Horrible grinding noise and bad print quality at certain position

[stiff talon]

Hi I am having some problem with the printer where printing small models are ok.

However when printing large surface models, there is some grinding noise and subsequently bad print quality at certain location. Please see the videos below and look at the rear or the model. what else can I check?

If the model is placed at the center it appears to be fine. Any ideas?

Small models are so perfect

End result...

[stiff talon]

for those who have problem, it is bed adhesion. Need to use brim for such a large object

[rocky beacon]

Good catch. Brim, higher chamber temps, lower cooling speed are all ways to reduce warping.