Cura 2.3 (Release) Bug - Massive Stringing on Supports

[DaHai8 74]

There does not appear to be any retraction performed between supports to supports and supports to objects, thus resulting in massive stringing issues.

[bagel-orb 61]

I've implemented it such that there shouldn't be any retractions for straight travel lines from support to support. When such a travel is not straight as to Avoid Printed Parts, then a retraction should be performed.

It does look messy sometimes, but the stringing never actually touches the object.

At least, that is how the algorithms were designed.

If it works differently then there is a bug.

I haven't seen any non-retraction from within support to within the model, though.

Could you send me your gcode?

t [dot] kuipers [at] ultimaker [dot] com

[DaHai8 74]

I'll recreate the STL file as I've already deleted it.

Buy I have a question about this approach of no retraction between supports:

1) The stringing puts pressure on the supports, doesn't it?

I found my thin supports fell over - I believe because as the head is moving and stringing it's pulling on the support it left behind. As a result, my print failed as the thinner support towers fell over (so I tried a raft, but that issues is in a different post)

2) With strinning, the filament is oozing and being pulled out of the nozzle. So when it reaches the next support tower, it starts printing with no filament at the tip and so prints nothing for a few millimeters. So the target support is weaker.

Other than reducing retractions, I think the Cons outweigh the Pros.

Perhaps a maximum distance to do travel between supports without retraction? So short distances would not retract, but longer ones would (user defined)

Thanks

[FahrerO 0]

this issue seems not to be solved in cura 2.5?

[jernn 1]

I've implemented it such that there shouldn't be any retractions for straight travel lines from support to support. When such a travel is not straight as to Avoid Printed Parts, then a retraction should be performed.

It does look messy sometimes, but the stringing never actually touches the object.

At least, that is how the algorithms were designed.

If it works differently then there is a bug.

I haven't seen any non-retraction from within support to within the model, though.

Could you send me your gcode?

t [dot] kuipers [at] ultimaker [dot] com

This stringing is not harmless at all. There should absolutely be an option to retract between supports. Not only does the stringing sometimes make supports WAY harder to remove, long strings pull filament out of the nozzle and waste it, in addition to throwing off what the machine thinks it's actually extruding. I'm definitely done using Cura until this is fixed. Honestly baffling as to how this got through QA.

[jerry_nz 0]

+1 to this... I'm going through and testing different slicing products and this is exact issue killed my first test prints :(

[bagel-orb 61]

Maybe you should update to Cura 3.2.

 

This problem is about something which only happened in the Cura 2.3 beta thing.

[jerry_nz 0]

oh hey!  and apologies!  i swear the title said 3.2 late last night - sorry about that

I'm actually already using Cura-3.2.1.  It looks and feels very professional compared to other slicers which will remain nameless  

 

My problem with the current scheme of no retractions with support-to-support travels (along with other peoples complaints) is that some of the time the strings detach - then the fan blows them around they get caught in the main print and stick there - this seems to happen multiple times and makes post-print clean up a fiddly nightmare, especially on delicate prints.

 

My current work around that I'm formulating is to make those strings bulkier somehow - so they can't detach.  Or avoid supports completely and use meshmixer to create them.

 

I guess my question would be - is there space/time/energy in the Cura development to add "retractions with support-to-support travels" but as a choice to the user (with the default settings as the current released so it doesn't trip anyone up!)

 

I ask this, as it was not hard to find multiple posts about this problem :(  

 

____

 

edit:  i see the original post was from 2016!  apologies again!  i promise to not post so late next time!

Edited February 27, 2018 by jerry_nz

[bagel-orb 61]

I could probably implement this without too much effort, but the Cura team is lagging behind on handling github issues and pull requests, so I fear it would take too long.

 

If you respond to this thread again I might give it a shot tomorrow.

[jerry_nz 0]

If you managed to find some time I'd obviously be the first in line to test it out of course!  

And I completely understand about the github issues/pull requests - easy to get bogged under in such app developments!

 

thanks for your ears @bagel-orb

[bagel-orb 61]

Implemented it!

 

You can follow the progress here: https://github.com/Ultimaker/Cura/pull/3411

 

You could beta test the next release; the Cura team doesn't really distribute pre-beta builds...

[jerry_nz 0]

You sir, are my knight in shining armour - thank you! 

[DSX76 0]

Landed here while looking for answers to the same issue. Thanks for implementing this, looking forward to the release!

[MBRPrinter 0]

Also experiencing this issue currently on my Anet A8! Thanks so much for implementing, looking forward to the release. When I see it I will test the parts I am currently running and advise if it helped. 

 

Thanks. 

[codymac 0]

This is happening for me in Cura 4.1.  Was the change reverted?