This ain't supposed to happen. The break is defiantly not at the weld. As you can see I was cutting a piece of fresh beech almost to the limit of the saw but I was not forcing it. The wood was only felled last week and was part of the heating logs I had delivered on Saturday.
I'd been using the BS or about 40mins, straight cuts only, to round off some lumps of beech that came with the logs for the fire. The blade broke cutting the last one.
How common an occurrences this? Is it more likely operator error than manufacturing defect? I do not know the exact age of the blade but as I do know it's provenance I know that it would not have been abused before I bought it.
Here are some shots of other pieces before and and after I rounded them off.