So I might have a very very slight under-extrusion here, maybe just 2%, but the external perimeter walls are well bonded together with absolutely no gaps, infill is almost there, but the walls on the round hole are way too under-extruded in comparison to the rest of the part. If I increase extrusion just a bit, I will get good bonding between walls in the inner hole, but it will be too much for the rest.
Using Simplify3D, so there is only one setting for external perimeter, no matter if it’s on the outside of the part or an inside hole.
Any thoughts ?
I would try calibrating the extruder, it may also be slipping a bit on higher speed moves.
Hi @Romeo_Pavel what’s your Outline Overlap set to? I’d still say an increase in extrusion will help, without causing problems; that surface is showing some signs of underextrusion…
@Jon_Gritton Outline Overlap was set to 14%.
The thing is, I’ve been trying to adjust extrusion, but it seems that I don’t manage to get the right extrusion when it comes to inner circles like this. I will try to print a few samples with different extrusion settings to see what’s the best of all…
you are perfectly fine. Don’t overextrude like all others do. The inner circle looks like (but it isn’t) underextrusion, because the just laid down track wants to “shorten” and therefor pulls itself towards the middle. You are printing inner perimeter first, right? Thats why the outer circle-perimeter looks perfect, they shorten, too, but against each other not away. Look this perfect extrusion of an 0.2mm nozzle of mine, there are gaps, too.
@Rene_Jurack I am printing external perimeter first for accuracy. The small gaps between walls and infill doesn’t bother me, but the gaps between the walls on the inner hole.
As per @Rene_Jurack , I believe that those gaps are not extending up the part, they just appear on the first layer, or maybe a few layers, until the pulling of the other layers stabilizes and so the problem doesn’t happen but at the lower periphery of the part.
@Romeo_Pavel That is the top surface of your part correct? If so it does look like you have slight under extrusion. Try increasing the temperature by 5C. When I know I’m not under extruding but I’m still getting a gap like that on shells a small temperature bump often solves the problem.
If that is the bottom surface then I would increase the flow a little for the first layer only to get the shells to squish together and still bump the temperature up by 5C.
What does the other side look like?
If you are not sure if you are under or over extruding then try these calibration clips to fine tune your filament parameters. The technique works very well for me. http://www.thingiverse.com/thing:1037301
If it is the bottom of the part and the first layer, then you can increase the first layer temperature by +5deg, also you can increase the first layer width upto 150%