文档介绍：Angular uracyof5'(minutes)ofadegreeusingauniversalbevelprotractorMakeangularmeasurementstolessthan5'ofadegreeusingasinebar,gageblocks,montoolsUniversalbevelprotractorSinebarSineplate3Precisionanglestowithin5'(º)ConsistofbaseVernierscaleProtractordialSlidingbladeDialclampnutCopyright©TheMcGraw-panies,(90º-180º)Acute-angleattachmentfastenedto protractortomeasureangleslessthan90ºMainscaledividedinto twoarcsof180ºScaledividedinto12 spacesoneachsideof0Ifzeroonvernierscale coincideswithlineon main:readingindegreesCopyright©TheMcGraw-panies,Inc. ©TheMcGraw-panies,,notewhichvernierlinecoincideswithmailscaleline50ºFourthMultiplynumberby5'andaddtodegreesonprotractordial4x5'=20'Reading=50º20'uracyofanglemustbecheckedtolessthanConsistsofsteelbarwithtwocylindersofequaldiameterfastenednearendsCentersofcylindersexactly90º.±.0002 or10in.±.. in5inches8SineBarsHypotenuseofaright-ºbuildup=5(sin30º)=5(.5000)=:Thisformulaappliedonlytoanglesupto60º.10