Simplify3D User Forum

Hi

PETG is my new go too filament, It's like the perfect mix of ABS and PLA:)

It does have one down side tho, It's stringy when printing which makes bridges especially tricky. Now Simplify 3d has awesome cooling setting for bridging already, but my problem occurs more when bridging over infill. Turning on the cooling fan helps a lot. But cooling significantly decreases layer adhesion if I set the cooling fan for the entire print.

So yeah a cooling overide option for bridges(including over infill) would be GREAT!

Interesting dilemma... there are a lot of settings on the cooling tab. Have you tried the "Bridging fan speed override"? There's also bridging controls in the "Others" tab. A combination of these settings can help control the cooling for the single (first top layer). The cooling should return to the normal settings after the bridging layer.


You could also try denser infill to support the top layer... or more top layers. Even if the lower most layer sags, the print usually recovers by the next layer. But I understand if its not feasible aesthetically in some situations... and PETG is a particularly runny material to print with (lowering the extrusion temp, could help also).

To vary the infill density, add a second process with a denser infill to finish off the object.
Good write up about adding processes to vary density of the object:
https://www.simplify3d.com/support/tuto ... f-a-model/

Video about adding processes:
https://www.youtube.com/watch?v=EbQfifnzL4Q

Hope that helps.

Jadonm1 wrote:Hi

PETG is my new go too filament, It's like the perfect mix of ABS and PLA:)

It does have one down side tho, It's stringy when printing which makes bridges especially tricky. Now Simplify 3d has awesome cooling setting for bridging already, but my problem occurs more when bridging over infill. Turning on the cooling fan helps a lot. But cooling significantly decreases layer adhesion if I set the cooling fan for the entire print.

So yeah a cooling override option for bridges(including over infill) would be GREAT!

I use PETG mostly too, I've just had to start using a more dense infill and modify a few other things to assist with top fill and stringing. So far my most successful settings have been at max for the filament, sometimes higher, using a very small negative restart distance, about a .1-.15 vertical lift, and 2+ on retraction. It's weird but overheating slightly, not enough to cause bubbles, has a tendency to lower stringing while increasing layer adhesion. with the increased I can set my one 40mm fan to about 20% starting on the second layer.