Stack-up Analysis Calculation

[aehernan88]

I am new to stack-up analysis and need some help for a simple calculation. It is for the connection between the two parts shown below. For the coupling those are the only two dimensions that are defined, so we are only concerned about the two corresponding dimensions on the Adapter. Can someone please show me how to perform this calculation?

Thank you in advance.

 

[greenimi]

What is the objective of the stackup? What dimension at the assembly level you are trying to find its limits?

 

[aehernan88]

The objective is to verify that the given dimensions and tolerances allow for a secure connection between the two parts.

 

[greenimi]

What means secure connection? How would you define it in engineering?
As you might know engineers work with numbers. Is zero good enough or interference (minus is acceptable)? How much interference is good? How much slop is needed for assembly?
And most important which is the dimension on the assembly level you think will secure your connection. You design it.
Again, secure connection does not mean anything in engineering. Means probably something in language art, linguistic or in lawyers terminology etc...

 

[Belanger]

A stack needs to have a specific "objective" which needs a specific start/stop point. Something like "I'm looking for the minimum allowable distance between the surface of the hole and the flat on the pin."
We don't know what you mean by a secure connection, so it's better to think about a specific gap or relationship between two verbalized points on the assembly.

 

[aehernan88]

Ok, so I am just looking that there is no interference for the adapter to be inserted into the coupling and that there is any interference between the flat at .100 on the adapter and the corresponding flat in the coupling when inserted deep enough. The depth of that flat in the coupling is not defined but that doesn't need to be considered for this calculation.

Thank you for the help so far.

 

[aehernan88]

Maybe a stackup is not the right thing to do here. Should I just look at the worst case for each individual dimension? For the diameter size and the flat height.