Problem: Small filament balls on top of first layer with primaSELECT PETG

[sn4k3]

Hello,

I’m having very bad time tryng to print PETG, primaSELECT PETG Solid Silver.
I have tried thier temperatures, among with lower settings, prusa settings, increase extruding rate to 1.11 based on my calcs, change retraction but nothing helped, problems at any settings i try!
Print well with Prusa PETG and Moebyus PETG without any problem but this primaselect is a pain.
Also create a lot of strings.
I’m using latest Slic3r Prusa Edition with MK2S stock

Anyone know the cause or had this filament brand?

First Layer:

[img]http://i.imgur.com/GwmHLlo.jpg\[/img\]
[img]http://i.imgur.com/Tf4y1zC.jpg\[/img\]
[img]http://i.imgur.com/BKXDDTG.jpg\[/img\]

[wirlybird]

First layer looks to close or thin. Raise your Live z. PETG does not like being squished. Also print slow.

Measure your filament and enter the value in the slicer. One PETG I use is consistently 1.7 instead of 1.75. this can make a difference.

If you are getting accumulations on the nozzle then you will need to reduce the extrusion multiplier not raise it but only by small increments.

[sn4k3]

Thank you, i raise to 0.300 instead of 0.200 and solved my problem.

Still model come with imperfections

Bottom layer come all good, no imperfection
With this setting i got a bit less of strings, still not that less.
Also surface is not clean as other filaments, a tiny dot of filament is left on top layer but that can be easly cleaned, no more than 20 dots.
And last it left some scars on model

Seens this PETG melt at lower temps, i’m using the max recommened 230-235 but it works at 190. Can this be a problem in terms of resistance?

Bottom Layer: http://i.imgur.com/OcDDaTs.jpg

Scars: http://i.imgur.com/5AqebUF.jpg

Scraths: http://i.imgur.com/rPrzVf3.jpg

Strings: http://i.imgur.com/N1EIMu7.jpg

I print this without setting overextrude overall, my calcs give 1.11% rate but i print a test model and come worse than 1%. Also in octoprint i use to extrude 100mm at 111 rate and it stop exactly at same position if i use prusa lcd controls to extrude 100mm. Can’t understand this, if flow rate is 0.11% more why it stops exactly at same height?

[wirlybird]

Most PETG that I have seen has a temp range of 230-250. If this extrudes at 190 I would be somewhat suspicious of it. That is really low.

In general PETG is probably going to want a slight under extrusion.
As far as extrusion I would use the Prusa default and only adjust a little from there. You will want to calibrate the extruder at some point. You will need to go to the Prusa forum or google on how to do it for that machine.

You can work with the retraction settings for the stringing. Some filament brands are worse than others.

Print speed will also play a factor. Overall I used the default PET settings in Slic3r PE for PETG then adjust a little to fine tune and it has worked good.

[wirlybird]

I do not use Octoprint but if you are just telling it to extrude X amount then that is all it is doing so whether it is from the control panel or Octoprint it is the same.

I think the flow rate doesn’t matter there. You are just telling it to move 100mm of filament or what it thinks is 100mm.

[sn4k3]

I used this to calculate the flow rate: http://www.urbanexile.net/2016/12/3-tips-for-the-prusa-i3-mk2/

Tip 3, but in end 1 works better than 1.11

[sn4k3]

On box they say:

Print temp: 195-235ºc

Bed temp: 35-60ºc (On website they say heatbed no required)

I have to say that i test low temp, like 200 and 210, but it comes a little weak and tends to not stick well.

Prusa PET profile works well for this, i have cloned the profile and change temperature to 230-235 and bed to 50-55. Since this print with lower bed temperature is good, bed take a lot of time to heat up at high temperatures and also spare electricity

About retraction i tried many different settings and run a test model that i found on thingverse, didn’t help.

But i will keep testing, it must have an optimal setting

Can this be any kind of easy to print PETG?

I just buy this because its accessible in europe, i can’t find eSun PETG inside europe.

[wirlybird]

Bottom line is that not all filament is created equal.

I pretty much run at default retraction. It may just be the way this particular filament or color is being more stringy.

I have a purple PLA that is very stringy and the red in the same brand doesn’t string at all.

Google about printing PETG. Lots of info. It’s fussy stuff but once you get it dialed in it is very good.

[sn4k3]

After print a Marvin at 0.100um the results are quite positive.

Just small imperfections at left ear and bottom bridge. No Post-Process

[sn4k3]

I have posted a review of this filament here: primaSELECT PETG Temp Calibration Tower by sn4k3 - Thingiverse

If anyone interested or pretend to use it.

[pumpal]

Bad experience too here with PrimaSelect PETG, even exactly the same color … Looks best at 220-225C (fan Off), retract 1.2@20 gives almost no stringing, but the resulting things even not looking that bad are super fragile - no, they do not delaminate, they broke with bare hands …

[sn4k3]

My problem was calibration, since my bed are distorced, i have to modify firmware to support 9 point manual calibration, it solve my problem. I found this filament to be strong, do you use a heatbed? Please see my review on thing verse, you have a temp tower

[pumpal]

Hi, I read your review in Thingyverse - thanks for sharing! Yes I use a heatbed, initial layer 80C, after that 60C. I print initial layer @230, 220C the rest… … My bed is also not level perfectly most of the time , but the printer does not support auto leveling of any kind … still, I have no problems with warping or anything, the parts does not look bad as well, are just not very strong … Will try some other PETG now and compare … this Prima was my first PETG attempt …

[pumpal]

That’s what happens - some early try: https://goo.gl/photos/6ZYWPUGGYprUMZMNA … then I got settings better, things look prettier and printed some boxes (I need to use that material for something at the end… ) they are not very strong and one broke very easy on me … same printed in PLA is much stronger … Printer is a Wanhao i3 v2.1 with Flexion HT…

[sn4k3]

Looking at model structure it must be strong… Not sure why this happen to you. I’m using 1.75mm filament Prusa MK2S but your problem is the print streng so it can’t be related to advanced settings. Print temperature and bed directly influence that aspect, i can share my profile if you want: https://pastebin.com/xDj8LDQD Also you can try same temps as me. There are no reviews on internet to know if prima suffer from spool differences

[sn4k3]

Thats strange, my is quite strong, what model are you printing and how much of infill? But yes this PETG looks suspect compared to others PETG, i use also Prusa and Moebyus PETG and they always come good at first try without tweak, with stock settings

[pumpal]

Thanks - appreciated! Will give it a try next time I feel like giving it another chance …

[sn4k3]

Yes you shound’t quit, keep trying, it must work somehow