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Creating rounds as far into the model design as possible

Nose Bleed

New member
I've had several people tell me that I should create rounds as far into the modeling sequence as possible...

Does that mean the rounds should be one ofthe first features I create, or one of the last features?

I've always considered rounds to be cosmetic, so I've left them til my model is pretty much complete - am I doing this backwards? I haven't run across any troubles, but I'm starting to worry now that I'm modeling this stupid alien...

...and does that include spinal bends. I was going to hold off on bending the teeth witha spinal bend until after the model was pretty much complete - should I do the spinal first?
Rounds should be put in last to reduce problems with lost references and lost time spent in feature failure mode.
Bollocks, put them in as you need them.

Just be careful not to make any subsequent features children to them.
I usually just put them in when I need them, but I try to push them toward the end of the model tree.

I don't lose any sleep over it if I put them in at the top of the model tree though.....just keep on top of the references downstream.
In my plastic and casting design practices, I usually put them in towards the end of the tree. Main reason being, they're usually inside/outside radii for molds, that way I could suppress them for any analysis.

Steve C
A good rule of thumb is that rounds, if possible, should not appear in the first half of your model tree.

And you should avoid dimensioning or constraining subsequent features to the edges or tangent edges created by rounds.

When choosing references for your rounds, surf-surf rounds are generally more stable than edge chains.

None of these rules are set in stone; they simply help make your model as stable and robust as possible when changes happen later.

Dave Martin

Torgon Industries
The main reason for putting rounds last on the model tree is to avoid referencing them when defining or dimensioning other geometry. If you have to make them earlier in the model, just put them all on a layer. Then you can suppress all the rounds in the model by layer when adding additional features.