Mating Parts in Assemblies

[ANDYDABICO]

Just how important are mates in an assembly, i ask this question because more often than not i end up using then deleting mates during the assembly stage to get the assembly together. Should i perservere and use the correct mates to join components or does it not matter as long as the parts go together.

 

[MMike1]

Uh.... you delete all of your mates? How do your assy's stay together?

You do know that if you try to drag your parts, they WILL move if they are not constrained, right?

In short, mates are VERY important!

 

[MadMango]

Mates are very important, and are a key to a fully parametric (associated) assembly.

Without Mates, if you were to move a hole in one part, there would be no telling how a mating part would be affected by that change.

Without Mates, if you changed teh size (width, length) of a part, there would be no telling how surrounding parts would be affected by that change.

Some common mistakes I see with some new users is they think Mates are only good for the "design" stage of a project. These types of people often replace Mates with "fixed" parts. This causes a lot of trouble and problems later down the road. I always train people (at work) to never Fix anything.

When Mating, you do not need to go overboard, meaning you don't always have to keep adding Mates until your parts are fully constrained. An exampleof allowing unconstrained parts in an assembly would be a srew in a hole. You'd want to use a Concentric Mate to place it in the hole and perhaps a Coincident Mate to define the depth of install in the hole. Do you really need to add a 3rd Mate to stop it from rotating in the hole? Probably not.

Another key tips are to always Mate Planes together if possible. This will ensure a more robust final assembly model.

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[ANDYDABICO]

I have fallen into the 'Fix part' trap (thanks MadMango), once my parts are together in an assebley, my parts stay together that way, my assemblies arnt very compicated therefore i havnt come across any problems, but i see your point (MMike1), i will concentrate more on getting the mates right in the first place.

Thanks