Object got knocked over?
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@Chriss I didn't look at the pictures earlier. Now that I have, I can see the problem - I've had exactly the same thing myself in the past. It's the overhang curling up at the edges. Increase the part cooling or re-arrange the ducting.
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@deckingman You have all of my respect but I do not agree here. The cooling works very well at all of the below layers/overhangs. The hotend tool is a bondtech assembly with cooling bla bla.... I do not expect that there technique do not work.
And the knock over happens always after 70-85mm. I would expect a earlier knock over if that would be a thermal issue.
Cheers, Chriss
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this yellow surface looks a lot like printbite. printbite requires bit higher temp than other surfaces so maybe that's your problem... trying 65 or 70C for the bed might solve your problem.
as for the
I would expect a earlier knock over if that would be a thermal issue.
actually, for most thermal issues it depends on the print temp so with the design of that tower it will curle up more or less depending on the print temp so whatever temp you reach there is a problem... also, just like overextrusion, things tend to stack up so delayed failing... also same nozzle "catching" at low height does not produce same amount of force to the base as when it does the same thing higher up etc etc..
IMHO you need to get that bed to at least 65 for that build plate, and you need to look at the print to see why it catched and on what, hard to tell that from images but in 99% cases, as said already, it is either "curled up" so catched by nozzle or overextruded so catched by nozzle
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@Chriss Well I'm not going to argue with you but that last picture you posted clearly shows the left hand edge of the part curling upwards.
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@deckingman I think that you see something which is not present at the actual part. I could make a picture from the x or y site. But that is not necessary any more, the reduction to 95% extrusion did it. The last print was successful now and the surface (outer wall) looks far better now.
I guess that I have a new job now, I will print it now with 96, 97, 98 ...
@arhi: It is a printbite indeed. I raised the temp already a bit, the adhesion is not bad at all. But playing with the temperature is a very good idea anyway.
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@Chriss said in Object got knocked over?:
@arhi: It is a printbite indeed. I raised the temp already a bit, the adhesion is not bad at all. But playing with the temperature is a very good idea anyway.
I use printbite for many years and I'm in love with it, but it requires ~10C more than what you can read about ideal temp for other surfaces (glass, glue, tack..) ... for e.g. I print PLA at 70C, ABS at 110C. Jason in his documentation writes PLA is 60-65C for e.g. but for me 70C works much much better. You do get a bit of e.foot with 70C but it holds on like no tomorrow
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@arhi I think that it is not a big surprise that the adhesion is fine at 70°C. PLA is more on the soft site at 70°C than on the hard site.
Ohhh my English is not the yellow of the egg at 4am.
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@Chriss you could check that your z leadscrews are still moving freely at the height you get the issue, a bit of binding might cause the bed to lower unevenly or not enough.
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@Chriss said in Object got knocked over?:
.......................... that is not necessary any more, the reduction to 95% extrusion did it. The last print was successful now and the surface (outer wall) looks far better now.
That's in line with what I expected when I made the suggestion. For info, you might find this piece of research by Michael Hackney of interest https://www.sublimelayers.com/2017/12/musing-on-under-extrusion-prepare-to.html
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@Chriss The bottom looks like you are not getting enough squish on the first layer. Adjust the Z offset to get the nozzle closer to the bed so that you can barely see the individual lines of the filament Even then, you might need to use a brim or raft or tabs on the ends.
