http://www.todaysmachiningworld.com/forum/topic/termanology-definition-concentricity-vs-run-out-vs-position-requirement Brought to you by Todays Machining World en-US Thu, 09 Feb 2012 03:23:34 +0000 http://bbpress.org/?v=1.0.2 q http://www.todaysmachiningworld.com/forum/search.php http://www.todaysmachiningworld.com/forum/topic/termanology-definition-concentricity-vs-run-out-vs-position-requirement#post-106 Fri, 13 Feb 2009 20:40:52 +0000 Anonymous 106@http://www.todaysmachiningworld.com/forum/ <p>Runout tolerances (circular runout and total runout) control the form, orientation and position of individual features - datum axis required.- Circular runout is a two dimensional, surface to an axis contol.- Total runout is a three dimensional, surface to an axis control.<br /> Concentricity tolerances control the location of opposing median points of a feature (datum axis or median plane required)- Concentricity is a three dimensional tolerance.<br /> Position for coaxial features is a three dimensional, axis to axis control.<br /> I suggest you refer to ASME Y14.5M-1994 <a href="http://catalog.asme.org/Codes/PrintBook/Y145M_1994_Dimensioning.cfm" rel="nofollow">http://catalog.asme.org/Codes/PrintBook/Y145M_1994_Dimensioning.cfm</a><br /> Understanding the differences in these specifications will allow you to assure compliance. </p> http://www.todaysmachiningworld.com/forum/topic/termanology-definition-concentricity-vs-run-out-vs-position-requirement#post-90 Fri, 13 Feb 2009 16:07:55 +0000 Anonymous 90@http://www.todaysmachiningworld.com/forum/ <p>We are a job shop manufacturing turned parts on screw machines and CNC lathes for a variety of customers and industries.</p> <p>On parts with multiple diameters some customers call out a concentricity specification. Others will use run-out and some show a position requirement. Aren’t they really all asking for the same thing? Why do they say it three ways, and can they be used interchangeably? </p>