Fillets and curves

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idris
Posts: 28
Joined: Wed Jun 30, 2021 4:28 pm

Fillets and curves

Post by idris »

I'm experimenting with fillets and curves.
Sometimes when I create pads from sketches with curves, I can fillet the curved edge where it meets another flat face. Sometimes I get a message "Failed to create" and I can't figure out what conditions need to be met for a curve to be filleted.

Any thoughts?

OS: Windows 10 Version 2009
Word size of OS: 64-bit
Word size of FreeCAD: 64-bit
Version: 0.19.24291 (Git)
Build type: Release
Branch: releases/FreeCAD-0-19
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Python version: 3.8.6+
Qt version: 5.15.2
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drmacro
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Re: Fillets and curves

Post by drmacro »

There are conditions with fillets/chamfers.
  • the fillet radius can't result in consuming an adjacent edge
  • since the fillet process follows edges, it has difficulty when the edge leads to an intersection of 3 or more edges
  • since the fillet process follows edges it is best to make sure any transition from edge to edge or edge to curved edge is tangent
  • fillets between round features will most likly fail (especially a round feature that is tangent to another feature, think the intersection of two pipes of the same radius)
  • Sometimes it is best to set the Refine property of the last feature to true before attempting to fillet
Fillets are highly susceptible to Topological Naming Problem. Thus changes in previous tree features are likely to cause issues with fillets.
Star Trek II: The Wrath of Khan: Spock: "...His pattern indicates two-dimensional thinking."
chrisb
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Re: Fillets and curves

Post by chrisb »

drmacro wrote: Tue Jan 18, 2022 1:02 pm
  • the fillet radius can't result in consuming an adjacent edge
  • since the fillet process follows edges, it has difficulty when the edge leads to an intersection of 3 or more edges
  • since the fillet process follows edges it is best to make sure any transition from edge to edge or edge to curved edge is tangent
  • fillets between round features will most likly fail (especially a round feature that is tangent to another feature, think the intersection of two pipes of the same radius)
  • Sometimes it is best to set the Refine property of the last feature to true before attempting to fillet
Good comprehension. (Point 4 is a possibility to avoid point 2.)
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idris
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Re: Fillets and curves

Post by idris »

Any suggestions on how to fillet the highlighted edges (though not necessarily all with the same radius)?

Image
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Shalmeneser
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Re: Fillets and curves

Post by Shalmeneser »

File ?
drmacro
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Re: Fillets and curves

Post by drmacro »

idris wrote: Wed Jan 19, 2022 10:58 pm Any suggestions on how to fillet the highlighted edges (though not necessarily all with the same radius)?

Image
Did you read my 4th point...this is an example. :lol:
Star Trek II: The Wrath of Khan: Spock: "...His pattern indicates two-dimensional thinking."
idris
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Joined: Wed Jun 30, 2021 4:28 pm

Re: Fillets and curves

Post by idris »

Yes, I read it, and realised this fitted that category.
I was hoping there was a solution :|

Would it be possible to use a Sweep rather than a fillet? My gut says yes, but my head explodes when I try to work out how to do it.
Last edited by idris on Thu Jan 20, 2022 10:10 am, edited 1 time in total.
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hammax
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Re: Fillets and curves

Post by hammax »

... a small dimension difference and refinement may solve the "fillet intolerance" - as drmacro said

Fillet.PNG
Fillet.PNG (16.82 KiB) Viewed 1024 times
Attachments
Fillet_3.FCStd
FC.19.3
(342.29 KiB) Downloaded 9 times
Fillet_2.FCStd
FC.19.3
(59.71 KiB) Downloaded 6 times
Fillet.FCStd
FC.19.3
(44.49 KiB) Downloaded 7 times
domad
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Re: Fillets and curves

Post by domad »

idris wrote: Wed Jan 19, 2022 10:58 pm Any suggestions on how to fillet the highlighted edges (though not necessarily all with the same radius)?
Hi idris, greetings to the Community!
Without the availability of the original file, you can only outline some solutions, four examples of filleting are attached, but I don't know if they are right for you.
Attachments
fitting.FCStd
(948.22 KiB) Downloaded 18 times
examples_filleting.png
examples_filleting.png (197.74 KiB) Viewed 955 times
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