Pisa Tower Warping or Config Issue?

I have a generic PA filament and i can’t seem to print this vertical tube without making it bent. Any tips on what is wrong (filament dried on sunlu dryer for days) ?




Have you tried using the Bambu PA Profile as a reference? Have you tried using Bambu filament? The point here is that without a control for experimentation purposes, even if you stumble upon a combination of settings that may conceal defects, you won’t know what the root cause is until you’ve had another filament of like-material to compare to.

There is only one thing from your photos that is unquestionable, you have layer separation. The question remains, why?

If I were to wager, noting the separation, it can be caused by either too low a temp, too high an aux fan, too low a chamber temp. The profile you provided cannot tell us what the environment is like. Was the door left open? Is the printer next to an air conditioning duct that may lower the chamber temp? Are you monitoring the chamber temp with an external thermometer? It is likely a combination of temperature that is contributing to the layer separation. An alternate spool of filament as a reference would help verify this.

Last but not least, even if you dried it out, it may still may contain moisture.

I’m assuming you weighed the filament before and after you dried it to verify the amount of moisture that was removed. That would be the only way to guarantee that the filament has been completely desiccated. Only when the filament stops shedding weight during drying can one be assured that it is in fact totally dry.

It looks as if the layers have been shifted twice, i.e. a slight layer offset has occurred. The print may be interruptedand and the printer cannot find the correct position again. (e.g. this sometimes happens with my X1 when the filament feed gets a bit stuck, then the printer rewinds filament and then resumes printing after the filament has been fed in again).

Another thing would be that the printer has problems with the Z-position, perhaps the print bed is hanging or running sluggishly (filament residue on the threaded rods). The printer would probably indicate a problem with the force sensors on the print bed.

I can’t say anything about warping, a distortion of the image by the camera could cause an illusion. To determine warping, place the printed part with the underside on a flat and smooth surface and press one side of the object with a finger. No light gap should be visible under the object on the opposite side. A second possibility is to place the object with its underside on a flat surface and rotate it, like a spinning top. If it does not rotate or rotates with difficulty, it is hardly warped or not warped at all; if it rotates well, it is warped. But it still seems as if one side has warped upwards and detached from the print plate or the print plate has detached from the print bed.

I would print this with Glue Stick. To make the print object adhere firmly to the print plate, apply a fresh coat of glue before printing the first layer. Maybe it could help to make the first layer a little higher, about 0.24mm. Or also switch off the print bed levelling before printing (if the print bed is basically level) and make the first layer a little higher (I sometimes print without levelling if I have impurities or a lot of glue stick on the plate), you don’t know if the print bed is really level and the automatic levelling reaches its limits.

Best regards!