I loaded your stl my cad pgm and saved it as stl to see if that cleans it up.
Both version ran to the end in Slic3r 0.9.7
Maybe its your printer settings.
I attached my printer settings in the capture.jpg, the gcode in the zip file and the saved stl file.
good luck
Post's attachmentsCapture.JPG
Capture.JPG 51.76 kb, 2 downloads since 2012-12-04
timer trip.zip 2.28 mb, 7 downloads since 2012-12-04
Trip_Mechanism_with_Plastic_Spring2.stl 1.06 mb, 10 downloads since 2012-12-04
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