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selective encapsulation?

    
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Paul

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Message 1 of 7

 selective encapsulation?
09-07-2004 12:36 . pm   |   View his/her posts only
I would like to be able to consolidate a series of surfaces into one operation in the history tree. I do not like the idea of encapsulating (as it is) because you lose all the parametrics and sketches that perhaps would need to be changed at a later date. There can be hundreds of surfaces that get used in a typical part of ours, and besides making it difficult to navigate the history tree, typically the history will hang up on surfaces or curves.

I do not like the idea of inserting a component with a bunch of surfaces because the file that you retrieve this from must be saved.

I do not like adding several backups because the file size increases quite a bit, and you still have a large history tree.

I do like the idea of being able to selectively encapsulate a region within the history tree, and if there is not a good solution for what I'd like to do I'd like to submit a PCR.

Any ideas out there?

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ChrisWard2k2

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Message 2 of 7

10-07-2004 09:08 . pm   |   View his/her posts only
Hi

Encapsulation is not the answer because for a large object as you describe, it is all too easy to encapsulate entities that you may later find you need the parametrics for.

Inserting a component is actually quite a good solution - you can build a complex "main" Part Object up as though it were an assembly (a "Pseudo assembly"). Saving is not a problem, the component does not have to come from a seperate file, it can be a seperate Part Object in the same file. Thus, each Part Object that makes-up your main Part Object holds it's share of the definition history. The main Part in turn will have a short and efficient history, largely consisting of component inserts and component merges, so it will regen very quickly.

There is another possibility, and that is to define a collection of entities as a single User Defined feature (new technology recently introduced), but I think a Pseudo assembly is the best solution and should work well for the case you describe.

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Paul

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Message 3 of 7

13-07-2004 10:30 . am   |   View his/her posts only
Thanks for your reply Chris.

Inserting a component would not be a bad option except for the fact that it adds more parts to the object file.

Typically the application that adds surfaces, trims and curves (sometimes in the thousands of operations) is when we try placing an overedge radius between our part's impression and the die. The radius will typically not fall into place, making it necessary to use the intelligent blends and lots of fudging. What this means if you were to insert a component with the overedge radiuses is that you would have to save the file with the history tree that includes part impressions and overedge radiuses, for as many sets of radiuses that you'd like to insert. (Typically this would be 6 sets). Yes the base geometry would be erased only leaving the radiuses, but the history would retain the full record for each set and the file size would be staggering.

I would really like to add dummy geometry to my part with no entanglements.

Perhaps there is or isn't a solution to this but I'd like to discuss this a little bit before I submit a PCR.

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ChrisWard2k2

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Message 4 of 7

13-07-2004 03:40 . pm   |   View his/her posts only
Hi again

I understand your perpose. I think you are may be a little too worried about file size. VX works well with large files and in any case encapsulation isn't going to reduce the file size. What ever the solution, it still takes MB to describe geometry, be it parametric or dumb.

Because of the fillet work you need to undertake, consider a Pseudo assembly approach by splitting the work into logical regions, one region per Part Object. Use the Assembly manager to bring the regions together later to make your finished part. If you need to see other regions whilst editing one of them, they can be temporarily inserted as components - still very light on memory. This technique is especially good because you will not have thousands of operations listed in one big history tree, yet all history can be retained and re-worked later as required in each individual Part Object. The particular method of placing the radiused faces might be speeded up with a macro automation of the task.

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Steve

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Message 5 of 7

14-07-2004 11:29 . am   |   View his/her posts only
I think Chris's method is best. However, in the past I have used an IGES translation to force dumb geometry into a file. Create the blends in a copy of your current file. When you're done, create an IGES file containing the blends and import that file back into your original. (It's best to import into a separate object within your file then merge that object into your working object file.) With this method, you get pure dumb geometry but the history is retianed in the copied file.

Steve

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Paul

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Message 6 of 7

15-07-2004 03:33 . pm   |   View his/her posts only
We've tried IGES before, but sometimes that brings in inperfections. Just like inserting a component you have to hold onto seperate model files.

Someone in our engineering department tried inserting a component of overedge radiuses into a die file that he was working on. It was a mixed bag. The surfaces that he imported that included impression, overedge radius and flashland worked quite well, because they didn't touch the dieface. Conversely the overedge radiuses that touched the dieface added work to the job. If a radius gets imported onto a surface that its supposed to settle against you are very lucky if you finish things without a lot of trimwork.

Perhaps I shouldn't use the term selective encapsulation, but it sure would like to be able to place a lot of surfaces without a long history associated with it. If something had to get changed in the die we would just remove that one operation and build the surfaces over again.

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ChrisWard2k2

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Message 7 of 7

15-07-2004 04:33 . pm   |   View his/her posts only
Hi again

Can you upload a finished file so that I can see exactly what you are doing?
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