Your main problem is you don't understand the skill of soldering which is necessary if your reviewing a soldering iron. Just a hot iron will not solder wires together even if they are tinned, as they require a constant flow of fluxed solder. With the thick wire moving around the heat is not being concentrated on the copper, and you can't use pliers to hold it, as this will act as a big heat sink and draw the heat away. My credentials are 60 years working with electronics.
Your main problem is you don't understand the skill of soldering which is necessary if your reviewing a soldering iron. Just a hot iron will not solder wires together even if they are tinned, as they require a constant flow of fluxed solder. With the thick wire moving around the heat is not being concentrated on the copper, and you can't use pliers to hold it, as this will act as a big heat sink and draw the heat away. My credentials are 60 years working with electronics.