To All:
Coincidentally, I've been thinking recently about making a post about GD&T True Position, but today when cruising through Practical Machinist I noticed that Joe788 made a post that referenced a site that simplifies the explanation of True Position. Here's the site:
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If that one wraps, try this one (it's the same site).
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When getting a Diameter True Position callout, I divide it by two to get the Radial True Position and then multiply that figure by .7071 to get the max amount you can be off in a 45 degree COMBINED X & Y direction.
There are online True Position calculators like the following that can take Maximum or Minimum Material Conditions into consideration.
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