I have a 3x5 Favia that I want to cut the Dead from the Live parts. There is dead coral on the inside, but Live on the outside and the middle. I don't have a band saw like the Gryphon band saw. I do have a RotoZip Spiral Saw SCS01. Home Depot and Lowe's carries This:
http://www.rotozip.com/en-us/Pages/CategoryDetail.aspx?pid=5041_5039#
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http://www.rotozip.com/en-us/Pages/CategoryDetail.aspx?pid=5041_5039#