Printer goes to insane speeds and then starts skipping
So this is my SuperSlicer speed settings for ASA. Also attached, the offending layer. According to SuperSlicer, it is the "Top Solid Infill". At least when I toggle it, the layer lines do disappear. I think my settings are right and that it is set to 50mm/s. Anyway... the print goes fine till this layer. Then all of a sudden, it speeds up, like a lot. I think the hotend can't keep up and the extruder starts to skip to the point where the filament just jams. The problem is, I can't figure out why the print speeds up on this layer. It gets even weirder for me: I think it does a first pass at the intended 50 mm/s followed by a second pass at those insane speeds. l to be confirmed when I finish my current print, though I am 90% sure. Maybe I have activated something, somewhere, I shouldn't have?
23 Replies
So, the first layer prints fine then? Then it works as intended. First layer is 100mm/s as you put in the slicer, after that it starts to print with 300mm/s. And thats very fast with a .6 nozzle and LGX/Mosquito. Try reducing the print speed to 200mm/s and go again
Just repeating what we said in General: The 300 is there for show. The speed is actually capped by the flow rate.
And the print never actually gets even half way to that speed.
Or at least it shouldn't.
Maybe it has something to do with the vase mode. I don't have enough experience with vase mode, so no idea if there is something special to consider in the slicer tbh
Something is wrong with the speeds. If you look trough the gcode, the speeds tripple starting with the gap fill in layer 5. That would explain the first slow pass and the second fast pass. From there, the print speed is nearly 300mm/s
Could be a bug, could be something with vase mode. Maybe try lowering the print speed and go again. Seems like it just ignores the volumetric limit
Thanks for pointing that out.
I am now printing a normal part, no vase mode, to see what happens.
If it craps at layer 5, I'll down the max speed to 150 manually to see what happens.
So I am no longer in vase mode. I was able to manually up the speed till the extrusion was at 200 mm/s reliably. So this time I set all speeds manually:
But after slicing:
It won't do more than 100 mm/s.
Even with layer time set to zero.
why are you changing your accelerations? Your accelerations should be based on your input shaper graphs and you just leave them alone.
Don't these override the input shaper?
If so, then what do I change them to, so that the input shaper takes precedence over them?
input shaper - a tool to figure out what your machine's acceleration should be
[input shaper] - your klipper settings that act as your machine maximums
acceleration in slicer - what you are requesting the machine do. You can request 20000000, but if your klipper setting is 1000, you will only get 1000
I know what input shaper is.
I have already run the shaper_calibrate.
I always assumed the slicer would override the results from the printer.
So I can just max out the values in the slicer and run the calibration and then just let it rip?
Since the printer will always override the slicer?
Or do I have to change something specific in the slicer?
Note: not that I want it to. Just assumed this was what happened. That slicer would trump printer.
nope, it is backwards. The slicer requests, klipper decides if it needs to change it
if I am understanding you correctly, yes
Ok. So set something absurde like 20k or something in all accell fields?
Just to make sure before I end up sending the print head to the moon 😄
I personally have the same settings in my slicer as in my klipper config. But you do you
Is there an explanation how to interpret the results?
my main point was, if you are playing around with speed, you don't need to mess with accelerations
I see data being sent out in the console.
You're totally correct. I was hoping that upping the acceleration would help me shave off some time.
This is the wrong way around. Set the print to what doesnt let it rip itself apart
Set the slicer accels for quality
I'm the slicer you have control per line type etc
Use generate shaper graphs macro and copy the frequencies for mzv to your config. This is not automatic. Use the suggested max accel in your slicer settings
This is the result. If I understand you correctly, the relevant bits for me would be these two sections?
Recommended shaper_type_y = mzv, shaper_freq_y = 30.8 Hz
17:22:01
To avoid too much smoothing with '3hump_ei', suggested max_accel <= 2100 mm/sec^2
Recommended shaper_type_x = mzv, shaper_freq_x = 53.0 Hz
17:21:46
To avoid too much smoothing with '3hump_ei', suggested max_accel <= 6700 mm/sec^2
This seems to define the max for X and Y, though SuperSlicer does not have X and Y.
I am a bit lost. So the firmware overrides the slicer.
But I shouldn't just slap in a high number in the slicer and let the firmware do its thing, is that it? In the slicer I should set it to something lower, that I know will not create issues? And then let it run and the firmware will do its magic?The slicer can change the acceleration during the print, for example to use higher accel for infill than for perimeters
Klipper config is a hard upper limit
Use y accel, because it is the lowest
Check the graphs it put in the input shaper dir