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Hi guys,
I tried the whole day to print this mod, but my printer (CTC Makerbot Dual clone) begins extruding less filament at this height (check out attached photo) und starts blocking the filament and half clogs the nozzle as it seems.
Any ideas? Printing at 210 degree, 30mm print and travel speed, 1.2mm retraction distance, support activated.
I have the fan mod (http://www.thingiverse.com/thing:537918 ) attached and need to activate it as soon as he starts the overhang, otherwise I get warping.
I'm using sailsfish firmware 7.7 and the Makerbot Desktop 3.10.1 software.
Any ideas?

Active Cooling Fan Duct v2 for Replicator 1 / Duplicator 4 / FlashForge / CTC