Struck Tools

What are some safety tips to know when using a struck tool?

Struck tools are made in various shapes and sizes and for many uses and include cold chisels, punches, nail sets, rock and star drills, and wedges. Use the correct tool for the job.

DO

• Wear safety glasses or goggles, or a face shield.
• Use the tools only if they are good condition (i.e., cutting edges are sharp, the struck head has not mushroomed or chipped).
• Hold the chisel, for shearing and chipping, at an angle that permits the bevel of the cutting edge to lie flat against the shearing plane.
• Provide hand protection

• Hand protection can be provided by a sponge rubber shield forced onto the shaft of a chisel or select struck tools that come with hand protectors designed for the tool.
• Punch and chisel holders are also available.
• Discard tools that are bent, cracked or chipped.
• Redress striking tools with burred or mushroomed heads.

• Redress the point or cutting edge to its original shape. Grind to a slightly convex cutting edge. The point angle of the chisel should be 70° for hard metals, 60° for soft.

What should I avoid doing?

• Do not use struck tools if the struck end is chipped or mushroomed.
• Do not use struck tools if the cutting edge is dull or chipped or if the point of a punch is slanted or damaged.
• Do not apply too much pressure to the head when grinding a chisel. The heat generated can remove the temper. Immerse the chisel in cold water periodically when grinding.
• Do not use cold chisels for cutting or splitting stone or concrete.
• Do not use a drift pin punch (also called an aligning punch) as a pin punch intended for driving, removing, or loosening pins, keys, and rivets.
• Do not allow bull point chisels to be hand-held by one employee and struck by another. Use tongs or a chisel holder to guide the chisel so that the holder’s hand will not be injured.

Refer to OSH Answers General Hand Tool Operation for more tips.