How to add a fillet?

Just an observation: A chamfer adds support and strength to intersecting surfaces, but it still introduces stress risers that can cause cracking at the angled intersections. In the bracket under discussion, the stress riser caused by the 90 degree intersection of the two surfaces is reduced by the chamfer, but it still has stress points at the 45 degree intersections of the chamfer with the original surfaces. The use of a radiused fillet that is tangential to the surfaces provides the least amount of internally induced stress and greatly reduces the chance of cracking. That being said, it’s probably not worth the effort in this case – the chamfer should be fine.

I can’t open your file. I refuse to accept the EULA for anything above SU 8.
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