External copy geom

Working on part [a] point is reached when a surface is required for use in part [b], so publish geom in [a] and external copy geom in [b]. Now if further work is done in [a], say the surface is punctured or trimmed beyond the point it was published then this new shape appears in [b] when its regenerated. Beats me how something that is published at a particular point knows of further work being done to it. I workaround this by copy surface before publishing, this locks the shape at the desired point. But how does the published geometry reference something after it was created?

Thanks

Reply to
kenny
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No idea. If you don't want your referenced geometry to update, then make it read only.

As it seems the surface you are using becomes reference data for several parts, it really should be in a skeleton, so it can be referenced by both parts.

Reply to
John Wade

Your fix (workaround) was the correct way to do it, you save/freeze/copy that point in time/history. Otherwise, as history or the external topology changes, you may loose the reference you once had.

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Reply to
Paul Salvador

This is a puzzler. I'm trying to do as you've suggested, see if I can (in classic helpdesk fashion) "reproduce the error". So, in part A I create a publish geom of some seed/boundary surfaces (even going so far as to reorder a hole to see if the PG feature would update, it isn't affected by reordering he hole before the PG feature), then in part B, create a feature with 'Insert>Advanced>Copy Geom' and leave the Publish Geom icon active (WF3). I click in the Pub Geom collector open file box, pick my model with the Pub Geom feature and pick it. Original PG feature copied into part B. Go back to part A and add another hole, after PG feature, to see if it's affected. It is NOT affected in part B. Perhaps you've rolled Insert mode up before the PG feature, altered the original geometry and resumed/cancelled insert mode which could conceivably alter the PG feature? I think I can say, with some certainty, that later features don't alter the PG feature. Something else is going on!

David Janes

Reply to
David Janes

"David Janes" wrote in message news:ff1Ih.12683$ snipped-for-privacy@newsfe12.phx... > "kenny" wrote > Working on part [a] point is reached when a surface is required for use > in part [b], so publish geom in [a] and external copy geom in [b]. Now > if further work is done in [a], say the surface is punctured or trimmed > beyond the point it was published then this new shape appears in [b] > when its regenerated. Beats me how something that is published at a > particular point knows of further work being done to it. I workaround > this by copy surface before publishing, this locks the shape at the > desired point. But how does the published geometry reference something > after it was created? >

This is a puzzler. I'm trying to do as you've suggested, see if I can (in classic helpdesk fashion) "reproduce the error". So, in part A I create a publish geom of some seed/boundary surfaces (even going so far as to reorder a hole to see if the PG feature would update, it isn't affected by reordering he hole before the PG feature), then in part B, create a feature with 'Insert>Advanced>Copy Geom' and leave the Publish Geom icon active (WF3). I click in the Pub Geom collector open file box, pick my model with the Pub Geom feature and pick it. Original PG feature copied into part B. Go back to part A and add another hole, after PG feature, to see if it's affected. It is NOT affected in part B. Perhaps you've rolled Insert mode up before the PG feature, altered the original geometry and resumed/cancelled insert mode which could conceivably alter the PG feature? I think I can say, with some certainty, that later features don't alter the PG feature. Something else is going on! BTW, anyone know anything about INHERITANCE features? Do they fit in here somehow? What's the difference between Copy Geom, Pub Geom and Inheritance Features? Their capabilites and applications? These elude me.

David Janes

Reply to
David Janes

Hmm, I have not honestly used publish enough or WF3 to see this but it maybe a rollback issue as you have noted but it maybe how the feature, topology, boundary is referencing? Without seeing how the data is being used/referenced, we can only speculate.

Anyhow, I'll give it a go with the other question... External Copy Geometry = "in process" core modeling intent (prototype/preproduction). Publish = "released/prerelease" shared data with other modeling groups (preproduction, minor changes). Inheritance = "released or final" data to other groups or manufacturing (production, using final data (purchased parts))

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Reply to
Paul Salvador

Hello anyone, there are some (expensive) knowledges about inheritances:

  1. Inheritance = COMPLETE PART TREE in your part INHERITED.
  2. Extremely simple for use - you can modify the features in inheritance similar as flexible parts in assembly. Solid geometry, datums, parameters and variables from all inherited features are dynamically and FLEXIBLE - simply click on tree of inherited part and modify. Example: New Part->Inherited casting part reference->Machining features only
  3. You can combine more different inherited part in two or more parts all at once in an assembly (but then you regenerate in every inheritance the complete referenced part).
  4. Exteremely unstable, if do you make BOTTOM->UP inherited build in TOP->DOWN metodology. Only modify everything in tree or parameters in more parents (make inherited references in more levels, every level has a associated value parameter, which serves for TOP->DOWN control of assembled inheritances). ATTENTION - without reported circular references (PTC mistake) in log and with high risk for stability.
  5. It is very hard to identify origin of inherited geometry in complicated higher level part - you can find INHERITANCE only, original feature is not reported - in Pick-List, in Find dialog and in Layers too only INHERITANCE FEATURE.
  6. The recommended PTC-technique is TOP->DOWN with PUBLISH GEOMETRY. Our test with two identical assemblies (about 40 Parts in 3 levels): Inheritance Bottom->Up: 2 minutes, every time with yellow warning light PTC reccomended Publish Geometry Technique Top->Down: 20 seconds, green light

General Conclusions: Dear PTC Cookeater, use easy and simple external inheritance and then regenerate, REGENERATE, R-E-G-E-N-E-R-A-T-E or build smart top->down copy geometry design.

Difference Publish Geometry (PG) and Copy Geometry (CG) in TOP-DOWN:

- CG is link to geometry of specific entity (not set) only - you need more CG's for complex geometry reference

- PG is link to preliminary prepared (published) set of geometry - you don't need more CG's to make complex geometry references. Example: Assembly skeleton defines the frame beams. Every beam needs only one skeleton reference - you work with CG only. For fabric cover references you need more beams - you prepare for cover in skeleton PG feature and then simply reference only this one - without CG separated in more CG features.

KL P.S. Sorry for my "basic" english

Reply to
karel.lang

Hey Karel,

Thanks for that, very interesting!

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Reply to
Paul Salvador

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