Starrett 52680 Steel Rule 18 in 4R Graduation Rigid

Product Description

The STARRETT 52680 is an 18-inch rigid steel rule designed for precise linear measurement in trade and industrial applications. Manufactured from spring steel with a satin chrome-plated finish, it delivers clean readability and corrosion resistance under shop conditions. The rule carries 4R graduation, meaning four scales are present: 1/16, 1/32, 1/64, and 1/8 inch. At 1-1/8 inches wide and 0.050 inches thick, it lays flat and reads clearly without flexing. Machinists, pipefitters, sheet-metal workers, and fabricators reach for this rule when they need consistent, repeatable measurements on the bench or in the field.

The 52680 suits general layout and inspection work in fabrication shops, mechanical rooms, plumbing rough-in, and HVAC duct work. Its rigid construction keeps the blade from bowing across longer spans, which matters when scribing lines or checking material dimensions. The horizontal scale orientation and silver satin-chrome surface reduce glare under artificial lighting, making graduation marks easy to read in low-light service environments. It is sold individually and requires no accessories for standard use.

Key Features

• 4R graduation: four scales in one rule (1/16, 1/32, 1/64, and 1/8 inch)
• Rigid spring steel construction resists flexing across the full 18-inch length
• Satin chrome-plated finish reduces glare and improves graduation contrast
• 1-1/8-inch width provides a stable lay-flat surface for scribing and layout
• 0.050-inch blade thickness balances durability with compact profile
• Non-magnetic, no hook included — straightforward layout tool

Compatibility

Designed as a standard rigid steel rule suitable for general-purpose measurement and layout tasks across machining, fabrication, plumbing, HVAC, and electrical trade work.

Installation Notes

No installation is required for this measuring tool. Store flat to prevent warping and avoid contact with abrasive surfaces that could wear graduation markings. Clean with a dry or lightly oiled cloth to maintain the chrome finish and prevent surface rust in humid environments. Do not use this rule as a cutting guide with rotary tools, as edge damage will compromise measurement accuracy.