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Tool - Concrete Diamond Saw Blade

DEWALT DW4712B 7-Inch High Performance Diamond Masonry Blade

Diamond Saw 7in Blade 

http://www.amazon.com/gp/product/B00291EJ32/ref=oh_aui_detailpage_o00_s00?ie=UTF8&psc=1     $11.07

You can use this in a regular circular hand saw.  It is best to have someone point a garden hose at the cut to keep it wet to keep it cool and avoid dust.  Use a GFCI power outlet to power the saw if you are using water.  Use safety glasses, ear protectors, and a dust mask.