Constraint Improvement for added fillets and chamfers

[karthur1]

How many times has it happened to you? You have a part constrained in an assembly, then you (or someone else) adds a fillet or chamfer to an edge, now there are constraint errors when you open the assembly "Relationship with Undefined Geometry".

I get that the edge that was being used is no longer available, but with a mature product like Inventor, it should be able replace that edge with the new one created by the chamfer or fillet.

Thanks

[DRoam]

I like the idea, but which edge should it use? Both a fillet and a chamfer will turn what used to be one edge (shared by two faces) into TWO edges, with one edge sort of belonging to one face and the other edge to the other face. Which face's edge should Inventor use for existing constraints when a fillet or chamfer is created?

Drawings actually seem to do this very well. They seem to very intelligently keep a dimension attached (whether after adding a fillet/chamfer OR deleting one) based on the selections you used to create said dimension. For example, the two pictures below show what happened after I removed the fillet and chamfer from the top corners of the Part and created a new fillet and chamfer on the bottom corners:

You can see Inventor did a great job of re-attaching the dimensions to the right geometry based on the selections I made when creating them.

But how would this translate into the 3D constraint world where the constraint ONLY stores the edge selected, and nothing else which might hint at which new edge to transfer the constraint to?

It would be a very simple matter to re-attach a constraint to a previously-fillet/chamfered edge to the "merged" edge if the fillet/chamfer is deleted. And I agree Inventor should be able to do this.

But the other way around is a little more ambiguous thanks to one edge being replaced by two.

Any thoughts on how to overcome this?

[swalton]

How about an insert constraint that uses a face and a cylindrical bore, instead of just a circular edge?  In that case, Inventor dose not care if the edge of the hole is changed by adding a fillet or chamfer.  2 more mouse picks now vs a broken constraint some time in the future?

I never use Joints, but do they behave better in this case?

[pasi.annila]

Great idea.

In part model history there is a point where the edge has excisted. This edge could be handled as axis (or even 2/3D-sketch) even after its been removed by some feature (ie. fillet or chamfer).

You can do this manually, but it's too work related.

[Anonymous]

This issue catches us out all the time too.

I like the idea of an alternative insert constraint type that uses face & cylindrical bore. Generally, it probably reflects the real intent of the constraint too.