I would love to play around with electronics but I hate soldering. I hate the toxic smell and fumes, I hate the small bit of metal shards that seem to go everywhere. It's been 100 years since electronics, why no soldering alternative to make connections?!
Use a fume hood or extractor and really learn how to solder properly. It sounds like you are either running your iron too hot and/or you are trying to melt your solder on the iron and pass it to the joint. The pros use a TON of flux because it practically solves the oxidization issue and helps a lot with spreading the heat to where you want it to go. Half of your temperature issues can be solved by either preheating your boards or spot heating with a hot air rework tool.
Flux in flux cored solder is rosin, rosin is distilled from pine sap and is a permitted food additive. It’s as a glaze on chewing gum and pharmaceuticals.
Rosin is also used on violin bows to increase friction, and it’s the white powder you’ll see gymnasts and baseball pitchers apply to their hands to improve grip.
Rosin vapour is a lung irritant, so avoid breathing it by using a fume extractor, and for some people it can cause contact dermatitis.
Yes it’s horribly sticky, that’s the worst part about it really. Isopropyl alcohol will dissolve it.
Soldering makes a metal-metal connection, with the flux ensuring oxides are removed. This makes a very low resistance connection, mechanically it’s very strong, and it’s easy to automate. As a bonus it’s also very easy to undo.
Other technologies like glues and crimping have their uses but are less reliable, higher resistance, or difficult to automate.
This may change but there’s little demand. Glues have lower conductivity and are harder to remove, mechanical connectors are bulky and not as strong.
It’s the same as applying flux separately, the flux is displaced by the metal.
If you’re applying fluxed solder directly there’s not much point applying separate flux to clean metal. Of course the flux will boil off pretty quickly so you need to use extra if you’re doing something where the solder wire doesn’t directly touch the components, or if the metal is old or previously soldered.
The only advantage to non-fluxed solder for most hobbyists is being able to choose your flux, but for most of us rosin is fine and fairly non-toxic.
You could do wire wrapping like nasa still does; there will definitely be a high quality tutorial somewhere. Or if building a squashed bug circuit you could use crimps (with or w/o the insulator to be pretty)
But besides breadboards you're kinda stuck with facilitating a clean soldering setup, which is fairly easy - if you're really worried build a gloved-box. I just wear a respirator and open a window
