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Slot with Basic location and size tolerance but no Positional

Discussion in 'GD&T Standards and Practices - ASME & ISO' started by Mike Martin, Apr 21, 2023.

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  1. Mike Martin

    Mike Martin New Member

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    In the sample image attache is the slot fully constrained in both directions? I get multiple and differing opinions depending on whether we talk about the vertical or horizontal direction. (Datum A is not shown but is the large flat mutually perpendicular face). If it is what are the extremes of geometry that it allows?

    Please excuse my use of powerpoint as CAD software!
     

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    Mike Martin, Apr 21, 2023
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  2. Miner

    Miner Moderator Staff Member

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    The Position feature control frame does not have the diameter symbol in front of the tolerance. Also, the feature control frame is shown next to the long slot dimension rather than the feature itself. This means that the tolerance only applies to the long axis of the slot. The short axis of the slot appears to be missing a similar position callout. See the example below.

    [​IMG]
     
    Miner, Apr 21, 2023
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  3. Mike Martin

    Mike Martin New Member

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    Thanks Miner.

    Your evaluation is correct. The positional control is intended to only provide control in the direction of the 40.2 dimension. There (perhaps intentionally) is no additional positional control in the 24 direction. With only the controls given can the allowable bounds of the slot be determined? I'm not trying to correct the print, I am trying to interpret the one I've been given and decide if it really does fully define the geometry. If it does I want to understand it. It if truly does not then I will need to go to battle with a tough customer.
     
    Mike Martin, Apr 21, 2023
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  4. Miner

    Miner Moderator Staff Member

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    No. The dimensions in that direction are all basic dimensions, which means that they need a positional tolerance to provide any latitude.
     
    Miner, Apr 21, 2023
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