[Feature request] : Cosmetic Thread

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chrisb
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Re: [Feature request] : Cosmetic Thread

Post by chrisb »

fcaduser wrote: Sun Jun 14, 2020 3:31 pm I really don't know how FC could manage this.
Have a look at the Fasteners workbench. There is an attribute which can be set to indicate whether the thread should be modeled or not. It's a pity that this value is not expression aware.
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fcaduser
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Re: [Feature request] : Cosmetic Thread

Post by fcaduser »

@chrisb

If the thread is fully modeled with a sweep and cutting process, yes of course in this case there is no problem. This is what I always do for my own parts.

But with a concept of an attribute that would be made with something with no thickness (helical, circle) , used as a purely symbolic representation, then you can't rely on the kernel. That was my point.
cadcam
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Re: [Feature request] : Cosmetic Thread

Post by cadcam »

Please accept these comments as a newbie to FC and therefore I do not know everything that is available or yet to be extracted from the kernel, but some thoughts

As you get larger assemblies trying to support real helical cuts/extrusions can use up CPU power significantly. Thus

1) use cosmetic images - ideally parametric scaled on pitch & length - + colour for material steel,brass, blackened, plated etc

2) Library of screws/bolts/nuts, library/tool for threaded holes with pre-fitted cosmetics

3) Option to globally/selectively switch of cosmetic images in assembly to save recompute/rotation time etc

4) Standard agreed within FC, thus in libraries, as to how to get around potential thread interference when looking for interferences in assemblies. e.g. model external threads with solid to minor diameter + cosmetic at major dia?

- Use linked thread parameters on same axis to check thread dia/length incompatibilities?

5) Potential of minor/major dia + cosmetic to match dimensions shown in TechDraw wb to ASME/BS8888 standard etc. - both engaged and unengaded threads

Please ignore if off topic
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Re: [Feature request] : Cosmetic Thread

Post by pablogil »

+1
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mario52
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Re: [Feature request] : Cosmetic Thread

Post by mario52 »

hi
fcaduser wrote: Sun Jun 14, 2020 3:31 pm I really don't know how FC could manage this. It's not a solid, it's just a sort of attribute. And what would happen if the user decided to make some machining thus altering the thread (a radial hole, two flats, etc) ?
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Re: [Feature request] : Cosmetic Thread

Post by fcaduser »

@mario52

Yes, I know there is zero difficulty to manage an helical curve with its parameters using this kind of tool.

-----------------------

At this stage of the thread, perhaps we should start to formulate a more precise design brief ? Before knowing potential problems, consequences, and the amount of work required.

1) I prefer a helical curve, against the first representation shown in the first post, but do you all agree ? I think it's neat and light.

3) Parameters can be used to constrain screw-nut mechanisms.

2) Actually, the problem only occurs in large assemblies with a lot of threaded parts. I imagine a part containing a thread may be fully modeled or not into its own file ; but if it's true, during the importation mechanism into an assembly, an option should raise "Import the whole thread or substitute a symbolic representation ?"
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