bambu labs A1 with AMS lite side positioned beside, A1, and top top mounted, both prints used either elegoo/3dhojor matte filament, stock printer settings, ABDELat ultimate gridfinity boxes printed. 4 prints with 1 successful, the other 3 came undone once the walls of the container started to print then spaghetti party. any ideas? this is the end result of what my issue is. bed adhesion is great, some very small extrusion variances on layer one and sometime 2 but no real issue . infill is perfect but when the top of the grid box [where the “wall layers” would begin to start [not sure what layer in gcode] things seem to go sideways. the filament begins to not adhere and the stringing begins. i printed 4 different version of ABDELat ultimate’s boxes and 3 prints errored at approximately the same point [picture above].
i switched to single spool top mount and changed filament as well as print [layercake’s parametric container done in Fusion 360] which turned out much beefier than the previous prints and with the same settings as above prints [0.4 mm nozzle size and a layer height of 0.2 mm] which is recommended by both creators. first print was perfect. a bit tighter on the grid due to specs but what i wanted. reprinted the exact same box and at a higher layer the same thing happened again. not sure what is going on here.
sorry for the huge post but wanted to give as much info as possible and avoid the vague question with no references.
print settings:
220c filament
65c bed
Bambu Lab .04 nozzle
textured pei plate
0.20mm standard @BBL A1
layer height 0.2mm
first layer height 0.2mm
full calibration test run, filament loaded and unloaded properly.
i live in florida with high humidity but all filament came straight out of the cryovac package and onto the spool.
Up to the point were the print goes south the print looks perfect, you have indicated that this occurs at the same place on each print that fails. Have you checked if something is jamming your Z access at this height causing the hot end to jump up and skip a couple of layers. Try printing a small block set to 100 high and watch the print to see if your Z axis does anything different at that height. I see a bad line re-occurs at approximately the same distance apart as the print grows higher. Is your belt between the two Z screws tensioned correctly?
See this link to the Wiki to check your belt tensions
I know you said the infill is perfect, but just in case, did you look at the infill at the failed layer (in the Preview) to see if there are any infill lines printing mid air, meaning there is nothing from the prior layer for the lines to deposit on, and the lines are not straight so it can’t be bridged. If it’s caused by some infill lines printing mid air, then in general increasing the infill percentage can fix it.
You need to pull off that plastic cover under the bed & look for filament in the bed rail slots.
Not only is your print splitting at the same place every time, you have an underextrusion about every 10-15mm.
that was actually left over from another print. i keep the rails clean by pulling off the rail cover frequently. the poop can is to the left and i had just moved the printer to the table and didn’t have it in place for that picture. great eye.
is the under extrusion you are referring to in regards to both grey prints? i have never had a print fail then continue and finish like the one at the top.
i just reprinted the same box and it came out perfect, that is what is baffling. if it was consistent i could maybe hone in on something more specific.
thank you for the input. i will have a look at the under extrusion issue.
about 3mil from the top left of the print seems to be the place where it goes all wrong. i just printed this again and watched the layers and layer count and the box had no issue and came out perfect? so strange. thank you for the input, i will check all these suggestions out.
It sounded like what I had in one model before. There was one infill line that made a turn before connecting to the wall on the other side. Sometimes it didn’t result in spaghetti, but sometimes the spaghetti started from that spot, that’s why it’s always on that layer. Even more weird, the infill lines didn’t always have that problem when resliced. However, by increasing the infill by 5% more, I was able to get the infill lines always connected.
If the bed isn’t hitting the wall, the (heat) bed cord could be pushing on the bed & wall.
Push the bed all the way back & see if it stays there. If it moves forward, that’s your issue. If it doesn’t move…I would still move the desk away from the wall…maybe 6" or so… and try another print.
I don’t have an A1, I have a A1 Mini, SV06, SV06 Plus & an Ender 3 Pro.
All the printers are set with the beds all the way to the back & at least 2" of space so the cord doesn’t hit the wall.
