps. When I experimented with very low extrusion factors like 0.8, I noticed lots of gaps near the outline, so that may have an effect in addition to the speed. On the other hand, if filament starts to build up on the nozzle, then the extrusion factor is too high (in my limited understanding).

Re: First time printing with petg, problems.

your a god send I used these settings and my Petg problems went away did a test on a batman logo using prusa slic3r and did an amazing job. I'm starting the pi easy access case for the einsy and 2 hours in still doing well. thank you the ambient temp in the room is 24'C I also found that by slowing the speed on the knob to 85-50 the gaps near the outline edge of the lair closes up a bit more

Glad to hear that the settings helped. Maybe you could also try increasing the extrusion factor in tiny steps like 0.01 to see if that improves the gaps. When I experimented with very low extrusion factors like 0.8, I noticed lots of gaps near the outline, so that may have an effect in addition to the speed. On the other hand, if filament starts to build up on the nozzle, then the extrusion factor is too high (in my limited understanding).

will try that on my next print. Thanks again for the info.

Re: First time printing with petg, problems.

Just FYI - I spent lot of time experimenting around with PETG on MK3. 3DBenchy was OK, but thin wing parts for an RC plane were horrible - stringing (not surprising), but also missing/damaged edges of thin parts. Tried to change many parameters, performed mechanical checks. Nothing helped.

Result:
- Reduce printing speed for thin parts - 30-50% is perfect, 70% still acceptable
- Fan 100% all the time
- Higher layers - 20

Reduced speed mean of course longer print time for such parts. I was not able to find another better solution. And again - 3DBenchy is OK even with 100% speed.

GL&HF,
Radek

Re: First time printing with petg, problems.

After having real problems with Prusa PETG during my first row of prints, I've finally managed to tune this in Slic3r so that print quality and performance matches Prusa PLA on my printer, which by my definition means virtually string-free, smooth finish prints which stick to the bed.

Here's what works for me when printing with layer height 0.2mm.

General Notes:

Filament settings:

Print Settings (Layers and Perimeters):

Print Settings (Skirt and Brim):

Print Settings:

Printer Settings:

This is an older post, but I just want to say thank you, because your settings really helped me out with printing PETG for the first time. I was having similar first layer issues to the OP on this thread, and those issues are almost 100% gone with just the settings provided above. I'm fine tuning now to get rid of the last bit of stringing on the part and there are a few tiny gaps at the border, but the parts are turning out great now. Thank you!

Re: First time printing with petg, problems.

This is an older post, but I just want to say thank you, because your settings really helped me out with printing PETG for the first time. I was having similar first layer issues to the OP on this thread, and those issues are almost 100% gone with just the settings provided above. I'm fine tuning now to get rid of the last bit of stringing on the part and there are a few tiny gaps at the border, but the parts are turning out great now. Thank you!

You're welcome. I'd like to add one more observation of mine which might be useful for others in the same situation too:

I recently made prints with a half full spool of PETG which had been opened like a couple of weeks ago. Now, my listed settings suddenly did not work at all anymore and resulted in inconsistent under-extrusion, like thin strands of filament with little blobs inbetween. Common wisdom as far as I've researched would suggest a moisture problem and the need to dry and desiccate the filament in the oven or by similar means for hours. But, being an impatient guy, I didn't have time for that. So I started to increase the extrusion multiplier in the hope that this would force the filament out no matter what. And indeed, I got the same OK results with a multiplier of 1.05 which I would normally get with a "healthy" spool and a value of 0.85. So now I created two profiles with different multipliers, one for "fresh PETG" and the other one for "aged PETG". Your mileage may vary but my point is that the right extrusion multiplier really seems to be a critical factor with PETG.

Re: First time printing with petg, problems.

You're welcome. I'd like to add one more observation of mine which might be useful for others in the same situation too:

I recently made prints with a half full spool of PETG which had been opened like a couple of weeks ago. Now, my listed settings suddenly did not work at all anymore and resulted in inconsistent under-extrusion, like thin strands of filament with little blobs inbetween. Common wisdom as far as I've researched would suggest a moisture problem and the need to dry and desiccate the filament in the oven or by similar means for hours. But, being an impatient guy, I didn't have time for that. So I started to increase the extrusion multiplier in the hope that this would force the filament out no matter what. And indeed, I got the same OK results with a multiplier of 1.05 which I would normally get with a "healthy" spool and a value of 0.85. So now I created two profiles with different multipliers, one for "fresh PETG" and the other one for "aged PETG". Your mileage may vary but my point is that the right extrusion multiplier really seems to be a critical factor with PETG.

Good to know. I'll keep that in mind if/when I start having issues. For now I'm still on my first spool of PETG, which was opened less than a week ago so it seems to be doing well.

Re: First time printing with petg, problems.

Thanks for this. I'm about 1/2 way through my first PETG print and it looks awesome so far. Just the tiniest bit of stringing.

Re: First time printing with petg, problems.

Turns out I'm not quite there yet.

I printed some small parts (the door handles) for the Lack enclosure with the settings in this post and they came out reasonably well. There was minimal stringing and a teensy hole next to the perimeter in one corner.

I then started to print some of the larger parts. The first problem is that I get a tiny bead at the start of the perimeter on the first layer. When it's printing the solid fill for that layer, the nozzle grabs the bead, drags it across the layer and I'm toast.

I've read a lot about blobs (particularly https://www.simplify3d.com/support/print-quality-troubleshooting/ & https://www.simplify3d.com/preventing-blobs-on-3d-print/ )... my extruder multiplier is set to .85 and the first print was pretty decent so I don't think I have too much plastic. The bit about coasting sounds interesting, but I read another post that suggested it's a bit of a hack.

FWIW, I cloned the printer settings for "Original Prusa i3 MK3", then modified the settings as specified in this thread. So Lift Z is still set to 0.6mm, above Z to 0 and below Z to 209mm. Retraction speed is 35mm/s, extra length on restart is 0mm and minimum travel after restart is 1mm.

After reading those articles, my gut says I need to tweak the extra length on restart... but I haven't yet wrapped my head around all the options and their effects on the print.

Could use some suggestions if anyone has one.

Re: First time printing with petg, problems.

Turns out I'm not quite there yet.

I set the extra length on restart to -.02mm. The near-perfect first layer printed first on the right side of the bed. The other one started to print next on the left side.

Calibration issue? Leveling issue? Something else?

Re: First time printing with petg, problems.

It's something else. I had the same problem when I switched from a regular brass nozzle and aluminium heater block with a professional sock too a plated copper nozzle and plated copper heater block without sock. Even putting a sock back on did not solve it fully. The solution was a ridiculously slow first layer speed of 7mm/s.

Regards,
Martin

Re: First time printing with petg, problems.

I set the extra length on restart to -.02mm. The near-perfect first layer printed first on the right side of the bed. The other one started to print next on the left side.

Calibration issue? Leveling issue? Something else?

The upper model looks to me as if the nozzle tore off part of the already laid down filament when passing over it later (but you as an eye witness will know best what happened). This would be typical for a Live-Z height issue (nozzle too low = catches on filament). But since your other sample was much better, I'd suspect leveling issues and do a full recalibration plus more tests on different sides of the bed. If the differences between the results from either side are not consistent and repeatable, I'd also consider surface contamination and do a thorough cleaning with acetone followed by Windex.

Re: First time printing with petg, problems.

The upper model looks to me as if the nozzle tore off part of the already laid down filament when passing over it later (but you as an eye witness will know best what happened). This would be typical for a Live-Z height issue (nozzle too low = catches on filament). But since your other sample was much better, I'd suspect leveling issues and do a full recalibration plus more tests on different sides of the bed. If the differences between the results from either side are not consistent and repeatable, I'd also consider surface contamination and do a thorough cleaning with acetone followed by Windex.

We came to the same conclusion. I redid both XYZ and first layer calibration followed by the procedure from https://shop.prusa3d.com/forum/assembly-and-first-prints-troubleshooting-f62/life-adjust-z-my-way-t2981.html#p90991 but I'm not nearly as happy with my first layer as I was before. I had one bear of a time getting a solid print.

Where I am right now is that one side of the "live z" rectangle is spectacular and the other side is a bit lacking. It's as if the top-right of the bed is flawless and the bottom-left is still out of whack, but I don't yet have octoprint so I can't do deeper analysis of what's happening.

Re: First time printing with petg, problems.

It's something else. I had the same problem when I switched from a regular brass nozzle and aluminium heater block with a professional sock too a plated copper nozzle and plated copper heater block without sock. Even putting a sock back on did not solve it fully. The solution was a ridiculously slow first layer speed of 7mm/s.

Just a small update. I have retuned my PETG settings for the platted copper nozzle and block combination without sock.

I increased my Z offset from 0.2mmm to 0.3mm this completely eliminated any dragging. So I upped my first layer speed to 30mm/s (the default in Slic3r as set by Prusa.) A perfect first layer at speed.

Regards,
Martin

Re: First time printing with petg, problems.

The upper model looks to me as if the nozzle tore off part of the already laid down filament when passing over it later (but you as an eye witness will know best what happened). This would be typical for a Live-Z height issue (nozzle too low = catches on filament). But since your other sample was much better, I'd suspect leveling issues and do a full recalibration plus more tests on different sides of the bed. If the differences between the results from either side are not consistent and repeatable, I'd also consider surface contamination and do a thorough cleaning with acetone followed by Windex.

Turns out my issue was completely self-induced. I first had trouble with some globs and decided to clean my nozzle before continuing. Being here in the U.S., I am so not used to Celsius temps... and being a newbie, I used a .4mm bit not knowing the nozzle was a lot hotter than I thought it was. So I think what happened is I literally melted the end of my bit and when the nozzle fully cooled, it sucked molten metal up into the nozzle. I didn't realize the error of my ways until I happened to notice that my other unused .4mm bit was a lot longer than the one I used. I replaced the nozzle and inspected the old one. I can't even get the .4mm bit to go in all the way.

So lesson learned. I haven't had time to do any more printing... but I'm pretty sure the decreased extrusion rate caused me to set my live z way off and everything went south from there.