PETG Layer Adhesion

The place to discuss filament...
Post Reply
User avatar
JohnnyRobot
Posts: 128
Joined: Tue Apr 22, 2014 9:25 pm

PETG Layer Adhesion

Post by JohnnyRobot » Tue Mar 17, 2015 4:44 am

So, I've been working more and more with PETG. I like it a lot, but I've discovered that my layer adhesion isn't that great.

I can tear my parts apart, strand by strand, layer by layer. I have a V3B hot end and I'm printing at 250° (Afraid to go higher) 40mm/sec

Any ideas?
╒═════════════════════════════════════════════════════════╕
-- Hi! No signature here.
╘═════════════════════════════════════════════════════════╛

jsc
Posts: 1864
Joined: Thu Apr 10, 2014 4:00 am

Re: PETG Layer Adhesion

Post by jsc » Tue Mar 17, 2015 4:56 am

You will have to provide more details on your print settings for any chance of useful help. Zip up your profile and upload it.

User avatar
jimc
Posts: 2888
Joined: Wed Apr 09, 2014 11:30 pm
Location: mullica, nj
Contact:

Re: PETG Layer Adhesion

Post by jimc » Tue Mar 17, 2015 12:28 pm

Yeah something isnt right there. Of all the plastics petg layer bonds like crazy. Are you using petg or pet+? Opaque pet+ will do what you describe.

Bratag
Posts: 438
Joined: Wed Jan 14, 2015 5:33 am

Re: PETG Layer Adhesion

Post by Bratag » Wed Mar 18, 2015 9:50 pm

Had this problem until I started running with the fan off through the entire print. Additionally you really need to make sure you have your extrusion multiplier set correctly.

User avatar
JohnnyRobot
Posts: 128
Joined: Tue Apr 22, 2014 9:25 pm

Re: PETG Layer Adhesion

Post by JohnnyRobot » Fri Mar 20, 2015 7:35 pm

Here's my zipped factory file. Sorry it's taken me so long, I've been out of town.

Using PetG blue. No cooling fan. Extrusion Multiplier at 90. Maybe the adjust print speeds for layers <15sec? It's a small part.

If you guys see anything, please let me know!

Thanks.
Attachments
Closet-Sliding-Door.zip
(47.21 KiB) Downloaded 584 times
╒═════════════════════════════════════════════════════════╕
-- Hi! No signature here.
╘═════════════════════════════════════════════════════════╛

jsc
Posts: 1864
Joined: Thu Apr 10, 2014 4:00 am

Re: PETG Layer Adhesion

Post by jsc » Fri Mar 20, 2015 8:26 pm

Just a few quick notes, not anything that will definitively solve your problem, but things I noticed:

You have M108 S155 in your start up gcode. On a recent vintage M2, that will turn OFF your extruder fan or cause it to run at approximately half speed. Remove that line, or change it to S255.

Your infill extrusion width should be set to 150 or 200 for PETG.

Is .90 extrusion multiplier accurate? Run an extruder multiplier calibration, there's a thread in the tips forum. I find 1.0 is closer for me, and I see numbers of > 1.0 in other people's calibrated profiles. Also measure and input your correct filament diameter if it's not exactly 1.75mm.

Ed just today has posted details of his PETG profile, you may want to try to glean some wisdom from it: http://softsolder.com/2015/03/20/makerg ... -for-petg/ He is using Slic3r, but many of his recommendations will carry over. Note that he does a 3 layer combined infill, which has the effect of a 300% infill width, albeit printed 3 layers apart.

Post Reply