Head leave lines on part - Extraction

Ok, must admit, I am a little frustrated. I am trying to print a fairly simply part that is essentially flat using ABS. As the head extrudes, all well and good. But when it then moves across to another place to start extruding it leaves a slight mark on the part where it has traversed across.

I have tried reading up on it on the net and have attempted to play around with the Extraction settings? I have to admit changing the settings on that doesn’t appear to have made any difference at all. If I watch the print head when it moves I don’t see the extruder go reverse at all, is that not what extraction does or am i missing something.

I have a Taz 5 and I am using Cura.

Any help or assistance would be greatly appreciated, i feel like I have got up and running fairly quickly but trying to perfect the results is giving me headaches!

Retraction does indeed pull the fillament back, often on moves. Even with that though, it’s not unusual for nozzle drag to leave a light mark across a layer surface when it moves. That can sometimes also indicate slight overextrusion, or a nozzle that doesn’t maintain an air seal in the melt chamber, but even the best printers do that on occasion. You can avoid it by telling the printer software to avoid crossing perimiters, or even “lift on movement” in some slicer programs, though the latter causes more issues than it fixes usually.

I use Lift on Retraction fairly often if I want a smooth surface. But internally you will not see the nozzle drag marks due to the filament expansion. Just remember that retraction is like using a straw and tends to suck any small features back away. I pointed that out to a person a couple weeks ago that was trying to figure out why his small crown-like feature on the top of his part was not getting printed correctly. :laughing:

I use lift retraction for a print with delicate pillars… marks across a large surface sounds like over-extrusion. Try dialing back the flow rate by 3-5%. If that helps, you can leave it or it could be a sign your e-steps are off.

Check the calibration of the extruder… mark the filament 120mm from the top. Extrude 100mm, measure the mark. It should be 20mm from the top. If not follow the calibration steps in this guide.

Thanks for your help all, good info and things to try there :slight_smile: