[Print w/ ABS cracked using heated bed]

Joergen,

That was a huge help! Changing the packing density to .96 and setting the fan to run at 25% made a big improvement. Still have a little way to go but those 2 tips were a huge step forward. Thanks

[Print w/ ABS cracked using heated bed]

I've been running it without the fan on at all. Could this also be a source of the problem?

Also, i just ran another test and stopped it due to warping and some abs 'booger' buildup in one spot. See the below photo:

This is on a heated bed, no fan running, running Cura 12.07. Packing density set to .85 and pretty much everything else is default

[Print w/ ABS cracked using heated bed]

Got my heated bed all hooked up this weekend along with my new abs. Was doing some test prints and came along this problem:

 

I linked above to the 39 second point where you'll see a crack develop and start to open up. Any clues as to why this might be happening or how to prevent it?