Review on Weller 7235 Replacement Soldering Pack by Todd Amarsingh

I've gone through three of these with my soldering iron. Somehow the solder destroys part of the connection to the ferrule and then wears down the wire until the connection breaks. A tip was not even enough for 4 rations. The tip becomes extremely malleable, once you heat it enough to solder it will bend and break. I would like to know what my old soldering iron tip was made of that lasted 30 years and never had a problem. Weller needs to redesign the tips or find a solution. It's ridiculous that they're so expensive and short-lived.