I bet it was done on a turning center with live tooling and the coolant wasn't aimed right. Chips piled in the corner get welded and not washed out.
Once you take it off the machine it is difficult to fix it and you probably don't see it until it is off.
No real effect on usability but ought to have been cleaned up.
Once you take it off the machine it is difficult to fix it and you probably don't see it until it is off.
No real effect on usability but ought to have been cleaned up.
