rosin core solder means no flux needed?

[flies]

do i need flux if i'm using rosin core solder?  never soldered before...

[Peter Snowberg]

The rosin is the flux.

In plumbing, the flux is usually separate from the solder and you usually need much more of it. In electronics things are under much more control so it's easy to pack the right amount of flux inside the solder, using the solder as a melt-able tube to hold the flux.

Flux is a generic term.

In plumbing, the flux is something that generally breaks down into hydrochloric acid to "clean" the surface being soldered to. This type of flux will eat the thin copper used on PCBs.

In electronics, the flux is made from rosin and most of the time it doesn't leave behind chemicals that continue to eat the metal.


If you're just starting to solder, I would suggest getting a solder type called 63/37 and investing all the money you can in a good soldering station. You can get a good temperature controlled station for $40 US. If you can't do that, use an iron of about 20W or so.

Remember that soldering is about practice and developing a feel for working with molten metal. The more you do it, the better you will get.

May all your builds power up first time.

Oh, if you do ever need a little more flux, you can also get liquid or paste flux.
http://www.action-electronics.com/kester.htm#Flux

[flies]

excellent.  That's what i thought, the rosin is the flux, i just got confused by listening to df't ppl on teh internets.  thanks for the tip, i got the weller 40 watt gizmo and eutetic rosin cored flux, but i was worried that i would need additional flux before i solder my first effect this weekend. 

thanks for the informative reply!

[Peter Snowberg]

The hotter the iron, the faster the flux will burn off, so if you're working with a connection that you think could use a little more flux, add a little more solder (to get the flux) and then remove the excess metal with the iron. You'll get the feel for it quickly.

40W is a little hot for delicate things, but if you move faster it will be fine.

If you want to turn the temp down a little, a standard light dimmer placed in the iron's cord will work very well. I would suggest also powering a "status" lamp so you can see what power is being fed to the heater.

Best wishes for all your soldering and building.