Hi all, i don't know whether i am right here, i am looking for help .... i have an aluminium 8mm thick heat bed ... the sensor is on the heating pad, therefore the measurement is usually way off. For PLA, i used 75C where on the buildplate it's 55ish. When the part fan runs, it further decreases resulting in benchy detaching, ... what can i do about it, any clues?
#Benchy Detach
modern saffron
limber hare
Hi, here is some good post about build surface preparation
#slicers_and_print_help message
modern saffron
thnx 🙂
modern saffron
checked all the points ... the voron calibrating cube ended properly, but the benchy always fails in the upper region (detach) ... surface is clean, temp is high ...
besides of that: acceleration too high?
limber hare
.... not a coincidence... (?)
No, print is curling up at the bow. Cooling is not keeping up.
Slow down.
How fast are you trying to print it?
also show the bottom
you may be too high.
modern saffron
i was pinting at 480m ,,, slowed down to 240 and the bow looks nice now ,,, I did a brim for the benchy and it failed at the chimney. Meanwhile I have also lowered the first layer>
lowered autoz offset from 0.58 to 0.62
modern saffron
... but the top layer is reeally rough
modern saffron
modern saffron
I'll check ellies guide
limber hare
That looks overextruded 🤔
limber hare
the wall look okay, only the top is rough
It looks overextended IMO
modern saffron
okay? reducing the rotation_distance (currently 22.67895)?
limber hare
okay? reducing the rotation_distance (currently 22.67895)?
Try decreasing flow in slicer
extrusion multiplier
modern saffron
okay, thanks for your help
limber hare
What slicer do you use?
modern saffron
SS
limber hare
modern saffron
?
limber hare
Yes, that's the issue
limber hare
Seems so
limber hare
Try decreasing flow on top layer. Superslicer should allow for that.
modern saffron
okm will do, thanx
craggy ginkgo
You could also save your config and try one of Andrew Ellis's slicer configs. He has a few from memory . 12mm3/s and 24mm3/s decorative, as well as PIF 12 and 24mm as well all at 45degree to bed setup. Works well for me with a bit of tweaking on the accels to suit your own build of course. If it makes not difference, simply throw them out and continue with your own profile. Andrew also talks about being wary of new versions. So you might try his suggested and heavily tested version ... and then you can update your versions until it breaks lol.
modern saffron
I've tried some runs with decreased flow but no change ... I'll read into Elli's config and continue testing .... the wall of the cube are smooth and almost perfect, .... the only issue is the top layer - so yes, ... until it breaks 🙂 .... thanks again for your help
modern saffron
two problem seem to persist: top layer looks bad and the other is that - even when the benchy sticks very well - it detaches in the higher regions. I've checked whether something is touching but no observation ... it just detaches miracously i.e. when the chimney starts
tried ellli's profiles but no success
any clues?
craggy ginkgo
what material are you melting?
modern saffron
it's PLA, .. the wall come out beautifully, however the top layer is really not good
i have made some brim and some parts remain on the bed, while the benchy always detaches on the chimney level (the top layer also looks ugly)
modern saffron
the last picture was the attempt to use ironing ... it obviously did not give the result i've expected ...
modern saffron
I havee reassembled the stealthburner and found a loose screw - therefore back to testing
modern saffron
I've observed that ironing can kick the part and detach it - nevertheless ... the top layer remains ugly vs. my other printer which gives the result i expect:
(left side> nozzle impact just before ironing)
limber hare
To me it looks like you are heavily overextruding on top layer.
Can you set flow for top layer separately?
Also, how many top layers you use?
modern saffron
using Superslicer Solid layers on Top 6, Bottom 5 and it enforces 100% fill volume
On Top surface, I have "only one perimeter set"
modern saffron
is there a way to control extrusion factor on layer basis (i.e.SS)?
ocean pulsar
An Extrusion factor that low usually indicates there is a problem elsewhere. The normal range is about 92-98%. Are your E-steps calibrated properly?
If you are printing just one layer to test this, your nozzle might also be too close to the bed.
I recommend you follow this guide:
https://ellis3dp.com/Print-Tuning-Guide/
To properly calibrate the extrusion factor, you need to print over a couple layers of infill. This makes sure the distance of the first layer to the bed has no influence. This is also described in the guide (probably much better than what I do here)
modern saffron
Hi vwagner, thanks for your reply. The E steps were okay and i was able to correct the issue with the extrusion factor: the frst layer was way to close to the bed for a 0.8 nozzle - i have corrected this and it looks really nice now. But strangely, it looks like only the top layer is affected by overextrusion, rest is quite okay. i followed elli's guide already. i experienced anothe strange thing were steps were skipped and everything was shifted for around 4 mm ... hope this does not occur again, the reason is unknown
i've noticed that in Superslicer, top and bottom layer pumped an extra 40% extrusion width. i am playing around with the values there - hoping that it gets better
ocean pulsar
If it is just the top layer that is overextruded, you can reduce the EF just for top layers
In SS you can find it under width&flow -> flow ratio -> top fill
But still, 60% is way off
modern saffron
success .,.. was able to fix ... 0.9 extrusion multiplier, set the top also 110 instead of 140 ... now it looks good, thanks 🙂