My Weller Soldering Gun is the Model 7200 and the tips insert differently, screw clamping as opposed to the hex nuts many of them use. I did a search (weller soldering gun tips) and found some available. Some were pretty cheap looking not having the heavy point. Those looked like they were made out of copper wire. I also found a couple of you-tube videos about making your own out of copper wire. Probably the same videos you found. I know I would prefer to have the standard soldering gun tips with the heavy end like the ones in the picture below. It may take some looking around to find the right ones for your Soldering Gun.
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