Get rid of zilts

[glsf91]

How can I get lost of these zilts?

See picture:
You see 2 on the right corner and 1 on the left corner.
Problem is they are only coming when there is a travel from the inside top or bottom layer or infill to the outside perimeter in this case.
When the inside is empty or low infill, then there are no zilts. Even if there are retractions for every layer.
I used the calibration square from http://forum.makergear.com/viewtopic.php?f=3&t=3124

When I only use the 4 bottom layers and remove the infill and top layers, there are 4 zilts coming. For every bottom layer one. Above these 4 layers no zilts.

I tried a lot of things but they don't disappear.
I try to show it with the following screens. I removed the infill and top layers. Problem is the same as on the picture but now the zilts are only on the bottom 4 layers.

See this picture:

So even if there is no retract/extract action, the zilt is coming at the black arrow (start of (blue) perimeter).
I uses wipe of 8 mm in this picture. But not much difference when lowering this or switch off.
Extra restart distance of -0,2mm won't help (if there are retractions).

If there is a retraction for every layer then only a zilt is coming at the black circle. Also a travel from inside to perimeter.

The other 3 are on the other sides of the cube.

For the little cube it is not a big problem. But when printing other stuff, the zilts are on more places. Not very nice.

I use a Prusa P3Steel. 0.4 nozzle, 0,2 layer height. Direct extruder, E3D look alike.
I see this on PLA, PETG and ABS. Picture is of PLA (195 degrees).

[CompoundCarl]

I would suggest reading this: https://www.simplify3d.com/support/prin ... s-and-zits

It has some good suggestions and background info

[glsf91]

Of course I already took a look at this and tried a lot of the suggestions (and more). But with no good result.

Extra Restart Distance is mentioned. But I have also the problem when there are no retractions at all.
When I have retractions for every layer I only will get less zilts when making a high Extra Restart Distance. But then other parts of the thin wall are disappearing because there is also a retraction there and not enough extrusion at that place.

Coasting won't help because the zilt is occuring at the start of the loop. Not at the end.

Avoid the retractions won't help, because it is also there without retractions.

non-stationary retractions I have already enabled.

Control the location of the start points will not remove the zilts.

The strange thing what happens that a zilt is only there when extruder is printing inside and then continue printing at the perimeter outside. At that point a zilt is there. Printing a thin wall with retractions at every layer, but without infill or solid layers there are no zilts.

I also tried with Slic3r. Then I have no zilts, so it is possible without zilts. Only at one corner I see some distortion, but no zilts. But that is also sliced totally different then in Simplify3d.

[CompoundCarl]

My opinion is different than yours on about half of the items you mentioned.

Coasting would help, since it will reduce the pressure in the nozzle at the end of the previous loop. So it can have an affect on the beginning of the next loop as well.

Changing the location of the start points can also have a big impact since it will impact the time of the move (i.e. the amount of time the nozzle has to move)

I would also disable non-stationary retractions until you get your standard retraction settings working. That just adds another layer of complexity.

If I were you, I would probably just disable retractions completely in S3D and your other slicer and then print some simple parts to see what's causing the difference. With retraction completely disabled, you sometimes get a blob when you move between layers (since the nozzle oozes during the slow Z-axis move), but if you have several perimeters, you usually don't see that once you get to the outer one.

[glsf91]

Thanks for your help. I will try this soon and will get back with the results.

[billyd]

For whatever reason I have this exact problem on my Taz 5 too (which is similar to the op's printer).

It is related to retractions because I have found that if I create profiles with minimal retractions this problem is greatly reduced. (of course you get other problems not retracting enough).

The weird thing is S3D when used with my Makerbot R2 doesn't have any issues with zilts at all. I can retract all day long any way I want and the print comes out perfectly with that printer.

So I suspect it's a combination of the electronics and extruder of the Taz style computers that have a big problem with S3D.

I can use coasting and negative retract settings but with thin walls and small parts this creates HUGE problems in other ways. Meanwhile S3D and my Makerbot remain unaffected by any of these settings.

Something is seriously wrong either with these style printers or the way S3D works with them.

[glsf91]

After a lot of testing on the same object I saw the following:

In slic3r I have the same problem when putting seam position on random. A lot of zilts. On nearest I get a seam in one corner, but no zilts.

I can remove the zilts when changing the extract to a lower value. That means a less extract position after the retraction.
In the following I changed G1 E0.0000 F2400 in G1 E-0.8000 F2400 and the zilts go away.

G1 X108.061 Y109.475 E28.6289
G1 X109.475 Y108.061 E28.6907 ; last extract
G92 E0
G1 X108.061 Y109.475 E-1.3326 F3600 ; retract with wipe
G1 X107.983 Y109.480 E-1.3850 ; retract with wipe
G1 X107.491 Y109.480 E-1.7133 ; retract with wipe
G1 X108.537 Y108.433 E-2.7000 ; total retract 2.7 mm with wipe
G1 Z1.590 F1000
; layer 8, Z = 1.6
; outer perimeter
G1 X109.428 Y109.095 F6000
G1 Z1.490 F1000
G1 E0.0000 F2400 ; extract again for next layer
G92 E0
G1 X109.272 Y109.272 E0.0073 F1440 ; start of next layer

So changing the extra restart distance can solve the problem you should think. Only this cannot be done, because then other layers show defects (holes) because of lack of plastic.
Remember, I have only zilts on the outline perimeter when there is infill or solid layer inside. Not on a thin wall with nothing inside on that layer.

When I change the Start Points from Optimize to Choose start position, then the zilts are gone and I get the same result as slic3r. In one corner a little distortion. I think this is called a seam. At the corner the plastic is going a little inside. But no zilts going outside.

Coasting on won't help and is giving problems at other places because there is not enough platsic to finish that loop.

So it looks like I need a big extra restart distance, but only when there is a solid layer or infill inside and going to outside perimeter. And this cannot be done as far as I know.

[billyd]

Something else on my Taz I've only just noticed with Zilts. I am only getting them on curved walls. The straight walls are perfect. I have no idea why this is happening. Something to do with the electronics? Perhaps it can't handle driving three steppers at one time? (X Y and the extruder)? That's all I can think of.