Wraping NOT lower layers but higher ones with ABS

[Boris]

Hello, everyone.
I know problem when lower layer of ABS is wrapping. With insulating bed I have no wrap of lower layers. Bed keeps plastic very well and strong.

So, problem with higher layers - it's wraping as on screenshot, so my extruder strikes it and moves after long work on supports.
But around supports seems not wraping at all ! Why ? What I'm doing wrong ?

I rised ABS temp by 250, made walls(forgot right word ) not 1.2 but 0.6, and use 100% fan power.
It helped me alot but result still isn't perfect.

So, I have 2 questions:
1. Why every tutorial suggests low down plastic temp as much as possible(210 for ABS). Noobe explains why I should do this.
2. What I doing wrong ? How to eliminate that wraping on picture during printing process ?

Thanks for any help.

(Felix 3.0 with 2 extruders, Cura Engine 0.150, ABS 250degree, bed 95degree - if I try more than 95 I've got "Heater Decoupled" on printer screen)

[satoer]

Image looks like over extruding to me.

[Boris]

Wow !
Never heard this term before. But it's sounds very reasonable.

So, do you think I need to less feed thread ? By 85%, for example ?

[satoer]

Well, try to print a simple object like a cylinder. While printing adjust the "Flow speed" and let it print a couple of mm. This way you can find the perfect feed rate for that particular filament.

[Boris]

oh, it's totaly fail
Sometimes I've got perfect models(see back of cat figure)

and sometimes it's... it's... have no decent words to describe(see blue mountain)
Yes, it's a different plastic but believe I've fade many perfect blue cats before.

What os going on here ? what is that... warping, all these holes, or what ?

[seaton]

whats the temperature you have it set to, maybe too hot? is it popping if you extrude in air?

and possibly under extruding.

Try a thin wall calibration and then see how you go

[Boris]

I've try 230-250. And best results for me is 235(at 250 sometimes brown melting happens).
So, there is 245. During printing I changed cooling speed from 0 to 100% with no any visible results.
Also during printing I cnahnged flow from 80 to 100%.

Honestly flow 100% is too much for my models. As you said before I've got overextruding wiht 100%, so 90 is best for my other models.

Wall calibratuion gives perfect results - look at black cat's back. It's near perfect.

[Boris]

Oh... it's hard to explain but I'll try.

So, here is screenshot from zBrush. Take a look at this huge rock over cave entry.
The lower part need supports for sure.

The photo is the result of printing(12x12x12 cm aprox). So, this is not problem of this model but every my model but here I can exactly explain what happens.

At 3rd picture - the sketch from photoshop I'll try to explain my vision of problem.

The "side" part show the slicing. Red lines is supports. Before begining of huge rock everything if perfect ! not any issues. But... When we got layer 100(no matter which exactly) when supports ends and rock begins - this parts begin to wrap
I think it's happens because extruder print mountain layer more than 1 minute and rock hanging part becomes cold. So, time by time second extruder strikes this rock(sometimes even blue cooler cover) and with horrible sound it falls
Everymodel ! There is not problem of second extruder or cooler cover but wraping of cold layers.

Both ABS and PLA. ABS is wraping more.

Do you have same troubles, guys ? Need any ideas how to print hanging parts with no wraping during printing.

P.S. After it falls printer still can print rock anyway. But I want to get rid forever of this wraping anyway.

[Boris]

Oh... still no solution
Some parts are wrapping everytime.

[Hugues]

Why do you want to use ABS ?