How to manage bends?

How to manage bends?

rhetths
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Message 1 of 29

How to manage bends?

rhetths
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I have a file with a component and i have kept the component's single sketch intact.  When i have finished the design it will be cut out on a cnc router and then folded.

 

My impression is that i could possibly tackle this project two ways, i could design it in final form, and then do a flat pattern for the cnc router.  Or i could design it as a flat plate, and then fold it.  I decided to experiment with the latter approach this time having used the former approach previously.

 

Naturally during the design process i need to fold the plate to see how it shapes up and then unfold it to modify the sketch, or at least i think so?  This has been tedious and time consuming but i have been kinda happy enough.  I had the premonition that i should make sure that i save it when it is unfolded to avoid issues.  Unfortunately i wasn't paying attention and saved it while folded.

 

You would think that should be no drama, any decent program should be able to handle that, but when i reopened the file and unfolded the plate i found i was specifically disallowed to edit the sketch.  Oh dear, thats no good.  I decided to get rid of the design history, and great, i was now able to edit the sketch.  So i invested a fair bit more time refining the design, then tried to refold it.  However, to do that i need to convert it to sheetmetal, and when i try to do that it is now specifically adamant that i can only select part of the component, a sector as defined by lines on the sketch.

 

It seems that no matter which way i try to design sheetmetal components in fusion i end up having to devise workarounds, or is there a solution?  

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Message 2 of 29

TrippyLighting
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please share your design before deleting the timeline.


EESignature

Message 3 of 29

rhetths
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@TrippyLighting wrote:

please share your design before deleting the timeline.


Oh i didn't think of that at that time.

 

There was one 'error' in the timeline, a yellow patch, i imported a complex component and used it like a stamp to create a shape in my main component.  When i extruded the complex component to create the shape in my main component i inadvertently extruded the complex component itself so much that it became non existent, and yet not deleted, it was still listed as a component.  The job was done though, i had the shape i needed in my main component.  I went to delete the complex component because i no longer needed it, but then the design history didn't want me to delete the complex component, and it was at that moment that i realised there was an error in the timeline.  Since i didn't import the sketch of the complex body, i don't know if i even have a sketch of it, or even if i do have a sketch of it if i could import it, and i wasn't confident i could fix the error, i did nothing about it.  Later, after i posted here, with the design history off, i deleted it, and don't see any issues arising out of doing so.

 

I did however come up with a workaround to solve my dilemma, my inability to convert my entire component to sheetmetal and fold it.  I decided to delete the body of my component and recreate it.  Thankfully that didn't take long.  After that i was able to convert all of it to sheetmetal and fold it like a new bought one.

Message 4 of 29

rhetths
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I actually have saved versions with the design history intact, i will see if i can post one here.

 

Well, i thought i had fixed everything, but now i see a new problem.  A different component in the assembly has gone feint.  If i activate it it looks normal, but when the assembly is activated it is feint.  File attached.

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Message 5 of 29

laughingcreek
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Accepted solution

right click on the body and change the opacity to 100%

this is a bug that's been floating around for a while now

Message 6 of 29

laughingcreek
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on a side note,  I don't think the "bend" functionality was intended to be used as a method of design.  It was introduced so that folks who already had a library of flat designs on paper could reproduce the 3d geometry more easily.  I think it is way to mind "bendy" to try and design something new by bending something flat into a shape.

Message 7 of 29

rhetths
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@laughingcreek wrote:

right click on the body and change the opacity to 100%

this is a bug that's been floating around for a while now


Thankyou.  That worked.

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Message 8 of 29

rhetths
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@laughingcreek wrote:

on a side note,  I don't think the "bend" functionality was intended to be used as a method of design.  It was introduced so that folks who already had a library of flat designs on paper could reproduce the 3d geometry more easily.  I think it is way to mind "bendy" to try and design something new by bending something flat into a shape.


It did mean a fair amount of back and forthing.  But the functionality i needed to do it that way is in fusion, the only problem was the brick walls they built in if you save it while folded, which i don't understand.

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Message 9 of 29

rhetths
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@laughingcreek wrote:

on a side note,  I don't think the "bend" functionality was intended to be used as a method of design.  It was introduced so that folks who already had a library of flat designs on paper could reproduce the 3d geometry more easily.  I think it is way to mind "bendy" to try and design something new by bending something flat into a shape.


People have been criticising modelling the body, people have been reiterating the modification of the sketch when designing.  If i designed the component in final form i expect i would have lost control of the sketches, part of my motivation in designing from flat was that i figured i could keep in control of the sketch.  Also, i had to do a workaround in order to manufacture my previous design which i designed in final form.  It made sense to get some experience in designing with both techniques and compare.

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Message 10 of 29

rhetths
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@TrippyLighting wrote:

please share your design before deleting the timeline.


Could this warning be the cause of a brick wall in relation to folding?

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Message 11 of 29

TheCADWhisperer
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@rhetths wrote:

 

Could this warning be the cause of a brick wall in relation to folding?

Has this discussion thread been solved or not?

You normally model sheet metal in finished form.

If you are modeling from flat - you probably have no idea of Bend Allowance or your true final dimensions.

If you get an error you should immediately STOP and ask questions. Do not continue as though somehow it will all automagically come together if you ignore the indicated issue.

Message 12 of 29

TheCADWhisperer
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@rhetths wrote:

1. .... i could design it in final form,

 

  Or

2.  ...i could design it as a flat plate, and then fold it. 


1. Yes, that is the way the Experts do it.

2. No, only the ultra uber experts do it that way, and only as a last resort.  (and beginners who don't realize the implication of Bend Allowance on their final form dimensions.

 

 Now, the techniques you don't mention are 

3. Model in Finished form using Unfold/Refold as needed.

4. Hybrid surface/solid modeling and Convert to Sheet Metal.

Message 13 of 29

rhetths
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@TheCADWhisperer wrote:

@rhetths wrote:

1. .... i could design it in final form,

 

  Or

2.  ...i could design it as a flat plate, and then fold it. 


1. Yes, that is the way the Experts do it.

2. No, only the ultra uber experts do it that way, and only as a last resort.  (and beginners who don't realize the implication of Bend Allowance on their final form dimensions.

 

 Now, the techniques you don't mention are 

3. Model in Finished form using Unfold/Refold as needed.

4. Hybrid surface/solid modeling and Convert to Sheet Metal.


I have seen it written; one sketch, one body, one component.  But in the case of folded components multiple sketches are likely to be required.  How does one ensure all those sketches remain connected to the one body, one component?

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Message 14 of 29

laughingcreek
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@rhetths wrote:...I have seen it written; one sketch, one body, one component.  ...

That idea is only a training crutch for the very beginner.  Has nothing to do with good design practices.

 

Message 15 of 29

TheCADWhisperer
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@rhetths wrote:
1. I have seen it written; one sketch, one body, one …
2. How does one ensure all those sketches remain connected to the one body, one component?

1. Where is this written? Cite your source of (mis)information.

2. P (project geometry).

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Message 16 of 29

laughingcreek
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@TheCADWhisperer wrote:

@rhetths wrote:
1. I have seen it written; one sketch, one body, one …

1. Where is this written? Cite your source of (mis)information.

 


This forum.  There are a coupe of folks who suggest it.  not calling anyone out directly.  but it's usually advice given to beginners struggling to under stand how to operate the software, not advice on how to execute  a good design

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Message 17 of 29

TheCADWhisperer
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@laughingcreek 

I can understand one feature per sketch, but one sketch per body?

That just doesn’t make logical sense to me?

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Message 18 of 29

laughingcreek
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I suspect the OP was conflating 2 separate pieces of advice I've seen here-

-one sketch, one feature

-one body, one component

 

 

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Message 19 of 29

rhetths
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@TheCADWhisperer wrote:

@rhetths wrote:

1. .... i could design it in final form,

 

  Or

2.  ...i could design it as a flat plate, and then fold it. 


1. Yes, that is the way the Experts do it.

2. No, only the ultra uber experts do it that way, and only as a last resort.  (and beginners who don't realize the implication of Bend Allowance on their final form dimensions.

 

 Now, the techniques you don't mention are 

3. Model in Finished form using Unfold/Refold as needed.

4. Hybrid surface/solid modeling and Convert to Sheet Metal.


Okay, so i happen to be back on my previous design, which i have done in final form, making some alterations.  I have a final form bend, and i needed to unfold it in order to create a sketch on it and then extrude the sketch, and then refold it.  So i just got to the point of trying to refold it, and refold is not an option on the menu?  The design history isn't showing any errors.

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Message 20 of 29

rhetths
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Oh wow, i just found refold, it wasn't where i was expecting.  Very exciting.