Repl2x: second extruder picking up raft

[AaplMike]

Hey all.

I have a Replicator 2x and I'm trying to print using a raft. What I'm seeing is that as the first layer of the raft is being laid down, the second extruder usually catches a high spot and rips up the raft from the print bed, ruining the print.

What do I need to do to avoid that?

Bed: 110° with kapton tape
Extruding ABS @ 230° on right extruder
Left extruder left off

I recently calibrated the bed using a business card for height.

Thanks.

[Print Plastic]

1. check bed level first.
Then do step 2.
2. make sure the nozzles are the same height or no more than .002" difference.
Here is a link to the instructions.
http://support.makerbot.com/troubleshooting/makerbot-replicator-2x/mechanical/my-extruder-nozzles-are-at-different-heights_11422