Quick Guide to Precision Measuring Instruments

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PG08MicrometersHow to Read the ScaleMicrometer with standard scale (graduation: 0.01mm)The thimble scale can be read directly to 0.01mm, as shown above, but may also be estimated to 0.001mm when the lines are nearly coincident because the line thickness is 1/5 of the spacing between them.Micrometer with vernier scale (graduation: 0.001mm)The vernier scale provided above the sleeve index line enables direct readings to be made to within 0.001mm.(1)Sleeve scale reading6.mm(2)Thimble scale reading.21mm(3)Reading from the vernier scale markingand thimble graduation line+ .003mmMicrometer reading6.213mmThese drawings above are for illustration only and are not to scale(1)Sleeve scale reading7.mm(2)Thimble scale reading+ 0.37mmMicrometer reading7.37mm0545403530(1)(2)08604253025201510(1)(2)Approx. +1µmApprox. +2µmThimble scaleIndex lineThimble scaleIndex line08604253025201510(1)(2)(3)08604253025201510(1)(2)(3)Measuring Face DetailMeasuring Force Limiting Devicespindleø6.35ø6.330’spindleø830’ø7.95Carbide tipCarbide tipThird decimal placeSecond decimal placeFirst decimal placeMillimetresTens of mm0299mm64504520Third decimal place on vernier scale ( 0.001 mm units)Vernier reading 0.004mm (2)Fiducial line+Counter reading2.994mm.004mm.09mm.9mm2.mm00.mm*Indicates four digits.(2)(1)(1)Micrometer with mechanical-digit display (digital step: 0.001mm)Note) 0.37 mm (2) is read at the position where the sleeve ducial line is aligned to the thimble graduations.Note) 0.21 mm (2) is read at the position where the index line is between two graduations (21 and 22 in this case). 0.003 mm (3) is read at the position where one of the vernier graduations aligns with one of the thimble graduations.Note) 0.004 mm (2) is read at the position where a vernier graduation line corresponds with one of the thimble graduation lines.Audible in operationOne-handed operationRemarksRatchet stopYesUnsuitableAudible clicking operation causes micro-shocksFriction thimble (F type)NoSuitableSmooth operation without shock or soundRatchet thimble(T type)YesSuitableAudible operation provides conrmation of constant measur-ing forceRatchet thimbleYesSuitableAudible operation provides conrmation of constant measur-ing force