Newsgroups: rec.crafts.metalworking
Subject: Re: Re-tinning Copper Pans
From: dingbat@codesmth.demon.co.uk (Andy Dingley)
Date: Sat, 31 Dec 1994 20:37:10 +0000

In article <101260004@hpcc01.corp.hp.com>
           lucasd@hpcc01.corp.hp.com "Richard C Lucas" writes:
> How does one go about re-tinning a copper fry pan?  Is the tin electroplated,
> or can one buy pure tin and flux and re-tin the thing themselves?

Old copper pans were hot-tinned, new cheap ones are flashed over with a
nastily thin layer of electrochemical tin.

I *did* have a long text on how to re-tin, but I've lost the damn thing. Not
to worry, I'm such a sad git I'll spend New Year's Eve re-typing it.....


Copper pans are tinned with tin. Anyone thinking of tinning a pan with a tin
& lead based solder would do well to study the fall of the Roman empire, and
their fondness for cooking in lead pots. The world's first artificial
sweetener (whose latin name I have forgotten) was made by boiling grape juice
in thick lead pans, until it was reduced to about a quarter of its original
volume. The active sweetening ingredient in this stuff was lead acetate,
which is undeniably sweet.....  Cynics would argue that the artificial
sweetener industry hasn't changed much since (except that Searle Monsanto
have bigger lawyers than I do, so I won't)

Back to the pans....  Re-tinning is a fairly simple process, although you may
need some sizable heating equipment.

   Wire wool

   Tinning stick

   Flux (zinc chloride / killed spirits / Bakers fluid)

   Moleskin (This is a cloth pad, made of layers of denim or cotton corduroy
   stitched together and wiped with plumber's tallow)

   Brazing torch (gas & blown air, or a big petrol / paraffin blowlamp. Don't
   use oxy-acetylene, as you need a lot of heat, but not a high temperature)

   Brazing hearth (A pile of broken firebrick. Pans are big & shiny, and so
   are difficult to heat in the open)


First of all, check that the handles are heatproof. Some pans (i.e. Ikea)
have cast "brass" (sic) handles that are actually made of some sort of
cheese. Get these hot and they'll crumble ! It's perhaps safer to drill their
rivets out, and replace them later.

Clean the old tinning with wire wool, until the surface (tin or copper) is
bright & shiny. Coat with flux.

Arrange the pan in the hearth so that you can heat it up easily, get to the
areas that need work, yet aren't losing too much heat to the surroundings. If
you can work on the whole area at once you'll get a better finish, but if
your heating gear isn't quite big enough, it's better to finish it in stages
than to try and work on the whole pan when it's not hot enough.

Heat the pan, trying not to oxidise the tinned side. It's best to heat from
the outside. As the pan gets hot, apply the tinning stick. Then use the
moleskin to rub the molten tin into the surface until it is well covered by a
smooth layer. Keep the moleskin slippery with tallow, just enough to stop it
sticking and burning. If you need to, heat the tinned side directly, but try
not to oxidise the tinned surface or you'll get a dull grey finish.

Allow the pan to cool naturally. Rapid cooling or quenching runs the risk of
distorting the pan. There shouldn't be any need to acid pickle the copper (as
for brazed or silver soldered coppersmithing), as you shouldn't need to heat
it that much. When cold, polish the copper up again, using your favourite
polishing rouge.

--
Andy Dingley                             dingbat@codesmth.demon.co.uk