Abstract: A device used as an aid in scoring polygonal shapes into glass having a platen rotatable on a base and a compression arm secured to the base, the platen having grid markings and circular markings intersecting the grid markings, and holes at certain of the grid markings into which locating pins, straight edges and clamps can be inserted, the base having a circular recess, the platen being seated into the circular recess, the compression arm being secured to the base and having a glass engaging clamp, the compression arm extending over the platen to secure a piece of glass between the glass engaging clamp and the platen to facilitate a straight line to be manually scored using a hand scoring device, the platen being a held by a retaining force variably applied to hold the platen position by the glass engaging clamp during the scoring operation.