I have used a single rectifying diode to lower power of 60W Chinese soldering iron due to overheating.
Though I am pleased with the result, I still plan to have variable power output for heavy soldering.
This is where I got the idea of PWM.
I am thinking of rectifying the mains with a full wave rectifier as I have found that these soldering irons work with DC as well. Then stepping th mains to 9V for the 555 timer in PWM configuration (the circuit I used is the electronoob's one) feed it to an NPN BJT and use the soldering iron in series with the collector. Additionally I plan to use the 13003/5/7 as the BJT (I also plan to use it in a Darlington pair for higher gain.)
Shall I go for it? Is there any problem with this method? Also I am compelled to use only 555 as the PWM source.