Apply to the welding of the copper plate. When there is no soldering flux, the welding pile will appear, and what flux can be used to solve this problem.
Can help to buy some pens or buy low solid content of flux, if after welding residual, with cleaning agent.As for what flux well, I don't have a good answer for you, if you say I'm advertising, of course it is best not to sell the market to buy the best buy accessories, big brands, such as Alfa, 1000, Kester., is this a few international brands.
Just use Alfa RF800. I've been using it
It's OK to weld it with rosin ribs
