Hand Threading Taps

A hand threading tap is designed for manual use with a tap wrench and typically has more chamfering and looser tolerances to reduce breakage and make starting threads easier; machine taps are stiffer, have less chamfer, and are intended for power-driven, high-speed tapping

Select a tap based on the thread standard (e.g., UNC, UNF, metric), the nominal bolt diameter and pitch, and whether you need a through or blind hole thread; consult a tap drill chart to pick the correct pilot hole diameter before tapping

Common materials include high-speed steel (HSS) for general use and cobalt HSS for harder alloys; coatings like black oxide, titanium nitride (TiN), or TiCN can improve wear resistance and chip evacuation, with choice depending on workpiece material and cutting conditions

For occasional use, starter sets that include a range of common sizes and possibly a tap wrench are cost-effective and convenient; buy individual taps when you need specific uncommon sizes or higher-quality specialty taps

Keep taps clean and dry, remove chips after each use, lightly oil them before storage, and organize them by size in a protective case to prevent chipping and corrosion

Tap breakage is usually caused by excessive torque, incorrect pilot hole size, lack of lubrication, or poor alignment; avoid breakage by using the correct drill size, applying cutting fluid, backing out frequently to clear chips, and keeping the tap square to the hole

Yes, but choose tap material and geometry accordingly: general HSS taps work well for aluminum and mild steel, while cobalt or specialized stainless taps with sharper cutting edges and appropriate coatings are preferable for harder or gummy materials like stainless steel