Why did my PLA print start warping in middle of the print

The prints did not come off the table, the layer above it just started warping, hows that possible?
please look at the pictures
what should i do?
[postimg.org]
[postimg.org]

Bad layer adhesion? If the top starts warping before the bottom comes off, sounds like your layers aren't anchored together well enough.

My bet would be insufficient cooling of the print. Can't really tell from the pics, but poor cooling leads to the top of the print curling/not setting properly, which will mess up more the further the print goes.

What temp, filament size and layer height? Did you get a close up of the layer that failed? Heated bed?

from what i see, this is my opinion as of today

flow is not consistent. how much cooling does your pla get from cold end? for example is a fan pointed directly at cold end, before pla enters the hot region. this could be gunking up as pla can soften like gummy candy and plug up and not move. how well does your extrude extrude pla, and what is your retraction setting?

bottom line pla does not warp that much , it gets underfeed thru the extruder, and in your case it is not warping, it is adhesion.

why does a layer not stick to previous layers? 1 layer height is not calibrated, flow is not consistent, meaning some layers are likely missing.

so what do i think? i think that flow is not consistent and this is causing perimeters to not be laid down to where there is adhesion to previous layer (because it is not there!)

what to i suggest: slow down infill speed by half, and then if issue still, slow down entire print. fast is only OK if your machine does not wast feed stock.

try only 1 print object at a time for short term

others here have different experiences and one of several people will likely help you out!

Edited 1 time(s). Last edit at 10/01/2014 11:21AM by jamesdanielv.

I've seen that sort of thing happen if a belt slips - it starts printing in midair and everything gets dragged all over the place.