Chamfer fail

[Karakurt]

When you specify chamfer distance equal or bigger to the length of a face that distance is measured on it fails to create a shape.
But why? I was expecting it to simply cut through. I guess there's zero or negative size face to be rendered, but you could simply add a check for that.
Maybe the one which is generating an error right now

[drmacro]

The short answer: because that's the way it works.

The long answer is the OCCT modeling kernel that FreeCAD uses won't allow a chamfer or fillet to consume adjacent faces.

Until the OCCT folks feel like expanding those capabilities, this how it works.

[domad]

When you specify chamfer distance equal or bigger to the length of a face that distance is measured on it fails to create a shape.
But why? .....

Hi Karakurt, greetings to the Community!
I see it's the first topic you post, so a welcome.
First of all I suggest you to read the forum rules, then to insert the data of the FC version together with the system on which it is installed (menu -> Help -> About FreeCad: push copy and then paste it).
Certainly you cannot make a chamfer (or a fillet) in which a dimension exceeds the length of the side on which it insists, the softwre of my knowledge all point out the impossibility of completing the function, the reason you have already mentioned and technically deepened with simplicity from @drmacro (I think it would be a mistake to force the code, it would generate cascading errors and unexpected results).
In FC it is not possible to make the chamfer / fillet ("Chamfer" or "Fillet" function) which has the same size as the side on which it insists, to solve it you have to set the size a few thousandths less.
If you want to get a lot of precision, to overcome the problem, you work with the shearing (or cutting) function through a Boolean or slicing operation (Wb "Part" -> Slice Apart) or even pocket in the case of the Wb " Part Design ".
The above suggested applies to both the Wb "Part" and "Part Design" Wb.