I have two Weller's, one has to be 30 years old.
I bought it off of a Snap on truck when I worked on diesel refrigeration ( Thermo King ) in Miami FL. The units control panel and wiring harness had some heavy 10 gauge wires in it that terminated on pins in a quick connect plug. I had to have a gun that would heat hot and fast to keep from burning up the connections. I think that gun is 200 watts.
It's fallen off of ladders, trucks, toolboxes and has withstood the test of time.
A few years back I decided to go online and see if I could dress up the old girl as she was pretty rough, the case was 75% duct tape and electrical tape. Weller had every piece in stock!
I gave her two new case sides,. a trigger assembly, light bulbs and bulb holders, screws, and cord. and of course, new tips.
She burns in wire just like it's brand new.
my second Weller is a low watt gun 45 watts..it works great for smaller gauge wires and light jobs. Then there's the radio shack special.
It's one of those stick pens with a tiny tip and an on-off button I rigged onto it. It works perfect for circuit board stuff and servo wires.
I think the biggest mistake people make is the choice of solder and flux. and then heat control. Acid flux has no place near electrical wire and parts unless it's a last ditch effort to make a repair. Rosin flux only !!!! and quality thin wire solder, not the 1/8" thick stuff for plumbing!!!
And heat,,, you need enough heat for the job.
You will burn up more **** trying to solder with too low of a heat. You want a gun that will heat fast and hard... get in and out quickly. If you are spending more that a few seconds to make a solder joint, chances are something is not right.
Solder follows the heat. you should tin the tip of the gun first, then apply it to the joint, and put the solder away from the tip. as soon as the solder flows keep moving the solder until the connection is covered. As soon as it has flowed to the tip, quickly pull the heat and solder away. You will be rewarded with a nice shiny solder joint. If it looks flat and dull, either it's a cold joint or something moved before it cooled.
Practice makes perfect, so if you haven't used the gun in a while... practice on some scrap prior to making that critical joint..make sure everything is as clean as can be. Including your flux, brush, solder, tip, contact point and wire.
Flux the connection, and go for it !!
Be quick, and don't overheat the joint, if something is wrong, stop! Recheck everything and let it cool off before trying again.
Practice, practice, practice !! It will go a long way to making you a pro solderer !