bbuild

I am having trouble with a UM2. It massively over-extrudes on layers without much area. When printing normally on layers with a bigger area, the feed motor constantly skips backwards, more than once a second. The PLA filament is all the correct cross-section, and I've tried various temperatures. This over-extrusion is causing lots of secondary problems such as clogging of the head which mean that the printer is really unreliable. Is there something I should check/measure on the PCB for the driver for this motor? bbuild

Hi, I designed and have made many of these: http://www.thingiverse.com/thing:108883 unfortunately after upgrading to an UM2 and thus getting round to installing Cura 14, the slicing now fails whereas it was working fine in versions of 13 (at least). Slicing completely misses some internal voids and fills them in (there are supposed to be 10 cubic voids at angles connecting to the five sides of this shape). Is this controllable somehow, or is it likely to be a bug. I have other shapes that I used to be able to make fine, but now no longer work.

I've just started using my Ultimaker, driven by a Mac Mini server running 10.8 latest. Cura is doing strange things. I've done some successful small builds and have been tweaking the settings. Cura has completely locked up twice now whilst running a larger build; unfortunately it was over 90 minutes into the build each time (and only a few minutes before the end both times!). The CPU for Cura went to 100%, the motor still kept moving, but the heater went off so it stopped extruding and caused a right mess as the extruder was still pushing. Cura has not resumed, I just had to kill the process, it was running at 50-100%. In addition, this left an odd "kernel task" running at 50% - perhaps this is some sort of USB buffering? Should I abandon the Mac version of Cura, or is there a known problem? I can run the machine off a PC as well, but its less convenient.