Chamfer is driving me nuts :-)

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NHSA_Rainer
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Chamfer is driving me nuts :-)

Post by NHSA_Rainer »

Hi,

I am making some timing gears and everything goes well until I want to apply a 0.25mm chamfer to the slot of the thick part of the gear.

Why is FreeCAD not accepting to do it ? I have redrawn several times this piece and still no luck.

Thanks Rainer

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chrisb
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Re: Chamfer is driving me nuts :-)

Post by chrisb »

Chamfers (and fillets) are sometimes a bit picky. This comes from the third party kernel, the FreeCAD developers cannot fix it.

Here you can apply the chamfer as soon as possible, i.e. directly behind Pocket.
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Shalmeneser
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Re: Chamfer is driving me nuts :-)

Post by Shalmeneser »

1) Fillet the 4 lines inside the slot hole. (r=0.01 mm)
2) Chamfer one side of the slop opening.

Imho, chamfer doesn't like the non-tangent border of the slot opening.
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Capture d’écran 2022-08-11 024030.jpg
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chrisb
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Re: Chamfer is driving me nuts :-)

Post by chrisb »

Shalmeneser wrote: Thu Aug 11, 2022 12:43 am Imho, chamfer doesn't like the non-tangent border of the slot opening.
That's right, but there must be more in it, because it can work as described above:
SnipScreenshot-763978.png
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Shalmeneser
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Re: Chamfer is driving me nuts :-)

Post by Shalmeneser »

I cannot 1mm-chamfer the slot opening. :cry:
* selecting the upper face : FAIL
* selecting the 4 edges of the slot : FAIL (even modifying the order of selection)
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ChamferTheSlot.FCStd
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Capture d’écran 2022-08-11 030047.jpg
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papyblaise
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Re: Chamfer is driving me nuts :-)

Post by papyblaise »

I change the order of operations: the slot , then chamfrein , round pocket , then chamfrein
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GT2_20d-1.JPG
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chrisb
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Re: Chamfer is driving me nuts :-)

Post by chrisb »

papyblaise wrote: Thu Aug 11, 2022 6:21 am I change the order of operations
See my post above :)
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papyblaise
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Re: Chamfer is driving me nuts :-)

Post by papyblaise »

See my post above
desole , I sliping tonight :lol:
domad
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Re: Chamfer is driving me nuts :-)

Post by domad »

NHSA_Rainer wrote: Wed Aug 10, 2022 8:55 pm ....
Hi NHSA_Rainer, hello to the Community!

The animated gif shows an example of the possibility of inserting a chamfer that is independently "editable" dynamically horizontally and vertically through the use of a "fictitious" Sketch that has the sole function of controlling the dimension of the chamfer.
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GT2_20d_dynamic_chamfer.FCStd
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GT2_20d_dynamic_chamfer.gif
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Shalmeneser
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Re: Chamfer is driving me nuts :-)

Post by Shalmeneser »

@domad :
* You should modify the position of the slot hole sketch to reuse the same sketch for the pocket and for the Pipe path.
* Sketch009 is outside the body for visibility, just to drive the dimensions of the chamfer. A spreadsheet should do the same but less cryptic.
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