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Contributor
Adam.Mayes
Posts: 20
Registered: ‎10-15-2012

Meshing assembly

403 Views, 3 Replies
08-01-2013 12:07 PM

Hello,

Anyone have experience with meshing an assembly. The part is a 2 shot overmolding. The Cad model is in Catia. When I import with design link, the mesh is not matched between the 2 components. I have tried with with many settings like "ignore contact/exact match/fault tolerant'. It always tells me that there is an error meshing faces and to check the cad model.

The cad is good when examined in Catia. No overlaps or intersections between the 2 components. Could this be a translation thing from Catia. I have tried importing both .catPart and .catProduct files. Same results

Thanks

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Valued Contributor
nishit78
Posts: 82
Registered: ‎08-05-2009

Re: Meshing assembly

08-27-2013 03:08 AM in reply to: Adam.Mayes

Hi Adam,

 

I too am facing these problems increasingly. Fewer and Fewer of my 2-shot models are meshing when i change the options to "precise match".

 

In my logs i see "First attempt" fail and then it ignores the mesh settings and give me a crappy mesh.

 

I end up trying many cad tricks to see if i can get a matched mesh on interfacing surfaces but usually it does not work.

 

I am still using AMI 2012 and my CAD is Pro/E.

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Contributor
Adam.Mayes
Posts: 20
Registered: ‎10-15-2012

Re: Meshing assembly

08-27-2013 06:21 AM in reply to: nishit78

Hello ni****78.

I sent one of our models to Berndt at autodesk. He examined it and did some repairs with Cad Doctor as it had surface issues that do not show up in Catia. This fixed some issues with the model, allthough in our native Catia there is no issues.

Try meshing with precise match off. Use ignore contact setting. Its my understanding that moldflow will accept a small level of miss match as the solvers have been improved to deal with this. An exact match is hard to get. I am going to purchase Cad Doctor and run all my models through it before meshing.

Adam

 

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Product Support
nordhb
Posts: 463
Registered: ‎03-23-2009

Re: Meshing assembly

08-29-2013 05:34 AM in reply to: Adam.Mayes

Hi,
yes, this is right.
Even if assembly looks fine from cad modeling and no issues of interference or such seen in cad, there can be issues
on underlying surfaces/faces that builds the model/solid.
Those issues comes from modeling operations in cad. Often many of those issues can be healed in CADdoctor.

If geometry issues, the mesher does a fallback tessellation method.
Also if a "merge" of interface surfaces cannot be done, the precise match cannot take place.

Further, solvers has been reviewed to ensure they can deal properly with non matching mesh.
This was to 2012 release, and has been improved since.
The matching between a cavity and part insert mesh, a perfect match is many times hard to accomplish.
Therefore improvements were made in solver to deal with this.
Basically if you run simulation, and no spotty/strange temperature result at interface you should be ok.

Regards,
Berndt



Berndt Nordh
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