I made these tongs from a previous pair that have outlived their initial use https://www.furaffinity.net/view/36460303/ This pair here.

What I did was cut off the old rivet, take the two halves apart.
I then forged one of the jaws into a rough tube shape and then fit in a .25 inch piece of rod to fill in the void and forge weld it into one solid piece. I then split that piece down the middle two make the rather nice split jaw seen here.
There was a bit of issue with this since the steel had a few cold shuts (sharp corners that got folded onto itself and forming a crack in the piece) that kind of made it a bit fragile in the sense of structure.

To fix that problem, I wrapped copper wire around the areas that had cracks and I heated the tong halves up in the forge until they were red, took them out to sprinkle on borax powder as a flux and allow the copper to flow, put them back in and ramp up the heat just a bit so the copper can flow into the cracks near the pivot point of the tongs.
It worked pretty well and that brown to orangey red crap you see all over the jaws is the copper residue. When in the forge, it sort of likes to flow all over the surface that was touched by molten borax.

These tongs now hold 1 inch thick round stock.

These tongs have been proven to be a failure in a manner of minutes fumbling around with them in my hands. First off, the area where the jaw connects to the hinge plate portion is too thin and weak. They will not hold up and will bend from the shock of the metal being hit with a hammer.
These are a failure and can be learned from.