Mate Errors

WarningCoincident31This mate is over defining the assembly. Consider deleting some of the over defining mates.



These are the words that are frequenting my computer monitor. If I just delete the mate then undo the delete the error goes away. Right now I'm doing assemblies of crates and just using standard lumber parts. Very simple stuff but if I do 3 or more mates in a row I get this error. Do I need to just not do as many mates in a row or do I need to do them in a certain order to make SW happy? Thanks for any input


Todd

Hello Todd,


With mates you limit the movement of the part. when you make a mate between two parts which are not able to move Solidworks gives you the warning you mentioned.


In the tutorial ( Help menu => Online Tutorial) you find a chapter Assembly Mates. This is a lesson which take you about 30 minutes and explane it better thanI can do.


With kind regards,


Joop

I found it helps if you make a lot of sub assm's rather then just one big assm. If it dont work one way try another.

Hello all !


Todd ! See the mechanical books (or aplly what you are lerning from this books). You must know EXACTLY how many mates you need to constrain any kind of assemblies. I.e. an assembly with a skrew and a hole require one CONCENTRIC mate (between the skrew and the hole) one COINCIDENT mate (between the surface where the hole is and the surface of the skrew head). You can also denied the rotation of the skrew with one more mate. Now, the skrew is FULLY DEFINED (if the hole is fixed in space). If you try to add one more mate for the skrew, SW can't move the skrew where you want and give you the message: "This mate is over defining the assembly".


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Holopro ask, in other post (if I remember ok) about the CONVERT ENTITIES and IN-CONTEXT tools. Holopro ! Think at the same scenario: a skrew and the hole for this skrew. But you have FIRST the screw (a cilinder)and you need to make the hole.


For that, make an assembly with 2 parts. One isa rectangle part with some thickness (a "table")and the other one is a skrew (a cylinder).See the answer for Todd and mate the skrew. Of course youcan not use the CONCENTRIC mate because you do not have the hole yet, so your skrew is not FULLY DEFINED and you can translate it anywhere on the table.


Now, right-click (or simple click - that depend of the versionof SW you use)the "table" and select, from the contextual menu, EDIT PART.


Select a face of the table then apply EXTRUDE-CUT feature. SW switch automaticaly to sketch mode and use the face you select before as the plane for the sketch.


Now you have 2 solution to define the sketch for the hole:


Solution 1 is to CONVERT ENTITIES to make the sketch for the hole(where the entitie wich you convert is the circular edge of the screw). You obtain a circle as the sketch for the hole.


Solution 2 is to work "in-context". Draw a circle on the "table" surface. Select this circle and an circular edge of the screw(both in the same time using CTRL). Now ADD CONDITION for your sketch to be EQUAL and CONCENTRIC with the edge of the skrew.


For both solutions continue: Exit sketch, set parameters for EXTRUDE-CUT feature and click OK, exit from the PART EDIT mode.


You can see that a hole is created and this hole is CONCENTRIC and EQUAL with the edge of the skrew. Move the skrew anywhere on the table then REBUILD the assembly. The hole folow your skrew and is ALL THE TIME concentric and equal with the skrew.


That is all falk . In-context work is the realypower of SW (and other parametrics softwares).


Hope you (both)understand what I say because my english is not as good as I wish.


Good luck !