In doing some bridge rehabs, I have ran into a welding symbol that I have never seen. It is a solid dot located at the joint between the arrow head and the tail (where the field weld and all-around symbols go.) It is not an all-around symbol that is smudged. There are several instances where there is this black dot with an all-around sybol around it.
I am just curious what this is used for.
Thanks,
Greg