The way this happens surprises me, is there some chemistry involved, or just initial cracks from the feeding that slowly gets larger when left under stress?
Here is an example from out Delta Tower, where PLA from Kjell & Co was left in the printer over Christmas/New year: We have had the same thing happening with other types of pure PLA in that printer.
Recently I saw this with Ultimaker gray PLA in an UM2Extend which had also been sitting unused for some time.
I have not seen this happening with Colorfabb PLA/PHA (which is much more flexible) or with any other type of filament that I have used.
Haven't heard reports of printed parts (put of pure PLA) cracking when sitting under load for some time too, as I can recall.
So I am curious, what are your theories on this, why does PLA seem to self destruct when left inside the bowden?
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