small cylinders problems

[FAB1150 0]

hi, i recently got an anet a8 to play with.

i was surprises of how well it printed, until i tried to print a small object. 

i'm new to 3d printing but it seems like it underextrudes quite a bit when doing small tubes or holes, creating some strange patterns and lowering significantly the structural integrity of the print.

When doing normal sized things it does a perfect job almost all the times, but this thing happens also sometimes in big objects (apparently at random times, but it isn't random as it never fails if it failed before and it fails again if it failed before)

i'm using CURA 3.1.0, what setting did i get wrong? i am not findind it!

[gr5 2,189]

What is your layer height here?  Maybe try a bit thicker layers?  Is the fan working?  I'm not convinced it's underextrusion.  maybe retraction settings or hardware issues.  Maybe your layer height is simply too thin.

[FAB1150 0]

4 hours ago, gr5 said:

What is your layer height here?  Maybe try a bit thicker layers?  Is the fan working?  I'm not convinced it's underextrusion.  maybe retraction settings or hardware issues.  Maybe your layer height is simply too thin.

i'm using 0.2 mm layer height, the fan is working fine.

it could be the retraction as this thing happens where the layer starts. maybe it tries to start the layer before it starts to extrude? how could i resolve this?

[gr5 2,189]

I'd look over all the retraction settings - I don't know the A8 but if the feeder is on the print head retraction should be no more than about 1mm and if the feeder is far away from the hot end and you have filament going through a bowden that connects the feeder to the hot end then retraction should be closer to 4mm.

 

I mean the problem really seems to start suddenly when the retractions start.

 

Also look at the part in layer view and I think cura has a way to show normal non-printing moves (blue lines) differently than retraction moves (lighter blue lines).  Make sure to check the checkbox for showing "travels" when in layer view.  You want only light blue (retraction) moves from one finger to the next.  Darker blue would be expected within a given finger.

[FAB1150 0]

38 minutes ago, gr5 said:

I'd look over all the retraction settings - I don't know the A8 but if the feeder is on the print head retraction should be no more than about 1mm and if the feeder is far away from the hot end and you have filament going through a bowden that connects the feeder to the hot end then retraction should be closer to 4mm.

 

I mean the problem really seems to start suddenly when the retractions start.

 

Also look at the part in layer view and I think cura has a way to show normal non-printing moves (blue lines) differently than retraction moves (lighter blue lines).  Make sure to check the checkbox for showing "travels" when in layer view.  You want only light blue (retraction) moves from one finger to the next.  Darker blue would be expected within a given finger.

i had the retraction set to 2.6mm, i set it to 1, i'll try to print with that, thanks

[FAB1150 0]

i'm a bit late now, but that wasn't the problem. i'm still having the same issues :/