Tinning a soldering iron

Flux and solder. Your alchemical "stuff" would be a flux. Not being a historical chemist, nor caring to see what google comes up with since you can do that yourself, I suggest a tin of NoKorOde as being generally useful flux-type stuff that's easy to find and not overly nasty. Zinc dichloride is the stuff generically called "acid flux" and is both more aggressive and more corrosive to other things. Make your own by dissolving as much zinc as possible in hydrochloric acid, if you like.

Flux, some solder, and heat will do you, though with a 60 year old copper (a copper is not an iron) you'd also want to remember the mantra "physically clean, chemically clean, hot but not too hot." ie - start by finding shiny pink copper before you pull out the flux and the heat. And don't overheat it or you'll burn the flux off and the solder won't tin the iron.

Yup, there used to be a "Sal Hepatica". See

But; it was a laxative :-)

I believe you meant Sal Amoniac. Used to be able to buy it in little blocks. I used it for smoke pots in theatre.

Nowadays we use Zinc Chloride flux for tin/lead solders.

with barely controlled levels of lithium carbonate - "compare poor me at

8 to happy me at 1"

There was a sal martis, ferrous sulphate, which might have been used with coppers - it forms a layer of iron on the copper, which prevents the copper dissolving in the tin-lead solders used 60 years ago (and it also slows atmospheric oxidisation of the copper, the copper oxide then dissolves in the flux).

Two main types of flux were used, corrosive fluxes like sal ammoniac (ammonium chloride) sometimes with borax added if a high temperature solder was to be used, for work on bare iron and steel.

Another corrosive flux was zinc chloride, also known as acid flux - tinkers would dissolve scrap zinc in diluted spirits of salts (hydrochloric acid), fitters would buy a tin of Baker's flux - which was also used for work on steel and iron, especially galvanised iron.

Corrosive fluxes should be washed off immediately after soldering.

The other type of flux was non-corrosive; colophony or rosin was used for copper, brass and especially tin, sometimes with a little turpentine and/or glycerine added; and tallow was used on lead pipes and other wiped lead joints. If a high-temperature solder was to be used then zinc chloride flux might be needed on copper alloys etc, but if possible rosin was preferred.

But unless you are using lead solder, which is uncommon these days, it's all different now. Most soft solders nowadays are about 95% - 97% tin, the rest silver or a mixture of silver and copper.

They flow at a higher temperature than leaded solders, so while some of the old fluxes, especially zinc/ammonium chloride fluxes, can still be used, it may be better to use a modern flux made for the purpose, which may contain acids, alkenes, amines, borates, etc.

Modern rosin fluxes may be "activated" with acid, so you have to wash them off, but they work better with lead-free solder.

And so on. Lead free solders are newish technology and the best solutions are still being worked out. Also I am a bit out-of-date on the newer fluxes ...

-- Peter Fairbrother

Zinc

****************************************** Good.... I have HCL w/Zinc so I can flux the iron with it... Great flux for galvanized materials....my tinner uses it. Sal Amoniac...I'll bet that is a laxative too. . ...thanks. . .chas

The trick my dad taught me on large irons - one wants the solder to tin an area where the work is going to be done. You don't want tin solder globing itself all around the iron.

The trick - get the iron hot and with an old shoe - use the black heel and rub the iron where the solder isn't going to be wanted.

I've used that for years. I normally use the inside of my boot heel!

I gave my 500 watt iron - black beauty - to a friend to solder gutters. Had to use welder gloves with that beauty!

Mart> I have a 3/4" sq copper soldering iron that is 60 yrs old and never been

For brazing, you can use Tippex. Liquid Paper or another sort of typewriter correction fluid to make out areas where you do not want the braze to wet.

They are made from titanium dioxide, which melts at a gazillion degrees, in some form of binder which is just strong enough to stay in place when red hot.

-- Peter Fairbrother

When I learned the trick from Dad - there wasn't a Tippex. Wasn't a Liquid Paper. And correction fluid - what a laugh. Two carbons and two onion sheets with a bond sheet on front. Would have to put a calk sheet on each and type the letter. Take out sheets (all three) and backspace to the spot to type over the correct letter.

Titanium anything was very expensive. It wasn't used in paints yet.

Besides - I always have one of those in my back pocket when needed.

Mart> >> The trick my dad taught me on large irons -

This is a VERY late reply, but I've used the big soldering coppers, you need a "tinning block", see:

It's a compressed block of ammonium chloride, aka "sal ammoniac". The hot vapors off of it will rust any bare steel in the area, remove all mikes, scales, etc. from the area before using it. Mine is a cube in a Kester box, I've had it maybe 25 years and have hardly put a dent in it. Rub the hot copper on it, then touch the solder to the cleaned area. There are some old sheet metal and plumbing books that tell how to prepare a soldering copper for use, some can be found on archive.org. If you're doing seams, you'll want two coppers, one for use, one heating up. For some things, the old methods are still best. You can also get tinning paste, which is just solder ground up in flux, dip the cleaned, hot copper in it to tin the tip.

Stan S.

chas, and everyone else,

It has been a few years since I have walked these hallowed halls of knowledge, I hate that it has to be from Google Groups, but......

To the point, chas, may I ask what you are using as a heat source for your soldering irons? I have a couple of different fire pots that I have used in the past but the propane tanks they are on are waaayyy out of date and therefore not refillable.

Thanks for your time,

Jim C Roberts

My apologies if this has already been answered.

A tinning block is ammonium chloride (sal ammoniac) which is the active flux ingredient in most 'acid core' solder.

If you can't find that item, go to a hardware store or welding supply and get some soldering paste (flux). Heat the iron, brush it a bit with a wire brush and then smoosh it around in the soldering paste and voila!

Carla

Auto correct has become my worst enema.

But first - before the flux and voila - to the sides and perhaps some of the flats - rub the hot tip on the inside of the heel of your boot or shoe. The rubber will oxidize / volatilize - something like that - and the solder won't cure the rubber onto the iron. It will smoke and smell a little, but you can run or drip solder on it and it will simply roll off.

Keeps the tips clean - solder on one side of the tip.

Mart>> >>> I have a 3/4" sq copper soldering iron that is 60 yrs old and never >>> been

replying to chas, bill242 wrote: try sal amoniac block buy online may be easiest, RadioShack used to carry them not sal hepatical

replying to chas, bill242 wrote: try sal amoniac block buy online may be easiest, RadioShack used to carry them not sal hepatical