Starrett 54520 O1 Tool Steel Flat Stock 1-1/4x1-1/2x36 in

Product Description

The STARRETT 54520 is an O1 oil-hardening tool steel flat stock bar used in toolmaking, die making, and precision machining applications. Manufactured to AISI Type O1 specifications, this flat stock measures 1-1/4 inches thick, 1-1/2 inches wide, and 36 inches long, weighing 19.13 pounds. Thickness tolerance is held to plus or minus 0.001 inches, making it suitable for applications that demand close dimensional control before and after hardening. Licensed machinists, toolmakers, and metalworking shops rely on O1 flat stock as a starting blank for punches, dies, gauges, and cutting tools where oil-quench hardening is the required heat treatment method.

O1 tool steel flat stock sees regular use in job shops and production toolrooms that fabricate custom tooling from raw bar stock. The 36-inch length allows multiple blanks to be cut from a single piece, reducing material waste. The 1-1/4 by 1-1/2 inch cross section suits medium-duty tool and die work. Edge squareness is held to 0.003 inches per inch, supporting accurate layout and machining directly from the bar without additional squaring operations in most setups.

Key Features

• AISI Type O1 oil-hardening tool steel — suitable for heat treatment by oil quench
• Thickness tolerance: plus or minus 0.001 inches for consistent stock removal and fit
• Width tolerance: 0.000 to minus 0.005 inches
• Length tolerance: plus 0.015 inches, minus 0 inches
• Edge squareness: 0.003 inches per inch on all edges
• 19.13 pounds per bar — standard 36-inch length for shop stock

Compatibility

Designed as a standard O1 oil-hardening tool steel flat bar for use as raw stock in toolmaking, die making, and general precision machining applications requiring oil-quench heat treatment.

Installation Notes

Cutting and machining of tool steel flat stock is typically performed by toolmakers or machinists using appropriate metalworking equipment. Carbide or high-speed steel tooling is generally required. Before heat treatment, all machining and grinding should be completed to near-final dimensions, accounting for minor distortion during oil quenching. Follow applicable shop safety practices and local codes when operating heat-treatment equipment.