Solder Flux?

[Walesey]

Hi all.

I don't know if this is the right forum for this question, but it is the closest forum that I could find. Can anybody tell me a recipe for liquid soldering flux?

I know flux is not hard to buy, but a friend had some on the weekend that he said another friend had made, but he could not tell me the recipe.

I am interesting in soldering nickel steel model rail track to copper coated PCB and also soldering brass to brass, copper, steel, etc. A water soluble flux would be good, but one that you did NOT have to wash off would be better!! (eg, similar to Carr's Red, which de-activates with heat)

Thanks
Walesey

[doug1]

There is a liquid rosin flux used for electronics ( surface mount componentry) which would suit what you are doing I know its a commercial product but it wont corode the items your joining

let me know if you need more informaion

Doug

[Skew ChiDAMN!!]

The old fashioned recipes are simple: plain ol' NH4Cl (Ammonium Chlorate) for tin & "general" use, HCl (Hydrochloric Acid, also used on early PCB's) or ZnCl2 (Zinc Chloride) for Galv Iron. From memory, good ol' Baker's Soldering Fluid is HCl.

I can easily see why the trend has been to move away from 'em though! :wink:

[durwood]

I think the one your mate is talking about is skew's zinc cloride or what we used to call "killed spirits"

It is made by using hydrocloric acid and throwing into it some form of zinc.
We used to use zinc sheet which was thin sheet zinc which had was like a gauze ( riddled with holes) but any zinc coated metal worked. Such as gal nails, gal sheet etc.

You just kept adding the zinc until the bubbling stops which meant the hydrogen was released and you end up with zinc cloride.

I think thats correct from memory ???

[Skew ChiDAMN!!]

You just kept adding the zinc until the bubbling stops which meant the hydrogen was released and you end up with zinc cloride.

I think thats correct from memory ???

I think you're right, but I'm working from vague memory too. As kids we used to pull dry-cells apart for the Zinc casings, cut 'em up and throw 'em into ol' glass Marchant's lemonade bottles (I think 'twas Marchant's? Maybe Tarax? With the "wing-nut" resealable lids?) full of HCl and stretch a balloon over the top.

The ol' man kept the remains after we'd finished, I'm pretty sure it was for use as flux, and us kidleys kept our Hydrogen filled balloons. :thyel:

Ahhh... how times have changed. Would you trust your kids to play with Hydrochloric Acid? Come to that, would you let 'em play with Hydrogen? :oo:

[HiString]

If you were just soldering lead to lead then Styrene wax is used, but anyway, contact a stained glass supplier as there are numerous fluxes available within that industry and from memory, some are relatively harmless.

:cool: