Cleveland C55002 Straight Flute Hand Tap 1-1/4"-12 UNF Bottoming 6 Flutes

Cleveland C55002 Straight Flute Hand Tap

The Cleveland C55002 is a straight flute hand tap designed for cutting internal threads in a 1-1/4 inch diameter with a 12 threads per inch UNF pitch. It suits machinists and maintenance technicians who need to produce precise threads in through holes or deep blind holes. The H4 thread limit targets a class 2B fit for standard assembly requirements. High speed steel construction provides durability for general purpose threading tasks across various materials.

Bottoming chamfer and UNF fine pitch constraints

The bottoming chamfer on this tap is ground to cut threads close to the bottom of a blind hole, but it requires a pre-drilled hole to the correct depth before use. The UNF fine pitch of 12 threads per inch demands a specific drill size of 1.1688 inches to achieve the recommended 75 percent thread engagement. Straight flutes do not evacuate chips automatically, so the operator must reverse the tap frequently to clear swarf and prevent binding or breakage during the threading operation.

High speed steel build and right hand threading

The bright, uncoated high speed steel body resists wear during repeated hand tapping operations while allowing easy visual inspection of the cutting edges. Six flutes distribute cutting load evenly, which helps maintain thread accuracy and surface finish in harder materials. The right hand thread direction follows standard convention for fastening applications. A tap wrench or suitable holder engages the square shank to provide the necessary leverage for manual thread cutting.