Mahr Multimar M36B-10 / M36B-20 - ID/OD Indicator

The Mahr Multimar M36B-10 and M36B-20 are 2-point "T"-plate bench I.D./O.D. indicator gages designed for fast, accurate comparative measurement of inside and outside diameters, centering edges, narrow shoulders, and recesses in production and inspection environments. Both models share the same precision-engineered gage body, frictionless motion transfer system, and accessory compatibility differing only in frame size and the measurement ranges they cover. The M36B-10 handles O.D. measurements from 6–127mm (0.25"–5.0") and I.D. measurements from 19–140mm (0.75"–5.5"), while the M36B-20 extends that envelope to 6–222mm (0.25"–8.75") O.D. and 19–197mm (0.75"–7.75") I.D., making it one of the widest-range bench comparators available for shop floor diameter inspection.

The defining characteristic of the M36B platform is its frictionless reed-spring pantograph motion transfer system. The pantograph connects the sensitive contact directly to the indicating instrument through a flexure mechanism with no mechanical joints, pivot bearings, or gear interfaces anywhere in the load path. This eliminates the backlash, stick-slip friction, hysteresis, and directional errors that are inherent to conventional lever-and-linkage bench gage designs, and ensures that every displacement of the sensitive contact produces a linearly proportional, repeatable response at the indicator regardless of measurement direction or gaging speed. The parallel spring-loaded measuring force system complements the pantograph by maintaining consistent, adjustable gaging pressure throughout the contact stroke, removing operator influence on contact force from the measurement equation.

In "T"-plate configuration, both reference and sensitive contacts engage the workpiece directly across the diameter, giving a true 2-point diameter reading. A third contact available as an optional accessory can be positioned as a side-stop or centralizer to ensure consistent part location and eliminate positional variability between measurement cycles on the same nominal diameter. This setup is the standard configuration for the vast majority of cylindrical I.D. and O.D. measurement applications, including shafts, bores, bearing journals, ground diameters, and precision turned features where the measurement is taken across a clearly defined diametral axis.

The sensitive contact retracts via dual levers positioned at the front of the gage frame, normally set at 6mm (0.25") retraction depth, adjustable to 10mm (0.40") for measuring grooves, ball races, ring grooves, and recessed features. Reversing the top plate converts the gage from O.D. to I.D. measurement configuration without tools. The gage base tilts and locks at any angle from 0° (fully horizontal) to 90° (fully vertical), enabling both flat-part thickness measurement and upright shaft measurement from the same instrument with no additional support hardware required.

Both models accept any indicating instrument on an 8mm (or 3/8") shank from .0001"/0.002mm dial indicators through Maxµm®III digital indicators with selectable resolution and data output, to Mahr's integrated wireless indicator for cable-free SPC data transmission. The M36B-10 and M36B-20 are also fully compatible with the complete Multimar 844 T interchangeable anvil accessory family shoulder anvils, blade anvils, ball anvils, cylindrical measuring pins, and measuring arm extensions expanding measurement capability beyond plain I.D./O.D. into threads, gear pitch and root diameters, taper diameters, narrow recesses, and other specialized geometries that flat-face contacts cannot address.