Hi.
I was print the pressure advance calibration tower with Acc=2500. Before the sharpness of the edges are good, the printer make these edges.
What is the problem? Extruder, Hotend, Filament?
My ender 3 can print with a acc of 3300.
Thanks guys.
What is the problem? Extruder, Hotend, Filament?
My ender 3 can print with a acc of 3300.
Thanks guys.
For this test tower it is intended to go this way.
You measure the distance from the bottom up to the point it is the best result and you calculate the pressure advance value.
It is maked. Ater i printed a new cube with the calculated value. But the edges are not sharp, outer corners and the start after any edge is damaged and verry thin some millimeters. The filament is stretched. After the line has the correct thickness.
When you print a test tower as described in the link above, you will always get the variance of different pressure advance values. This tower is for finding the best value only.
You may test with a usual test cube.
I print many towers for many filaments. I found a good value for every filament. The best between sharp and round corners. The used filament from the picture above, has a value which is in the tower best selection before the layers are damaged after the edges. But when i print a real cube with the calculated value, the corners are not sharp and the filament is stretched and verry thin.
Here is a new example.
I used this edge. Calculate the value and print a new object with some extrusion an the sides. I forgott this of my work. No picture yet. From the first to the last layer the edges round and a bit over extruded and after some edges the layerst complete destroyed the first millimeters.
Sounds like you just need to lower the PA value a bit until you settle on one that works well for “real life” prints. I’ve found that when following the PA calibration instructions precisely, when I try to pick a PA value based on the very last layer before noticeable extrusion issues in the corners of the test tower, that value usually tends to be too high for normal printing.
The por layers after edges i read on the web are skipping steps from the extruder? If i have understand. After i set the acc to 2500. But i cant hear any from the Extruder.
This are underextrusions which comes from my Hotend? Or can i get better results on another hotend which have more flow?
It’s hard to tell from your posts, but it sounds to me like your pressure advance setting is too high. Try lowering it and see if you get better results.
I know that pa is too high. I changed to lower value. But what is this phenomenon? Does klipper reduce the flow to much on edges? Because after about round 10mm there is a blob on the inside of the line and after then the line looks normaly good again. Doesn’t the flow actually have to be higher at the beginning?
I’m not seeing what you’re referring to.
I can no longer reproduce it and the example is in the garbage at work.
What I mean after each edge the wall line is stretched until it almost destroyed. After a few millimeters, a small blob will appear inside the wall line and the wall line will print neatly.
That doesn’t sound like it’s being cause by pressure advance. I would first try either increasing the nozzle temperature 5-10 degrees, or reducing the print speed and see if that helps.
I increased to 220 degrees. But I see a phenomenon at 100mm/s on all the last prints. I didn’t see this because I was fixated on the edges.
I think this is the accelleration. It is the first wall line top of the last solid layer. Every print the same. I will reduce the accelleration now an print again. But why is klipper telling me the maximum on accelleration it can be if it is not possible to come close to exhausting it?
Is this the pressure advande test tower?
If yes, what values do you enter?
I’m inclined to blame the slicer settings used for the test tower. I usually run this in vase mode with 1 or 2 bottom layers and 0 top layers. That means the corners on the top of the “feet” are printed in air because there’s no layer on the top of the feet to support them. It’s hard to tell from your photos but the orange one sorta looks like there might not be a solid layer on the top of the feet. If that’s the case, then that might be contributing to the problem.
But all the other layers look really clean to me, so I would try some “real world” prints with more typical slicer settings and see if the problem persists.
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Yes thats right. But i changed to first 3 solid layers. This is the tower with my settings which i used before for all my prints in this color. I changed only the temperature, speed, infill, top layers and temperature.
I do not get it more. Another Filament and another object. Picture shows second and third layer. Extruder checked. At 100mm, 2mm overextrudes. So no under-extrusion. Print speed here 60mm/s. Temperature 205 degrees. Layer height 0.2mm and PA is disabled.
Looking at the line-width and line spacing it more looks like severe under-extrusion.
I’d suggest the following:
- Remove PA from config / slicer
- Do some hot-end maintenance, e.g. clean nozzle, inspect heat-break, make sure everything fits well and is well aligned
- Make sure your E-steps are properly calibrated
- Make sure you do not have any funky slicer setting activated, e.g. wall overlap compensation, dynamic flow blabla, dynamic acceleration blabla
- Make sure your flow / extrusion modifier is 1
- Make sure you have a proper extruder speed setting (and no, extruders can’t do 100 mm/s)
Now print some simple test squares and make sure the solid layers are proper:
- no dark spots / holes → under-extrusion
- no ridges / roughness → over-extrusion
Once you are there start tuning PA
Edit:
Depending on you hot-end / extruder and filament, 100 mm/s may be already too fast and you will never reach good results. The recommendation in the PA tuning guide is more a rough guide-line. The faster you print, the more exaggerated the effect will be visible.
It though makes no sense if you system cannot live up to this speed from the very beginning.
Also, if you expect proper help, it would make sense to post proper information:
- Filament type
- Information on your extruder
- Bowden / direct
- PA values your tests recommends
- Used settings, e.g. speed, acceleration, square-corner velocity
- Post a klippy.log, so that the knowledgeable people can check if something weird in there
- etc