cancel
Showing results for 
Search instead for 
Did you mean: 
cancel
Showing results for 
Search instead for 
Did you mean: 

Community Tip - Learn all about PTC Community Badges. Engage with PTC and see how many you can earn! X

Break direct external reference.

rda
4-Participant
4-Participant

Break direct external reference.

Hello. I have a question about breaking reference.

I have an assembly whit two part. The first part has one hole. I created a hole on the other part by creating a point (with a sketch) in the center of the hole of the first part. Now iI want to break the reference, but this situation is different from copy geometry. If I go to the sketch with external reference I can't see any option about breaking reference.

Also the reference viewer doesn't give me possibility to break relation.

Thanks

5 REPLIES 5
Pettersson
13-Aquamarine
(To:rda)

Short answer: Don't do that. Using external references as sketcher references is inviting disaster. If you want to use an external reference, use Copy Geometry.

 

However, it can be practical to do it temporarily and then remove the reference, which is probably what you're trying to do here. But the only way to remove it is to go into the sketch and into the References window and delete or replace the reference.

Tdaugherty
16-Pearl
(To:rda)

Hi, 

 

If you want the ability to break feature references on demand, you need to set the following config option:

 

feat_references_to_backup other_models

 

This setting tells Creo to backup feature references from other models. In your case, the reference for the sketch would be backed up into the part you are trying to create the hole in. You can control the dependency with the update control options in the geometry backup, just like a copy geometry. The geometry backup feature will be stored inside the feature that is using the external reference.

 

Tdaugherty_0-1596804803397.png

 

The reference viewer will not allow you to break references. If you aren't using geometry backups, you will have to break the external reference manually.

 

Finally, although many people on these forums avoid external references and recommend against them, they really aren't as bad as people make them out to be. If managed well, they can make the design process much more efficient. We design with top-down techniques and tons of external references. Pretty much everything is designed to flex and grow as other things change. The key is to manage the relationships in a logical way and create breakpoints where reference sharing stops. 

 

Ty

 

StephenW
23-Emerald II
(To:Tdaugherty)

What are the downsides (or implications) to using this option? (feat_references_to_backup other_models)

Hi Steve, 

 

I can't claim to have done extensive testing with this setting. I did have a group of users (probably 30) testing it for a while and I didn't hear any complaints. I've used it personally as well and I didn't find any functional issues. I do get a little annoyed with the extra features in the model tree and extra information in the parts. The backed up geometry is visible.

 

Maybe a little hard to see, but the backed up axis pattern is shown in addition to the internal axis in the holes.

Tdaugherty_0-1596807673063.png

 

I have not tested to see if the geometry backups increase file size or impact performance. 

 

If you aren't using a lot of external references, you won't have to deal with so many geometry backups. Like I said before, we use a ton of external references (that don't get broken), so we end up with tons of backups. I think the backups are pretty cool and can offer a lot if used properly. We just don't use them at the moment. 

 

Ty

Pettersson
13-Aquamarine
(To:Tdaugherty)


Finally, although many people on these forums avoid external references and recommend against them, they really aren't as bad as people make them out to be. If managed well, they can make the design process much more efficient. We design with top-down techniques and tons of external references. Pretty much everything is designed to flex and grow as other things change. The key is to manage the relationships in a logical way and create breakpoints where reference sharing stops. 

 


I like using external references, but I try to keep a strict hygiene when possible. Use a skeleton, publish geometry and copy geometry. Only copy geometry "down" into the structure, never "up". I do sometimes deviate from this, but wherever possible, I try to keep this structure, as it gives me a clear overview and good control, and avoids circular references. I especially like using publish geometry, as it signals to whoever is using a part that this geometry is used elsewhere. Decreases the risk of regeneration issues.

Top Tags