How to set up a Family of Parts

Here’s a little tutorial on how to create a family of parts from an initial part. First, you have to make sure that all of your dimensions are driving dimensions. In Solid Edge, driving dimensions are called “locked” and are usually signified with a lock symbol, and are red in color. Green dimensions are selected, but the Length dim is driving. Blue dimensions are unlocked, or driven. Before proceding, I had to fix the “headdia” dimension.

I’m starting from this model of a screw which I made myself, and I did it as a synchronous model. Your parent part, or what they call the master part in Solid Edge can be either Ordered or Synchronous. The resulting part will always be ordered, however. There is a reason for that, and I’ll get into that later.

Anyway, the ability to show all dimension names instead of values is available from a right click on the dimensions in the Pathfinder. Pretty cool. To name the dimensions, I just selected them in the Pathfinder and pressed F2. Seeing all the dimensions listed in the tree is pretty cool, because you can group them however you like, and turn them on or off as individual dimensions or as groups very easily.

There are two ways to create the Family of Parts in Solid Edge. One is by using the Family of Parts Edge Bar, and the other is by using a table. I’m going to use the table.

If the PMI dimensions are not red – locked, you will not be able to use them to create Family of Parts. Like an idiot, I struggled with this for about 45 minutes before realizing that I could not drive blue dimensions with a table.

Next I wanted to make sure that the change directions on all of the dimensions were set up correctly. Just as a reminder, the red arrow at the bottom of the Length dimension indicates which side of the dimension will change. In Works, you have to establish this with sketch relations, which you will find is very clunky when you’ve used this method a couple of times.

Anyway, I want the length to change at the bottom, the head height to change at the top and the socket depth to change at the bottom. Socket size was set up as a linear dimension, and I want that to change symmetrically. head and body diameters can only change one way – such that the center stays stationary, so those do not require adjustment.

Next I make sure I have access to the Family of Parts interface, so from the View tab, on the Show group, I use the Panes flyout to select the FOP. With FOP you can control Live Rules, and Relationships, but we’re not going to worry about either of these things now.

The Variables are essentially the dimension names. I haven’t added any to the list yet.

The tool to access the table is the one on the right of the top most row of icons. The table is shown below.

The default values belong to the master part, and don’t really effect the family. The first member of the family is labeled 10-32×1. This is just like the configuration name in Works. From here it’s easy to copy columns and change values. Notice that each FOP member also gets its own file.

In one of the previous posts, some Edge users mentioned that they preferred to use files divorced from the family, which is also possible. You can create them this way, and then break the links. The way the family works is just like how Configurations work in Works, except that the data is all stored in individual files. In the child parts (the family members), the master part shows up as an inserted part. This is why the child has to be ordered. You cannot make synchronous changes as features on top of an existing part. That’s an ordered workflow. In the end, it’s not really a limitation. Any changes you want to make can be made as part of the FOP edits, which can be handled as synchronous. And really, parts like this aren’t going to get changed that way that often anyway.

So for those of you who are curious, the file size for this part is 272 kb. It doesn’t have any chamfers or fillets. Any size created by this master should have approximately the same file size. The Parasolid saved out from this file is 16 kb. The reimported Parasolid has 208 kb. Rick, care to comment on that?