
The Importance of Qualifying Datums
In this Question Line video, Jason explains how datums are qualified and the difference between how CMMs and physical datum simulators set up the datum reference frame for a manufactured part.
In this Question Line video, Jason explains how datums are qualified and the difference between how CMMs and physical datum simulators set up the datum reference frame for a manufactured part.
In this video, Jason shows how to find the zero, or origin, for a given feature control frame. He walks through an example drawing that utilizes a single datum reference frame, describing how the datum reference frame fully constrains the part, noting that more complex parts may utilize multiple datum reference frames, resulting in multiple origin points.
In this Question Line video, Jason explains the difference between locating features using GD&T and doing so with traditional coordinate dimensions. He walks through two example drawings to show when to use GD&T and the benefits of it over traditional coordinate dimensions.
In this Question Line video, Jason compares coaxiality, concentricity, and position as defined by the ISO 1101 standard. The ASME Y14.5 interpretation of concentricity and coaxiality is very different from ISO and is not presented in this video.
In this Question Line video, Jason explains why the 2018 revision of ASME Y14.5 does not permit locating the distance between stepped surfaces with a size dimension. He also explains how utilizing datums and profile eliminates that ambiguous dimension from being applied and how to report that measurement to get the most direct tolerance between the stepped surfaces.
In this Question Line video, Jason answers questions regarding True Position and how to calculate diametric deviations. He discusses the difference between "True Position" and "Position" and walks through the process of determining whether the part passes inspection.
In this Question Line video, Jason reviews how Rule #1 controls the size and form of a feature of size, and what this means for ring gage design and inspection reporting.
In this Question Line video, Jason discusses how datum targets, datum reference frames, and multiple datum structures can be of assistance in casting drawings.
In this Question Line video, Jason walks through a user-submitted symmetric part drawing. He discusses why the drawing is incorrect and how to fix it, noting that the symmetry symbol was removed from the ASME Y14.5 standard due to common misuse of the symbol.
In this Question Line video, Jason answers a question about reverse inspection of orientation and walks through an example to explain why you should not deviate from the inspection criteria given in the feature control frame.
In this Question Line video, Jason discusses manual vs CMM inspection and the reporting requirements of the ASME Y14.45 standard (Measurement Data Reporting standard).
In this Question Line video, Jason discusses reliable datum features. He explains that unreliable datum features can be avoided by following the functional intent of the part and walks through two drawing examples to explain the thought process behind selecting datum features.
In this Question Line video, Brandon walks through examples for both surface straightness and derived median line straightness, explaining how to correctly apply them and discussing design and inspection considerations.
In this Question Line video, Brandon explains the application of derived median plane (DMP) Flatness and discusses its frequent misuse and potential issues when used for stacking parts. He also provides an alternative for controlling flatness for stacking or symmetrical parts.
In this Question Line video, Jason answers questions regarding datum targets and applying flatness and profile of a surface.
In this Question Line video, Jason reviews a drawing example to explain when Maximum Material Condition and Maximum Material Boundary modifiers may be applied.
In this Question Line video, Jason walks through a drawing that includes a position control on a pattern of holes (bolt circle), explaining what the feature control frame is and is not controlling.
In this Question Line video, Jason walks through an assembly drawing to explain the scenario where a feature being controlled by position must have a reference size dimension rather than a tolerance on the size of the feature.