That would vary greatly depending on the type and density of the metal, along with the dimensions of the particular piece.
The weight of a piece of anything is the volume times the density.
4 lbs.
You can weigh any size.
Nobody has tried to weigh it yet.
It is usually not the weld but the metal right beside the the weld. If a piece of metal needs to be welded, it may be getting thin in other places and when it is welded, the heat from the weld can weaken the metal and in some cases cause the metal to crystallize and be more brittle than it was.
14 pounds
200 pieces weigh 33 lbs how much does each piece weigh
It depends on how big the piece is.
500g
1 gram
Depends on the model
About 6 pounds a piece.
6.875g.
40lb
100000000000000000
Not very much, unless if you use a metal buffer tube.
800000000 lbs or your mother
5 grams