Mitutoyo 293-669-20 Digital Micrometer

Technical Overview

High-speed IP65 digital micrometer with 75-105mm range, ±3 µm accuracy, non-rotating spindle, SPC output, and 10mm/rev feed rate for fast, precise QC.

Key Features

Rapid spindle feed of 10 mm per thimble rotation, delivering 20 times faster adjustment than standard micrometers
IP65 protection rating offers excellent resistance against oil, water, dust, and splashing coolant fluid
Non-rotating spindle prevents torque on delicate workpieces, ensuring repeatable linear contact
ABSOLUTE linear scale maintains origin position throughout the life of the battery, eliminating the need for frequent zero setting
Carbide-tipped measuring faces with micro-lap finish ensure high durability and long-term accuracy
Equipped with a constant-force ratchet stop (5 to 12 N) for uniform, operator-independent measurement pressure
Built-in SPC data output enables integration with external processors and quality control networks (MeasurLink)
Function lock prevents accidental changing of the reference origin point
Large, high-contrast LCD with 10 mm character height ensures comfortable readability

Technical Specification Matrix

Parameter	Value
Measuring Range	75 - 105 mm
Resolution / Digital Step	0.001 mm
Accuracy (Maximum Permissible Error)	±3 µm
IP Protection Level	IP65
Flatness	0.3 µm
Parallelism	3 µm
Measuring Force	5 - 12 N
Spindle Feed Rate	10 mm per revolution
Measuring Spindle Diameter	6.35 mm (non-rotating)
Battery Type	SR44 Silver Oxide Button Cell (1 pc.)
Battery Life	Approx. 5 years under normal use
Physical Weight (kg)	0.59
Dimensions L x W x H (cm)	0 x 0 x 0

Industrial Applications

1. Automotive Crankshaft In-Process Machining Quality Control

Measuring the outside diameter of precision-machined automotive engine crankshafts and stepped drive shafts directly next to CNC lathes where coolant is actively sprayed.

Problem Solved

Standard micrometers are easily degraded by oily coolants and are slow to adjust across step changes. The 293-669-20's IP65 protection prevents coolant ingress, and the 10 mm spindle feed dramatically cuts cycle times when transitioning across different stepped diameters.

IP6510mm spindle feedIn-process metrologyCNC machining

2. High-Throughput Thread and Gear Blank Inspection

Performing rapid dimensional inspections of outer diameters of highly polished cylindrical gear blanks and thread rollers ranging from 75mm to 105mm on the production floor.

Problem Solved

Spindle rotation on standard micrometers can rub and scratch highly finished surfaces. This unit’s non-rotating spindle advances purely linearly, avoiding friction marks on the gear blank, while the SPC output streamlines real-time statistical logging to prevent bottlenecking.

Non-rotating spindleSPC data outputGear blank inspectionHigh-throughput QC

3. Aerospace Pin and Heavy Fastener Compliance Testing

Verifying outer diameters of titanium alloy structural pins and thick aerospace studs requiring tight tolerances (±3 µm) and low operator-dependent measurement variation.

Problem Solved

Inconsistent manual torque applied by operators can result in false out-of-tolerance readings. The built-in 5-12 N constant-force ratchet stop guarantees uniform pressure on the pin, while the 0.3 µm flatness standard ensures reliable micro-level precision.

Constant-force ratchet±3 µm accuracyAerospace pins0.3 µm flatness