I've got a 3DR printer, with your e3d hot end, 1.75, .35 orifice, PLA running at 190 (and some Makerbot filament I've run at 230...and some ABS I've run at 245 with a cold bed and warpage) I've got the fan running constant on, and another fan running on the Bowden to keep it cool, but I can't seem to get any print that runs longer than 45 minutes or so. When I pull the filament and snip off a little bit of the end, it extrudes well again. 190 seems a little cold as it extrudes MUCH easier at 200-205, but either leads to an eventual plug. Suggestions? This thing is _SO_ close to being dialed in it's driving me nuts!