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Snap together parts
Snap together parts  
Hello Aroosh,

I am working on a design that involves parts that snap together (I am not sure if I am using the correct term - by "snap together" I mean fit together like the lid on a Tupperware container).
I want to make something with two parts that can be pushed together so that they fit together and stay semi locked in contact, but can also be pulled apart by sliding them horizontally (as opposed to the vertical pushing together).
I have included a sketch to illustrate in case my clumsy description is too unclear. As you can see, there ia a "male" part and "female" part. My question is this - is there a general rule of thumb when designing parts like this related to how wide the female part should be in relation to the male part? Obviously, if the female part is too narrow, the parts won't fit together, and too wide they won't reliably stay together. The parts are both plastic, but  I am not sure what kind of plastic just yet. Can you give me some advice on how wide to make the highlighted dimension of the female part?
Your guidance would be greatly appreciated!

Best regards,

Hi Eddie

You wont be able to accomplish what you are looking for with the provided design.
It is not clear to me how often these parts need to come apart during a given time, and what is more important to you, coming apart easy or to stay together firmly or both, can they have play or not, these are kind of factors that may affect the design in general, the tolerance will come to play at the end.

good luck

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Aroosh Shahbazian


I`m able to answer to questions regarding CATIA designing software, (detail parts and assemblies), designing tips and methods, able to solve manufacturing problems, creating a long term plan to make any working operation more efficient than it is, cosmos FEA.


I have programmed and have designed auto and aircraft parts for various companies (inside and outside of the United States) since 1990, been working in aerospace industry since 1997 as mechanical engineer and ENG. MGR.

Masters in Mechanical Eng. (solid designing)

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