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relations in a part

Uni Phil

New member
I would like to model a cartridge bearing so that I can change the OD, ID, width and have some kind of relation where it fits the appropriote amount of balls in.

I've downloaded the cartidge bearings from this site which say they use relations but have had no luck in both changing any of the relations or understanding how relations are made.

Can anyone explain step by step or point me in the dirrection of a tutorial.

Your help will be much appriciated.


New member
I suppose you know how to convert dimensions to symbols: Feture>modify>dim cosmetics>symbol 2) click on OD dim and call it OD then on ID and call it ID. Now the number of balls for the cartridge diameters you downloaded may be indicated some how. Balls So craete a relation of the number of balls to the OD. Modify value click onthe balls symbol and write a relationship: OD * (number) or whatever the relationship is. Then you create a family table: Family Tab.

I don't think you need to create a relation. Just create a family table!!! with a column for the number of ball.


New member
I think what what you are looking for is using some sort of smart relations with Ifs to determine the number of balls, spacings etc?

Can you take a screen shot of the relations in the model so that we can see it to talk you through this?