I am reactivating this old thread since, based on your more recent posts, you still seem to be learning. Below is a picture of your Weller 260/200 Watt Soldering Gun as seen on Amazon.com
The heavy "aluminum rods" protruding from the front are actually the end connections of a one-turn secondary winding on a transformer occupying the bulk of the gun above the two-stage red trigger switch. The primary of this transformer is tapped, so activating the trigger inserts all of the primary winding or just part of the primary winding (depending on how far you pull the trigger) in series with the power line cord seen protruding from the bottom of the handle. Depending on whether all of the primary winding or just part of the primary winding is connected to the power line cord determines how much voltage is induced in the one-turn secondary. Typical voltage in the secondary (without a tip bolted in place) will be about two volts. With the copper tip bolted in place, over 100 A will flow through the tip, consuming 200 to 260 watts. The voltage at the secondary is large enough to operate two screw-base "penlight" bulbs located on either side of the gun near the lower of the two secondary winding terminals.
Notice the method of attachment of the copper soldering tip to the aluminum rods. This picture shows that a pair of "set screws" is used to secure the copper. Earlier, better constructed, guns used a threaded steel ferrule that slipped over the ends of the copper wire, which were then bent at a right-angle and pinched between the ferrule and the secondary terminals as the ferrule was screwed down into the terminals. The secondary terminals were not made of aluminum originally but of steel (or perhaps nickel-plated copper). The ferrules allowed a much higher compression force to be exerted on the relatively soft copper, deforming it and forming a gas-tight metal-to-metal seal with very low resistance. The primary reason these guns fail to heat properly is a poor, high-resistance, connection between the copper soldering tip and the secondary terminals. The change to aluminum secondary terminals has guaranteed that the steel "set screws" will eventually "strip out" the threads in the aluminum, rendering the gun useless.
Historically, the Weller soldering gun was the "go to" tool for radio and television chassis-wired component replacement. Parts were mounted on solder terminals and it took a lot of heat to melt the solder securing them. Soldering irons of that era were large and unwieldly. Solder suckers hadn't been "invented" yet, although clever technicians learned to remove the outer shielding braid from coaxial cable, dip it in solder paste flux, and use it to remove solder by capillary attraction. Today you can buy solder wick in various sizes with flux pre-applied. No need to strip out the braid from coaxial cables. But the Weller Soldering Gun is pretty much obsolete and useless for serious electronics work, being replaced by the 40 to 60 watt "pencil" soldering iron or the newer temperature-controlled soldering stations. And for surface-mount devices (SMDs) you really need a hot-air work station.
One comment you made back in the early part of this thread leads me to believe you didn't know anything about inductance, inductive reactance, or for that matter, anything about reactance and how it affects AC circuits:
As you have (hopefully) learned by now, resistance and reactance bear only one thing in common: they are both measured in ohms. Reactance, unlike resistance, has an "imaginary" component that is either positive (inductors) or negative (capacitors). Don't get too wrapped around the axle about what this "means" because it is just the way mathematics is used to describe the physical observation of reactance and what distinguishes reactance from resistance.
So... how much "electronics theory" have you absorbed since this thread was started? Built anything yet? Let the "magic smoke" out of any components yet? Acquired a soldering pencil to allow you to do some serious, modern, electronic fabrication? All that is part of the experimental process. You learn by doing.