Cura 4.2.1 Combing behaves differently between UM3 and S5

[V3DPrinting 11]

Hi to all

 

I am printing the same parts on both S5 and UM3E using Cura 4.2.1.

 

I have noticed when printing on the S5 that it performs retraction when printing the infill of the solid infill layers.

I have set the Combing Mode to "Within infill" on both profiles and have the same parameter (not printer related) on both profiles.

 

On the UM3 Cura has sliced the solid infill without any retractions between lines of the infill, but on the S5 there is a retraction between each line. See screenshot

The slicing has been done on the same installation of Cura.

 

Doing the slicing on another computer with Cura 4.2.1 provides the same results. Both computers were MacOS

 

I believe it's a bug.

 

Can somebody running Cura 4.3 check if it's still there ?

 

Thanks for the feedback

 

David

[Link 34]

Do you really mean infil or bottom layers ?, I do you have infil set to 100% ? If not you are looking at bottom layers. 

 

I very much doubt there is a bug as you describe. Likely you have a setting difference between the two profiles. Set combing to not in skin (I think you are talking about the bottom layers, not the infil) bottom layers are classed as skin, so you want not in skin. 

 

Also check things like 'retract at layer change' that would well be on in the profile where it's doing the extra retract. 

[V3DPrinting 11]

Hi Link

 

Thanks for the feedback

 

I used the wording "solid infill" as in Simplify 3D, but it is bottom and top layers in Cura wording.

I'm printing with a 60% infill in the current case.

 

I do confirm that I have the exact same parameters in the both profiles and Cura 4,2,1 behaves differently. So it is a bug.

I checked every single parameter which is not hardware related.

 

On the UM3 it combs within the infill, with no retraction

On the S5, it is like setting the combing parameter to "Off" or so.

 

I have attached the files for each printer.

 

Also I would like to comb within the infill (including the solid infill) and not in skin, which the parameter "Within Infill" does well on the UM3.

 

My post is to point out the discrepancy between the two behaviors. Note that if it is an non Ultimaker printer (I have a Mankati XT Plus) it behaves like on the S5.

 

I understand there might be a workaround with the "Not in skin" parameter, but if you look at the path generated, it overlaps the infill perimeter, which creates additional travel. See screenshot.

 

UM3E_model.3mf UMS5_model.3mf

[Link 34]

There is bug with 'not in infil' where Cura will it will either retract or comb when it shouldn't, I found it some time ago and discussed it on here. I don't think it ever got fixed. You can search for it user smart avionics looked into it at the time. Not sure if he is still around. But I just moved to not in skin to get consistent results. This could well be your issue

 

[V3DPrinting 11]

Hi Link

 

Thanks for the feedback.

Yes it's the same issue, but it is consistent, based on the printer configured in Cura.

 

It would be great to have it fixed by Ultimaker team, in order to get consistent results across the different printers.

"Not in skin" might be a good option, with a slightly longer print time, but not as much as with no combing  and without the hassles of the retractions.