This is an interesting one if anyone have seen this before. Basically printer nozzle will block when it print to triangle grid layer, no error message and printer will keep print model in air until it finish.
I’ve designed this sink strainer for home use and iterated many versions and previously they print fine. Until I change the bottom to triangle like grid, then printer will end up nozzle clog at few layers after print triangle grid.
Initially I thought it was my extruder / nozzle block, I
- cleaned nozzle (pin clean, hot wrench clean)
- cold pull
- changed to brand new nozzle
- open and cleaned extruder
- Change different material f(rom ASA to ABS)
Tried all these, Seems non of them solve. Then I did normal print a scaled up benchy it did perfectly without issue. I start to think it is the model. Then I reversed the model print, yep it clog the nozzle at few layers after start printing triangle grid. And printer keep printing in air till finish.
Any ideas?
What’s the flow rate for the triangle infill?
Assuming you combine the infill and use a wide width it could mean the hotend just can’t keep up.
A fix would be to reduce the speed for the infill or the max flow rate in the filament settings.
With a high flow rate it could also a temp issue as the huge amount of filament going through the hotend might not get hot enough.
Once it struggles too badly the extruder can start grinding or just clicks…
Filled filament can be really bad here…
Are you sure it is a matter of a blocked nozzle and not a matter of the filament being eaten by the extruder wheels?
Once you have a big enough dint missing in your filament it won’t go anywhere.
Did you ever check how this part of the filament looks when taking the extruder through the cleaning rounds ?
It looks like this problem: P1S Stops extruding mid print
After the initial filament load is used up, nothing extrudes anymore. Very small parts will print, bigger parts fail without any error.
I’m discussing this with BL support, so far it looks like an extruder motor or TH-board being faulty. So don’t blame your model just yet, see if it’s the size of the model (i.e. the amount of filament used) that makes a difference.
Flow rate is using default Bambulab ASA (0.95) as per generic Bambulab ASA 0.4 nozzle setting.Pretty much everything as use default ASA settings and “0.08mm Extra Fine @BBL X1C” preset (except support).
Just got a new print (upside down) and it also start making this at triangle grid layers. Did a purge and cold pull (using same white ASA), it came with slightly brownish colour. Looks like a light burn of filament. And nothing found in extruder gear.
The ‘wall’ between triangles are 0.5mm so there is no infill in there. Could this be a problem?
That’s almost the same as what I’m experiencing. Very interesting of mine is the failure is weirdly consistent and predictable.
Until last night, I changed the ‘triangle’ grid pattern to a bigger hexagon with 1mm spacing of the pattern, it passed the grid print for the first time. But… failed with same issue close to 90%, sadly.
An interesting thing on extruder not sure if its same to everyone own P1 series. Default extruder spring tension seems to be at maximum point the first time I open the extruder, i.e. the screw controls the spring has been set to the tightest point and making spring very ‘squeezed’. Haven’t doubt about it as I was fine printing for the last few months until I saw JohnnieWalkerBR’s first post: P1S Stops extruding mid print
Could you guys please post some pics of the slicer preview for the layer(s) in question here?
And if possible also for two or three layers below that.
Especially for the speed and flow rate.
In the above pic I can see quite a few retractions and very short moves…
If, for example, the flow rate would be rather low and the nozzle temp a bit too high the filament could overcook.
On the other hand, if the layer height is very low and the flow ratio too high it could cause excessive pressure in the melting chamber - forcing the molten filament up into the heatbreak and massively increasing the friction there.
In return the extruder motor stalls and/or some overcooked and hard filament chunk fails to get through the tiny hole below.
Just for fun could you try something?
Since the failure seems to happen around the same layer every time, hit the silent bottom a few layers before it can happen…
If it still fails the same way when ‘crawling along’ it is doubtful the issue in your hotend or filament…
Here’s is the 3mf file with the settings having the issue.
https://www.dropbox.com/scl/fi/tozxkqppdwdnzfeds2v46/SinkStrainer_V5.3mf?rlkey=ehbp3wajwqugbh2zlwarmlyo7&dl=0
At around layer 138 the nozzle blocks and start to print in air.
It might be less likely a filament issue as tried another scaled up 3d benchy using same slicer settings and using approx same amount of ASA (approx 31g similar to this) prints without issue. this spool of ASA quite fresh and the other black ABS I tried just print fine.
Noticed in failure came out they have lot of spikes (circled in pic), can tell what’s causing it
Everything looks clean, looks fine to me…
Makes no sense to fail with a blocked nozzle…
Download does not work, says unsupported file format.
so, have extruder gear loose little bit, running for few days with the model and other prints, haven’t seen any failure yet. What i did was:
- lose the extruder gear quarter turn backwards (my P1S gear shipped with fully tightened and can see the spring have no room for gear to move)
- cold pull
- recalibration
How i came to this was when I did cold pull before, instead of came out with a snake shaped filament, I was getting a broken end filament. (I did use my hand to help extruder not to do it too hard to break it). Even if i open and cleaned extruder, changed to brand new 0.4mm hardened steel nozzle. Didn’t suspect this before. It ended up like this (Didn’t have a photo of the actual one, this is very close)
After losen extruder slightly, it came out cold pull much better:
So what could happened was my extruder too tight, when it did retraction , i guess extruder could probably break filament. Blocked nozzle will make it just worse until a full cleaning from back side of nozzle (cold pull etc) is performed.
cold pull param I use: Bambu generic ASA, heat to 240 DegC, cold pull at 120 DegC
I replaced the TH board, that fixed my problem.