Starrett Machinists Level with Ground and Graduated Vial

Starrett 98 Machinist Level, Adjustable Vials, Cast Iron Base
Built for leveling machine tools and inspection setups, this Starrett machinist level pairs ground and graduated main vials with a cast iron base 6.0 in. (152.4 mm) long. In machine shops, tool rooms, maintenance departments, and inspection areas it serves as a compact precision level for bench work and machine ways.
The base carries an involute groove along its entire length, which gives the level a reliable seat on round work as well as flat surfaces. Each vial adjusts to a positive setting and sits inside a satin finished brass tube with a friction-fit closing cover that protects against breakage.

Key features:
• Main vials are ground and graduated, giving a sensitivity of 0.0050 in per 12 in for fine leveling work
• Two horizontal vials on every model support level checks along the length of the base
• Catalog number 98-6 lets you match the exact Starrett 98 model when ordering or replacing

What is a machinist level used for?
A machinist level checks and corrects the levelness of machine tools, fixtures, and workpieces during installation, setup, and inspection work.
Applications: machine tool installation, lathe bed leveling, surface plate setup, fixture alignment, leveling round stock such as shafts, inspection bench checks.
Industries: toolmaking, quality assurance, precision machining, maintenance and repair, metal fabrication.
Users: toolmakers, machinists, quality inspectors, maintenance technicians.

How does a machinist level differ from an ordinary spirit level?
Sensitivity is the difference. A spirit level, or bubble level, reads level from an air bubble that centers inside a liquid-filled vial, and a machinist level works the same way in a precision grade, built to resolve much smaller tilts. This Starrett level belongs in that precision class, intended for machine and toolroom work rather than framing or general construction.

How do you read the graduated vials on a machinist level?
You read the level by letting the bubble settle, then noting where its ends sit against the graduation lines on the main vial. A centered bubble means the surface is level. Because the vials are ground as well as graduated, you can gauge how far out of level a surface sits, not just whether it is off, which is the reading method machinists rely on during machine setup.

How wide is the base on this Starrett machinist level?
The 98-6 base measures 1-3/32 in. wide over its 6.0 in. (152.4 mm) length. That footprint seats steadily on narrow ways and small fixtures while spanning enough surface for larger beds and plates, and it stays compact enough to ride in a toolbox between machine checks.