Which setting to eliminate zits on this part?

[Motolectric]

Hi,

I've read the posts about adjusting the retraction and coasting settings and understand their operation.

But my part has very specific defects and it takes 7 hours to print.

Other than these few issues it is coming out beautifully and really shows the value of S3D.

I have attached an image showing the preview of the part.

At each point where the red line meets an inner wall I get the defect.

I also get them where the red lines converge in the inner corners of the 2 mounting tabs.

If anyone has an idea of which setting would most affect these issues I would appreciate a pointer.

As it is, I have to leave it printing all night and need to get it sorted quickly.

Thanks for any help/pointers.

M./

battery.tray.defects.png (202.64 KiB) Viewed 6264 times

[CompoundCarl]

Can you post your factory file? That will make it easier to see what settings you are using

[KC_703]

Zits can also be overextrusion and printing too fast. Lower the multiplier by 2-5%. The outline underspeed percentage will depend on you machine. I find a percentage which prints the outermost outline at 20-40mm/s works will for my machine.

[Motolectric]

Thanks for the replies.

I decided to print another as the exterior of the model is fairly presentable for its use.

I made 2 small changes to the process file and things got worse.

I added a bit of coast and I reduced the retraction from 2mm to 1mm, other than that attached file is the same.

The previous print had the same defects in the same places but the excess extrusion was less.

I have 2 shots of the walls and corners and as you can see they are stellar.

So I think if I could adjust something to remove the jumps across the model that might make things golden.

Any help is appreciated.

[Motolectric]

These are the images of the outer surfaces, they come out very nice.

Thanks for any tips/hemp.

M./

[CompoundCarl]

Go to the Advanced tab and enable the "avoid crossing outline for travel movements" option. That will make the extruder route around the outside of the part instead of across the gap in the middle.

[Motolectric]

with and without the file setting

Thanks Carl,

I did that and the preview still shows the some red lines going across the open area to the back walls.

Certainly looks like it will be cleaned up from the original though.

So, thanks for the comment.

I will try it tonight and see how things go.

Would be nice to get rid of the defects at the back wall though.

M./

[KC_703]

So the zits are gone?

Now its just the ooze on the interior of the tray? Try lowering the extrusion temp a bit... that should reduce the oozing.

Is this 1.75mm filament or 3.0mm filament? 1mm difference in retraction seems like a lot... IMO, the 2mm retraction seems more correct. I'm at 1.8 for 3mm filament.

[Motolectric]

Haven't reprinted it yet to see. Will do it tonight.

I was just commenting on how the preview changed and that it still showed the red lines traversing the open area to that point on the back wall.

I will put the retraction back to where it was since as I mentioned things got worse when I added coast and went from 2.0 to 1.0 retraction.

Thanks for the comments.

M./

[usagi]

I did that and the preview still shows the some red lines going across the open area to the back walls.

increase the detour factor to 30 or 50.