hexagon logo
Register Sign in
  • Replies 13 replies
  • Subscribers 222 subscribers
  • Views 182 views
  • Users 0 members are here
Options
Related

GD&T question - Position of that slot

pab39
Hey,

I have to help some engineer for his drawings, and i wonder about something.
Here it is:

Admitting i have that part (picture), and the important thing on it is that the slot has to be well centered related to the Ø15 hole.
As the slot is already dimensionned with profile on the drawing, my fist idea would be to add A reference on the hole, and add A datum into the Profile (picture2)
But would this work ? and is this OK related to ASME ?

Someone proposed to add symetry to locate the slot (pisture3) but i guess this does the exact same thing. and btw, is it possible to dimension symetry related to an axis ?

How would you dimension that ?
Attached Files
Parents
  • Hey, this week i've got some parts so i tried to measure them as defined above.
    But it seems it is a bit more tricky, the results are not the one expected Neutral face
    it seems the datum order also have its importance here.

    As reminder, B is the cylinder where the slot goes into, C is the mid plane of external faces, D is a plane // to C, passing by B.

    For testing, i just took some points on each side of the slot and created SCN1.

    Here are the results:



    I tried to locate the slot only in different ways (B only / BC / CB / D) and also took the distance of each points from the cylinder B.
    I'm not able to say which result is correct !
    The Z distances of points seems good so the results of the form location should be OK.

    Here is what my real part looks like:



    And here is what the analysis shows:



    Questions:

    - Why are the results pos.3 et 4 different ?
    - The point with the largest deviation is 0.025 from the cylinder, i would expect the result of the form position to be 0.050, right ?
    - Why is the analysis showing me some points out of tol while their distances form the cylinder looks OK ?
    - What other dimensionning could i use to locate that slot from that cylinder ?
Reply
  • Hey, this week i've got some parts so i tried to measure them as defined above.
    But it seems it is a bit more tricky, the results are not the one expected Neutral face
    it seems the datum order also have its importance here.

    As reminder, B is the cylinder where the slot goes into, C is the mid plane of external faces, D is a plane // to C, passing by B.

    For testing, i just took some points on each side of the slot and created SCN1.

    Here are the results:



    I tried to locate the slot only in different ways (B only / BC / CB / D) and also took the distance of each points from the cylinder B.
    I'm not able to say which result is correct !
    The Z distances of points seems good so the results of the form location should be OK.

    Here is what my real part looks like:



    And here is what the analysis shows:



    Questions:

    - Why are the results pos.3 et 4 different ?
    - The point with the largest deviation is 0.025 from the cylinder, i would expect the result of the form position to be 0.050, right ?
    - Why is the analysis showing me some points out of tol while their distances form the cylinder looks OK ?
    - What other dimensionning could i use to locate that slot from that cylinder ?
Children
No Data
© 2024 Hexagon AB and/or its subsidiaries. Privacy Policy | Cloud Services Agreement