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Create Circle with different centre points

foliwe_fossungfoliwe_fossung Member Posts: 4
Hello Every, I have to try to create a sketch of two circles that meets a point.  This is what I did, but it did not solve the issue. The small circle should be 78mm, and the large one should be 116mm 
1. I created the first circle and added some dimension lines
2. I created the second circle using a 3-point circle command, but it will not allow me the dimension of the second circle

I want the  two circles to meet at the point, and I should be able to add dimensions to them


Best Answer

  • MichaelPascoeMichaelPascoe Member Posts: 876 PRO
    edited August 2 Answer ✓
    It appears to be over-defined. Try deleting the dimension of the larger circle.

    Sketches can go red when references are broken as well as when the geometry is over-defined. The smaller circle is already constrained enough so that it can only be one size according to the current constraints. So you must either delete some constraints, or the dimension of one of the circles.

    You can also delete the smaller circle and the construction lines then create a smaller circle with only the constraints you want. For example a regular circle with a tangent constraint to the larger circle. To place a dimension without forcing, place the dimension then press escape instead of enter. This will create a greyed out dimension if it were to over define it. You can make the greyed out dimension the driving dimension by right clicking it and selecting "Change to driving dimension"; note that changing the driving dimension works best when it is changing an already dimensioned geometry, not a fully constrained via constraints only.


Answers

  • MichaelPascoeMichaelPascoe Member Posts: 876 PRO
    edited August 2 Answer ✓
    It appears to be over-defined. Try deleting the dimension of the larger circle.

    Sketches can go red when references are broken as well as when the geometry is over-defined. The smaller circle is already constrained enough so that it can only be one size according to the current constraints. So you must either delete some constraints, or the dimension of one of the circles.

    You can also delete the smaller circle and the construction lines then create a smaller circle with only the constraints you want. For example a regular circle with a tangent constraint to the larger circle. To place a dimension without forcing, place the dimension then press escape instead of enter. This will create a greyed out dimension if it were to over define it. You can make the greyed out dimension the driving dimension by right clicking it and selecting "Change to driving dimension"; note that changing the driving dimension works best when it is changing an already dimensioned geometry, not a fully constrained via constraints only.


  • foliwe_fossungfoliwe_fossung Member Posts: 4
    Thanks for the help, I played around to get it working, but your approach is better
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