What's this problem with my Flashforge Pro? Pls help me

[botio]

Left top corner always is not good.

ABS 220 degree. Test sample file from offical SD card .

Thank you.

my classmates use the same printer and same setting and same file , didn't have this problem.
my classmates use the same printer and same setting and same file , didn't have this problem.

[jfkansas]

Bed leveling is all that is. Be sure to level the bed fully heated or near fully heated at least.

Look at the base layer of the raft, see how it is narrower at the top left in comparison to the rest? That means the top left didn't get smooshed down as much. It just means your build plate is a little low in the back left corner. Other than that it is looking pretty good. I would probably up the temp if it is ABS to about 235. I know it is a preprogrammed file on the card but you can change the filament temp in the menu after starting the print.

[stevendm]

The default "Bed Leveling Wizard" on the front panel just raises the bed without heating it. I didn't realize that it should be heated before calibration / leveling. How does one go about heating the bed for the leveling process?

[jfkansas]

There should be some preheat options. After you start preheating you can back out of that menu and go to leveling. The heating will still continue.

[sasabs]

Just go to preheat on the display. Then go to bed leveling. You don't need the bed heating to continue. In fact you don't want to put your hands on the bed at 230c

[jfkansas]

The bed never gets to 230c. It tops out at 120c, and I never go above 90c even for ABS. Yes 90c is hot and you don't want to stick your hand on it, but you shouldn't have to touch the plate much when using paper for measuring.