mating is better than fixing

The title kind of sounds like it could be the headline of a relationship article but this post is actually going to be about fully constraining your model in an assembly.  When inserting parts inside of an assembly it is really easy to fix the part and continue on.  This allows you to fully constrain a part so that it doesn’t move and it is extremely quick and easy.  However, as easy as it is I am a major opponent to the practice of mating because it is easy to quickly float that part, move it a very little amount and fix it again and no one would ever know.  That is until the part gets made and stuff comes out wrong.

As is with most things in SolidWorks there is an alternative way to quickly fully constrain a part with only a few quick clicks.  When you insert a part into an assembly you can mate the origins of the part with a coincident mate and select “Align axes”.  How you may ask, where here you go.

To start simply insert a part into an assembly.  Select the origin of the part you just inserted and the origin that you would like it mated to.  In the picture below you will see that I want to mate the origin of the part I inserted to the origin of the assembly.  After you select the 2 origins select the mate command to begin the process.

Automatically when you do this SolidWorks will select the Coincident mate as your choice, which is correct.  Here is where you will notice one difference from what you would normally see with the coincident mate.  Underneath this mate you will see a check box for the ability to Align axes.  This is automatically selected for you.  If you would wish to be able to rotate around the axis you would want to uncheck this option but for what we are trying to accomplish you will want to leave it checked.

Now all you have left to do is accept the mate and your part is now fully constrained inside the assembly as shown below.

Now this option might not always work for you but with a little thought into what you are hoping to accomplish in your assembly when making the part you may be able to incorporate a little design intent so that you are able to use it.

Well, there you have it.  Another alternative to a SolidWorks process that is a little safer than just fixing the part wherever it may land in the assembly.  I personally still like to mate all 3 planes of my part file to something in the assembly but that is just a personal preference.  How do you fully constrain the parts in your assemblies?  Let me know!