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You may be asking “What is the importance of the padlock?” Well, we need to ensure that the sketch lines are CONSTRAINED to the Reference Planes- ie if a Reference Plane moves, the corresponding Sketch Line moves with it. This will ONLY happen if the two are locked together.

So here’s our finished mass element- it’s not really different from the first one we created. So what’s the advantage of using Reference Planes? Well, let’s say we wanted to add a second mass element as part of the component. We can constrain the second element (via it’s sketch lines) to some of the existing Reference Planes we have previously created

Now changes to the Length Parameter result in a change to both mass elements- which you would expect as they are BOTH constrained to the Reference Plane.

Reference Planes can also be used like “Levels” to form a Level on which to start an extrusion (or other mass / void element). If we switch to an Elevation View, we can form a new “Level” by creating a Reference Plane….

In the image above you can see the original (default) Reference Plane called “Ref Level” with a height of 0. You can also see the new Reference Plane we have just created- I’ve named it “New Base”- remember what we said above: ALWAYS name your Reference Planes!

Now switch back to Plan View. Let’s create a new Solid Extrusion with it’s base on our new “level” ie the extrusion is to start on our Reference Plane “New Base”. I select “Sold Form > Solid Extrusion”. Now before I go any further, I need to set a new Working Plane for the sketch lines. So I select “Set Work Plane”…

Which brings up the Work Plane Control Panel- from here I can select our newly formed Reference Plane…..

Now then! If I hadn’t of named the Reference Plane, how could it appear (named) in this drop-down list?! I know you’re tired of hearing it but “Always name your Reference Planes!”

You know the rest from here- just sketch the base of the extrusion, set a height and select “Finish Sketch”. Of course we could set a parametric dimension (in an elevation view) between the default Reference Plane (“Ref Level” and our own Reference Plane (“New Base”)- this would then give us parametric control over the base height of the extrusion.

Hopefully you’re getting a flavour for the power of Reference Planes when used in conjunction with parameters?

Reference Lines

And now onto Reference Lines. These are not too dissimilar from Reference Planes, but there are some fundamental differences you need to know about. Unlike Planes, Reference lines cannot be named. They are shown as a solid line, whereas Planes are shown dotted...

A typical use of Reference Lines is to form an angular point of reference with which to constrain sketch lines to. You can still use Reference Lines to form “skeletons” for your Sketch Lines- but as you cannot name them, they cannot themselves form Work Planes (ie you cannot use them to form parametric “Levels” on which to work).

Hopefully this article has helped explain the use of Reference Planes and Lines within the Family Editor? If there’s one thing I would like you to take away from this article it is the importance of creating (and TESTING) your parametric skeleton BEFORE you start adding sketch lines, mass elements, etc; to it.