WebDefinitions: Datum Feature – Something you can touch. A surface, cylindrical hole or boss used to establish a datum. Datum – A theoretical representation, a perfect point, axis or plane derived from a true geometric counterpart. Your datum is constructed by … A datum is theoretical exact plane, axis or point location that GD&T or dimensional … For the 2009 standard it means that the datum in question can either be a … Datum Target Lines are frequently represented by using the edge of a … However, as the local size departs from MMC, the form can vary up to the … The virtual condition can be controlled with a functional gauge. Functional gauges … A datum is theoretical exact plane, axis or point location that GD&T or dimensional … WebThe mating surface is designated as the primary datum feature. That much is good. But then the designer chooses one of the small holes to designate as datum feature [B] and another one to designate as datum feature …
HOLE AS PRIMARY DATUM OR NO? - Eng-Tips Forums
WebA hole may be used as a datum feature of size, but this practice has no practical application. False. If a standardized symbol does not exist for a special need, it is a good idea to create one and use it on the drawing. False. Datum features are identified on a drawing by the use of datum feature symboled or datum targets. WebThe simulated Datum Frame (Plane – Orients, Top Hole – Locates, Bottom Hole – Orients) implies the Top Hole has priority over the bottom Hole. Top Hole and Bottom Hole … philippines december 26
Using a hole pattern as a Datum? - PC-DMIS User Forum
WebDec 28, 2024 · This block contains information about the datum element. It may be a center point, a center line or a datum plane depending on the requirement. In the case of concentricity, the datum element is a datum axis derived from a datum feature. Sometimes, concentricity FCF may contain multiple datums. That is the case with shafts with multiple … WebMay 11, 2024 · A center-line CANNOT be a datum. It must be a feature/features. 2x B datum makes sense only if both are holes. When one is a slot, it completely defeats the purpose of having a slot. If the hole is B and the slot is C, the edge can be called out parallel to B-C. Which is the same as the attached drawing's intent. WebDec 11, 2024 · In real situation, a datum simulator can be the base table of a measuring instrument for datum A and the surface of fixturing for other datum. ... for example 60 mm (measured value) > 59 mm (its MMC value), then the axis of the hole can move as much as 0.5 mm due to bonus tolerance. In this case, the bonus tolerance = measured diameter – … trumps sc rally 2023