Dan,
<< I suppose nobody will remember but did somebody just oil the air
grinder prior to grinding? >>
Do you have any info on contamination issues when using an unfiltered
conventional compressor (oil lubricated) and/or air tools in the
vicinity of composite parts to be bonded?  I have always used oil-less
compressors when working with composites to make sure I wasn't covering
part in an oil mist.  I imagine good filters are an option, but I have
run across folks that thought their little $20 hardware store variety
(with the clear polycarbonate bowl) was sufficient to remove oil from
the air.
Chris Zavatson