Tips and tricks for printing with PETG filament?

[jeffmorris]

I think that I may have a bad spool of ESUN PETG white filament. Is the filament supposed to feel "rough" instead of smooth?

[ssayer]

Originally they made it smooth. They've long since changed it to the rough feel so that the gear grabs it better when it feeds it in.

[jeffmorris]

CIMG0103.jpg

Please check the objects and tell me what's wrong with them. I tried different extruder and platform temperatures. Any suggestions?

[ssayer]

Wow! Only guesses...

Extruder to hot.
Speed to fast.
Travel too fast.
Not enough retraction.
Need to add an active cooling fan (after the first layer).
Can't see the support very well (if any), but would guess need better support.
Probably all of the above...

[jeffmorris]

I cut the speed and travel in half. I reduced the extruder temp. I increased retraction. I added active cooling fan after first layer. I tried to use PVA as support material - terrible mess. What can I use for support material?

[Davo]

I print it with the exact same settings as ABS.

[ssayer]

I use PETG for support as I never use two print heads (well, I did a couple of times when I first started out because of the novelty, but...).

I can't compare the settings to ABS as I only used ABS a few times when I was starting out and just couldn't get past the smell.

[jeffmorris]

Should I use the same settings as ABS? What about the bed temperature?

[Alibert]

I print PETG at similar nozzle temperature as ABS (225 for PETG vs 230 for ABS in my printer), but at a bed temperature of 70C and at lower speed. PETG is more viscous than ABS, so you need to lower the printing speed to actually extrude as much plastic per unit of time as the slicers thinks it does. Increasing nozzle temperature to decrease viscosity leads to more stringing with PETG in my experience. Lowering printing speed works better.

[jeffmorris]

A few weeks ago, I found Simplify3D profile for PETG at http://forum.makergear.com/viewtopic...=2593&start=60 but I had to edit it for my printer. The prints looked better but they won't come off the BuildTak surface without using too much force and ruining the BuildTak surface and some prints. Yesterday, I found 3M 8952 tape and searched the Internet to see if I can use it for bed surface and found out from https://www.alibaba.com/promotion/pr...tion-list.html that I can use it for bed surface. I applied the tape to the bed, printed a manual transmission part using PETG and it came off the bed surface without any problems. I printed more parts and they came off the bed surface without any problems.