I would say that quite often you come across wires and parts that are practically not tinned with ordinary rosin, even in an alcohol solution. And the point here is not the oxide film that formed during long-term storage, but rather the specific coating of the part or wire.
Ordinary copper wires, pinkish in appearance, can be tinned without problems, even after long-term storage.
But there are also wires whose cores have a shiny, beige color. And now they practically do not tinker. To manage to tin them, you need to very persistently flick at them with a heated soldering iron. As a result, there is a high probability that the main braid of the wire will melt, which happens in most cases.
The solder practically does not stick.
As for the Chinese connectors, such as “tulip” and others, it’s the same story. You can't just take a connector and tin it. Before doing this, you need to grind off the soldering area with a file to remove the shiny coating. And only then can you solder the wire to this connector.
I think many of you have experienced this problem.Of course, some expensive flux can probably solve this problem. What if you don’t have one at hand? What if it’s not even in the store? A folk super remedy – citric acid – will help you out.
To solder wires you only need a few granules. Pour it out and take some solder with a soldering iron. We put the wire on these citric acid granules and tin the wire with a soldering iron, as with rosin.
And everything works out absolutely without problems!
The same goes for the connector.
I was personally surprised by such a simple secret for soldering “difficult” connectors. Everything is soldered like clockwork, without a hitch.
Liquid flux
Liquid flux can also be made from citric acid. To do this, mix it with ordinary water in a 1:1 ratio and pour it into any tube (for example, drops for a runny nose). And you will just have liquid flux, which will always be useful to you.
I will be very grateful if you share your secrets or homemade soldering compounds in the comments.
