Starrett 54133 O1 Tool Steel Flat Stock 3/8x8x18 in

Product Description

The STARRETT 54133 is an O1 oil-hardening tool steel flat stock blank used in toolmaking, die making, and precision machining applications. Manufactured to AISI Type O1 specification, this flat stock measures 3/8 inch thick, 8 inches wide, and 18 inches long and weighs 15.3 pounds. Thickness tolerance is held to plus or minus 0.001 inches, and length tolerance is plus 0.250 inches with no negative allowance, giving machinists predictable stock for layout and rough cutting. Tool and die makers, mold makers, and precision machine shops rely on O1 flat stock for its consistent hardening response and excellent dimensional stability after heat treat.

O1 tool steel flat stock is suited for fabricating punches, dies, gauges, cutting tools, and jigs where oil-quench hardening is required. The 8-inch width and 18-inch length provide generous material for single-piece blanks or multiple smaller components cut from one piece. This stock is worked in the annealed condition and hardened by the end user or heat treater after machining to final size.

Key Features

• AISI Type O1 oil-hardening tool steel — consistent hardening response in oil quench
• Thickness tolerance of plus or minus 0.001 inches for reliable fit in precision layouts
• Length tolerance of plus 0.250 inches, minus 0 inches — never undersize on length
• Width tolerance of 0.000 to minus 0.005 inches
• Edge squareness held to 0.003 inches per inch across all edges
• Single-piece packaging with a minimum order quantity of 1

Compatibility

Designed as a general-purpose O1 oil-hardening tool steel flat blank suitable for toolmaking, die work, and precision machining applications requiring AISI Type O1 material specification.

Installation Notes

O1 flat stock is machined in the soft-annealed state using conventional milling, grinding, and drilling equipment. Heat treatment — including hardening and tempering — should be performed by a qualified heat treater following established AISI O1 guidelines. Always allow adequate stock for finish grinding after heat treat to correct any distortion. Handle large flat stock sections with appropriate lifting equipment given the 15.3-pound piece weight.