Bob Hackett

Been my experience that drilling plastic tends to be "grabby" in much the same way that drilling brass or bronze acts. I`ve had more luck using tools that scrape rather than cut to get the job done. Think of putting a micro bevel on the cutting edge of the hole saw teeth or drill bit that turns the cutting edge into a scraping edge. I`ve found it makes cutting holes in grabby stuff (technical term) much more controllable. Make the modification small enough and you`ll have no problem resharpening back to normal.