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Why can't I create a Mate Connector between geometry in two instances?

StephenGStephenG Member Posts: 309 ✭✭✭
I am trying to understand why it appears not possible to create a Mate Connector between 2 instances within an assembly.

The UI allows geometries to be selected from different instances, but the result is a Mate Connector with the following error: 

I am having a difficult time understanding why this is a limitation. My usage scenario is to create a Mate Connector mid way between two instance to facilitate creating a mate that always positions an instance centered between two instances. 

Right now I cannot even think of a workaround.

Best Answer


  • StephenGStephenG Member Posts: 309 ✭✭✭
    I have exercised my civic duty and voted 
  • steve_shubinsteve_shubin Member Posts: 439 ✭✭✭
    edited March 2020

    YOU SAID — Right now I cannot even think of a workaround

    Here’s a workaround. Takes a little bit of time to do it. But if you want this right now ...


  • mlaflecheCADmlaflecheCAD Onshape Employees, Developers Posts: 118
    edited March 2020
    @StephenG You can insert a "layout" sketch modeled from a part studio in an assembly as a reference to work with.  Fix the sketch in place in the assembly and mate to parts to the sketch.
    Mike LaFleche   @mlaflecheCAD
  • steve_shubinsteve_shubin Member Posts: 439 ✭✭✭
  • StephenGStephenG Member Posts: 309 ✭✭✭
    Very cleaver technique. Impressed.

    Besides creating a tiny dummy part, or a sketch to instance into the assembly, may I suggest using a surface and adding the mate connector in the part studio. (I named the surface "Between MC".)
    (I think a circular disc surface would be a better choice.)

    Using a surface to attach an MC to has the advantage of being able to change its appearance giving it a color and transparency value that makes this slight of hand mate connector stand out in the assembly. 

    Adding the mate connector to the entity in the part studio eliminates the need to create the MC for each occurrence this geometry is used to create (simulate) instances of a MC between instances.

    Comment: Since the UI for creating a MC "Between entities" allows selection from different instances I think this limitation/error is a bug in the software.   
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