hello Guys,
i have the folowing issue with my p1s im printing a street model quite a big one and sliced it up into 20 pieces of about 24x23cm but for some reason the very edge of the print gets all messed up but just the top layer the rest is a perfect print. does anyone have any suggetions?
you can see the issue better on these 2 pictures
im using: PLA Matte from Bambu
the attach file is the sliced print with my settings maybe there is something wrong:
01_Gelände A_weiß.3mf (286,5 KB)
Looks like classic edge warping.
A hot layer cools on top of cool layer, shrinks and pulls the edges upwards, reducing subsequent layer heights => Overextrusion.
Initially, it is important to get bed adhesion right. Rigorous plate cleaning is a prerequisite. In addition, bed and nozzle temps for the 1st layer only can be increased by 5° and mouse ears or even brims can help as well. Lower brim gaps will be more effective but also more difficult to remove.
For large prints however, warping is able to lift the print plate off the heat bed. There are edge clamps available on MakerWorld, but I have found it sufficient to address the root cause directly:
Keep the build chamber warm while staying out of the heat creep temp range. Without ironing, I usually target 35-39°C on my X1. For a P1, you can place one of the cheap Hygro-/Thermometers in the build chamber.
Since cooling is very sensitive, I prefer to limit warping by reducing the heat input per layer. That can be done by slowing down and/or reducing the layer height.
and 
heyy thanks that was a good suggestion, but to counter your idea, the printed blocks are completly flat on the bottom there is litterly no singh of warping on the corner or anything else that would suggest the warping theorie. any ohter suggetions
If the plate was lifted off the heat bed, you’ll not see any effects on the underside of the print. Even tiny edge lifts have a big effect as they’ll kill heat flow from the heat bed to the build plate in that area.
But a very slight curvature should indeed be visible. Especially against a really flat surface or edge like a steel ruler illuminated from the back.
There are other possible causes for what looks like flow instabilities though. Most of them come from uneven build chamber temps (typically the aux-fan side, front door gap, poop chute => drafts ) or (hopefully not) a very uneven heat bed temp distribution.
What you could try is to place the print firmly in the centre of the plate (sorry, can’t check your 3mf atm), increase the heat bed temp by 5° throughout, nozzle temp by 10° for the 1st layer only and lower the maximum flow rate of the filament by 20%. If you still have the edge ripples, cut the part in half, hold both parts against each other with the build plate sides facing each other and check for warping.
In terms of root cause assessment, if you have a contactless thermometer you could check the heat bed temp distribution.
