Thread: soft soldering

My father did a lot of soft soldering

He used non electric type irons that he borrowed () from work and when out of shape reformed by heating and beating back into shape

this type...http://www.woodworkforums.com/f40/so...g-irons-18748/

I think he has some of Dads in that collection..had all of them and more...

I often helped in the shed on weeknights and weekends.

He would place his irons in a home made or should I say greatly modified kero stove.

When the irons were hot enough one took from the stove and dipped into a "solution" to clean the iron tip (i also recall doing this at tech school), else you'd have or may have troble when soldering due to contamination/scale etc.

I kept some of better irons when he passed and now I need to do some soldering.

I have some solder (the stuff he prefered...with lead), and bakers flux and spirit brushes, but what was the "solution" for cleaning the tip of the iron...I know water formed the main constituent but there was something else in it. Any one know what is was and percentages?

Also the sound the iron made when being dipped to clean would also tell you if the iron was hot enough or too hot.

The normal flux for soft soldering is zinc chloride. This is what Bakers Soldering Flux is and it states this on the container.
You can make it yourself by adding zinc to hydrochloric acid (in a glass jar is best). Fizzes like mad and gives off hydrogen and quite a bit of heat. You need to leave it till it stops reacting and there is still some zinc remaining. The result is what is termed 'killed spirits' if I remember correctly and Bakers put it in a nice black container and charge you a huge amount of money for the privelege of buying it.
It is all you need for cleaning and tinning your copper iron and for the flux when soldering.
Have been using this for the last 50 odd years since doing a trade course at school.

Alan

Its good to see these old methods revived.
Yes. have done a lot of soft soldering, over the years & "Killed Spirits" Zinc Chloride was the best flux for most metals.
When soldering galvanised sheet steel however, used a diluted straight Hydrochloric Acid, as that would combine with the Zinc coating (galvanising) to produce Zinc Chloride.
The copper soldering "Iron" or "Bit" as we were taught, was heated & when a constant light green flame came off it was an indication that the temperature was right. It was then dipped in the flux & a coating of solder applied to the tip.
Overheating caused the copper tip to be "burnt" which then meant filing to clean it up, fluxed & tinned again.
Still use the blow lamps & "Soldering Irons" occasionally.
regards
Bruce
ps If Graeme (Anglesmith) happens to be reading this he will recall these methods, as taught to us at Ashy Tech 60 yrs ago !

Originally Posted by Abratool

Overheating caused the copper tip to be "burnt" which then meant filing to clean it up, fluxed & tinned again.

So what was the white(?) block for?
(I should know this but I've forgotten)

Stuart

Stuart
This is a bit of a "please explain" moment for me, as I cant recall or know of any white block???
regards
Bruce

Hi Bruce,

(as I recall) When retinning tips we used a block of "something", rubbed the hot iron on it(smoked nicely for us kids) then put some solder on the tip. So it was some sort of flux I assume but it want the flux used for soldering the work(which would have been most tinplate or gal.

I'll have a look around and see what I can find.

Stuart

p.s. found it. Sal Ammoniac
Cleaning soldering iron with sal ammoniac block - YouTube

Originally Posted by Stustoys

Hi Bruce,

(as I recall) When retinning tips we used a block of "something", rubbed the hot iron on it(smoked nicely for us kids) then put some solder on the tip. So it was some sort of flux I assume but it want the flux used for soldering the sork(which would have been most tinplate or gal.

I'll have a look around and see what I can find.

Stuart

p.s. found it. Sal Ammoniac
Cleaning soldering iron with sal ammoniac block - YouTube

thats the stuff

but what was the solution..i didnt think it was killed spirits...might be diluted killed spirits...or was it just a diluted hydrochloric??

just found out that you can use Bakers flux or killed spirits to clean the oxides off the tip

But Hydrochloric acid was used in the old days
This was used when doing a lot of soldering as diluted Hydrochloric was always easier (less time involved) to make in the larger quantities needed for the dipping of hot irons and subsequent evaporation loss ...but at a greater hazard...ah... the old days when you could do anything anything without SOP's, MSDS's, WMS's, OHSW, etc etc

eskimo,

As mentioned above home made killed spirits or Bakers Soldering Fluid was the usual flux for general soldering, though hydrochloric acid could also be used for galvanised iron where the acid was neutralised by the zinc on the galvanised iron. However, resin based soldering fluxes were also available and popular for smaller jobs. These worked particularly well on brass, tinplate and copper. In the case of copper when electrical connections were involved the resin based fluxes were less likely to produce connections which failed due to corrosion over time. The best known of these resin fluxes was Fluxite, but, being American, it was not generally available here for some time after WW2 because of restrictions on imports from dollar currency areas. Various similar paste fluxes were made locally - I still have about half a tin of GUD Soldering Paste which I must have bought in the fifties. It is still used occasionally.

The sal ammoniac tinning blocks are still available, e.g.

Stained Glass Supplies SAL Ammoniac Tinning Block 1 2 LB | eBay

Frank.

Added: I was typing the above when your last post came up. I suspect using straight hydrochloric acid as a general flux would often have caused corrosion problems later unless the post-soldering cleanup to neutralise the residual acid was very thorough.

Originally Posted by franco

eskimo,

As mentioned above home made killed spirits or Bakers Soldering Fluid was the usual flux for general soldering, though hydrochloric acid could also be used for galvanised iron where the acid was neutralised by the zinc on the galvanised iron. However, resin based soldering fluxes were also available and popular for smaller jobs. These worked particularly well on brass, tinplate and copper. In the case of copper when electrical connections were involved the resin based fluxes were less likely to produce connections which failed due to corrosion over time. The best known of these resin fluxes was Fluxite, but, being American, it was not generally available here for some time after WW2 because of restrictions on imports from dollar currency areas. Various similar paste fluxes were made locally - I still have about half a tin of GUD Soldering Paste which I must have bought in the fifties. It is still used occasionally.

The sal ammoniac tinning blocks are still available, e.g.

Stained Glass Supplies SAL Ammoniac Tinning Block 1 2 LB | eBay

Frank.

Added: I was typing the above when your last post came up. I suspect using straight hydrochloric acid as a general flux would often have caused corrosion problems later unless the post-soldering cleanup to neutralise the residual acid was very thorough.

Franco

I know all about killed spirits and that its used as a flux to clean the material to be soldered.
However, I am talking about the solution that Dad dipped his iron's into immediately after taking them off the kero stove and before soldering. This was to clean the tinned tip section of oxides so they would not hinder or be carried across into the solder often allowing pinholes or poor soldering ...pinholes were a no no for what Dad was doing after hours...new galv petrol tanks for something..never did ask what they were used for... Proline Tanks knew...but they are long gone too

Any way I found out the info as stated above from an old timer 50ish at Consolidated Alloys

Dipping the iron into the resin flux is also a good way to clean the tip.

I have a major soldering job coming up shortly on the petrol tank of my 1927 Chevrolet, where the tower which holds the petrol gauge (yes, it is mounted on the tank, not the dashboard) has partly separated from the tank body. I suspect getting the 86 year old metal of the tank clean enough to tin properly will be a major challenge.

Frank.

Originally Posted by Stustoys

Hi Bruce,

(as I recall) When retinning tips we used a block of "something", rubbed the hot iron on it(smoked nicely for us kids) then put some solder on the tip. So it was some sort of flux I assume but it want the flux used for soldering the work(which would have been most tinplate or gal.

I'll have a look around and see what I can find.

Stuart

p.s. found it. Sal Ammoniac
Cleaning soldering iron with sal ammoniac block - YouTube

Stuart
Thanks so much for this information.
I must say I have never used or heard of Sal Ammoniac, or (Ammonium Chloride) being used for cleaning Soldering Iron Tips, however it looks to be very effective.
The conventional Killed Spirits or "Bakers Flux" does not always do a great job on the tips.
So my next purchase is to get hold of a block of this locally, to assist with soldering.
If any one has any suggestions on a source that would be appreciated.
Thanks again Stuart, one never stops learning !
regards
Bruce

Heat it up and wipe off the liquid solder with a rag. Then you can just file the iron lightly back to copper and re-tin it. I am having a workshop clean out at the moment and re-discovered five irons which went into the bin. I am sick of keeping stuff around that I have no use for and having inherited those and a lot more stuff from Dad & his Dad I am over the sentimental thing.

Sorry, haven't read all the posts so it may have been answered but when I did my sheet metal apprenticeship (a couple of years ago or more) the tinning solution was 50/50 killed spirts/Bakers Sol and water. You filed up your tip, heated, dipped and had solder sitting on a little piece of copper plate and meted solder all over your tip and away you went.

Originally Posted by Claw Hama

Sorry, haven't read all the posts so it may have been answered but when I did my sheet metal apprenticeship (a couple of years ago or more) the tinning solution was 50/50 killed spirts/Bakers Sol and water. You filed up your tip, heated, dipped and had solder sitting on a little piece of copper plate and meted solder all over your tip and away you went.

ah ah we seem to be getting closer...i thought it was a mix...Dad always made his own for dipping as did tech school..he always had hydrocholoric around and bakers so I wasnt sure what the mix was but you have confirmed what the guy from Consolidated has said

so a 50% bakers water solution seems the trick ( i dont want to make killed spirits anymore as the last time i made it the bottle blew up...hydrogen can bulid up some pressure ..i used to send balloons skyward..very lucky that day)