Engis HS25018 .2756in x 5in 325/400 Grit Diamond Bore Finishing Tool

The Engis HS25018 is a new diamond bore finishing tool (also known as a diamond lap or bore finishing lap) designated SA-T01-0131, with a nominal bore diameter of 0.2756 in (7.00 mm) and an overall length of 5 in, carrying a dual 325/400 grit diamond abrasive for ultra-fine bore finishing and sizing. The tool body is a hollow, slotted spring-steel sleeve with a right-hand helical flute pattern visible in the photos, allowing it to compress radially for consistent abrasive contact against the bore wall — a hallmark of Engis expandable diamond bore finishing tools. At 325/400 grit, this tool is designed for final finishing passes to achieve tight dimensional tolerances and superior surface finish (Ra) in precision bores made of hardened steel, carbide, ceramics, glass, and other hard materials. It is intended for use with Engis-compatible bore finishing machines or drill press/lathe setups with appropriate coolant, and is sold new in the original Engis plastic protective tube packaging as shown.

Product Specifications