Help with apparently too hot printing
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@fcwilt you are missing out my friend! Even on direct drives, I've found a small amount helps
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@fcwilt, I started out with a Bowden setup (CR10) and PA is a noticeable (significant) improvement for that (even though I know people who use no PA). My second printer was the CR10 S5 which has a Bowden tube of probably close to 800 mm. It would be nuts to expect reasonable prints from that without PA.
I am starting to work with direct drive extruders now and PA can help for the discerning person but isn't absolutely essential. It might be essential if you are doing soft stuff like TPU but haven't tried that yet. -
Final update:
Different filament did the same thing with curling at the points of the corners.I had previously reported that support at the corner edges helped but that one corner still had problems. I changed the X/Y/Z distances between support and the model in Cura which got me a solid support and no curling.
To sum it up, the two big issues where pressure advance and support. I am sure I printed without support to at least 60 degrees of overhang before but maybe I didn't and maybe the shape of this model causes issues earlier but setting the support angle at 50 degrees and having the support close enough to the edge fixed all the issues. While the side angle was 45 degrees, the edge where two 45 degree sides meet must be just under 55 degree overhang.
While I did go down to 180C from my normal 200C nozzle temp for PLA, I do not know if that was actually necessary given that support was the big issue. It did help when there was no support.Thank you to everybody that helped me sort through this issue !!!
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Well well well ..... I think I jinxed it when I said 'final' update.
So I kept thinking about the blower fan I use for model cooling. Yes, it works, yes I can reduce the output and it turns nicely even at 25% .... but I just couldn't leave well enough alone.
I removed the fan so I could gauge the output a bit better and there clearly was output. Put a new fan on to compare - same thing.
Still wasn't happy so hooked up a power supply, hooked up one of the fans and got the same output.Contemplated life a bit and decided that still wasn't good enough!
I dug out yet another new fan and hooked that up .... the output was probably 4 times as much air !!!!I will attempt to print one more of the fence post caps but this time with proper air flow for cooling.
Boy will I be pissed off if it prints perfectly even with no support!
I will also get myself a new batch of better quality fans (this time ball bearings) !I can't believe that there is a good chance that I spent 3 days or so printing because of a fan issue, the very first thing I checked and suspected!
All fans were marked as 24V and I use 24V but either two of the fans were 36 or 48V or defective (while behaving just fine except for low rpm)
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If tuned correctly PA makes a world of difference printing fast.
@jens55 they could just be worse fans, unless they're the same brand/model. Fans are not equivalent even if they're the same size. Glad to see things are moving in the correct direction
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@luke-slaboratory, same brand of fan ... all from the same batch I ordered
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@jens55 said in Help with apparently too hot printing:
@luke-slaboratory, same brand of fan ... all from the same batch I ordered
Chinesium?
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@phaedrux, you bet
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@jens55 Yeesh. Unlucky
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@jens55 some fans does not like being pwm'd. Try changing the switching frequency of that fan when you declare it in config.g .
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@mikes, I think you missed the part about me setting up a DC power supply to verify the fan operation with straight DC. I might not have been clear.
BTW, the model printed just fine without support and proper cooling ! There are still some edge artifacts but I am positive they are related to uncalibrated pressure advance and they are very minor.
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@jens55 nice one! Happy you found the problem! Take your time and go into calibration steps for extruder steps, PA, filament flow and you are good almost for ever. At beginning i skipped steps because i tought they were not needed, but in the end the difference is remarkable. More if you try to speed up things.
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@mikes , this is an example of my corners now:
The corner is on the right side and is perfect. I started a separate thread about trying to reduce the oddities of the seam that you can see to the left of the corner.
