Hand re-tinning of copper cooking utensils?

A. You must use nontoxic flux (tallow or rosin) and pure tin (lead free!).

A. Peter,
Like your father, I recall very similarly. I was born in Pakistan, and all of my grandmother's pots and my mother's pots were made of Copper inside and upper half of the outside of the pot was tinned, and the rest was always BLACK, mostly from cooking on wood and coal stoves. Once every year this guy would come to your neighborhood, he would show up around 6:00 am, come and get a bucket of water from my mom, and go set up, we worked on the ground sitting down, would set up a coal fire and have this air puffing bag from which the tube when right under the fire . Mom would have me take a cup of tea for him first, then I would carry out all of our pots to him, go over to get all of my grandmother's pots. by about 8:30 am he was surrounded by piles of pots from all the neighbors. I would just sit there and watch him take all these dull looking post one by one and make them Shiny and New with just a few strokes of something powdery on wool/cotton balls that smoked a lot, followed by a Stick of tin, as if he was buttering the pot, and then again that Smoky powdery stuff (Flux as I know it now).

Donna,
I must say, my mother and grandmother would totally not agree with you on how delicately you have to treat tinned pots. These were the work horses of their houses. They used metal utensils in them all the time. and it used to be my chore to scrape out the bottom of the pot if something got burnt, and I used a metal spoon to scrap off most of it and then used a lava rock to take out the stubborn parts. I must say also that I never really saw the copper showing. Yes all the pots got tinning every year, so maybe that is why.

A. Before trying to re-tin a copper utensil or vessel, it must be chemically clean. To remove all the oxides, you can immerse it in a solution of 10% sulfuric acid in distilled water. Use only copper or plastic tongs to handle the item in the pickling solution. The copper will develop a pink color when all the oxides are removed. Following the pickle, scrub the surface with a clean felt pad and 4F pumice powder [on eBay or Amazon] . Rinse with distilled water and a clean brush and you are ready to re-tin. Flux with rosin or tallow and use the purest grade of tin [on eBay or Amazon] you can obtain. The tin is best pre-melted in a tinner's pot [on eBay or Amazon] , and the work piece pre-heated to around the melting point of the tin or just a bit more. The flux will be merrily smoking, but should not burn. Pour a bit of molten tin into the pot and quickly wipe it around with a clean cotton rag saturated with flux. Dump out any excess tin and wipe with the fluxed rag until the piece cools enough that the tin has fully set. This should result in a nice shiny tin coating.

It's been more than 30 years since I did this, but that is my best recollection.

A. My father was a sheet-metal worker; he showed me how to re-tin. One flux he learned to use in trade school is powdered rosin, but he preferred powdered sal ammoniac [on eBay or Amazon] (ammonium chloride). When we needed it, I made it by filing the tinning block until the heap of powder was big enough. "Killed acid", muriatic acid [affil links] with an excess of zinc, also works. We tinned pots on the stove top with the help of a blowtorch for the sides, or over the plumber's charcoal stove meant for the lead pot used for joints in cast-iron pipe. We used "block tin", that is to say, pure tin, in the form of tubing salvaged from an old beer distribution system. Now, I use lead-free solder consisting of tin-silver eutectic, about 4% silver, the rest tin [on eBay or Amazon] .

I clean the copper with muriatic (commercial-grade hydrochloric) acid [on eBay or Amazon] and rinse with soft water or not at all, then heat the pot as quickly as reasonable so there's not much time for oxidation to build up. I rub the solder on the pot with plenty of sal ammoniac powder. When the solder starts to melt, I wipe with cotton rags to get a smooth coat. Mostly, it's easier than it sounds. If a patch won't wet, 00 steel wool [on eBay or Amazon] fixes that. Keep some handy.

A. Hello Karen. Not sure if you had your questions answered yet, but the darkened tin does not sound right to me. My wife has copper. We use Barkeepers Friend [on eBay or Amazon] to rid the light stains caused by cooking ... brings the surface to almost new again. One tiny spec of missing tin should not hurt anything, if you bought the pan new retail, then it should be covered no questions asked. Good luck.

A. I'm ignorant when it comes to retinning copper cookware, though I have attempted it several times. I seem to recall having read that an alloy of copper and tin forms a layer between the "pure" copper and the "pure" tin, AND THAT the melting point of this alloy is higher than that of the tin. That's how I explain to myself the irregularities in my retinning.

P.s.. Buying pure tin, food grade, is easy - in large quantities.

P.p.s. Here in the UK commercial retinning of a pot costs between 25% and 50% of the price of a new, identical pot. The cost of the tin is at most 50 p/1$ for a large, but not gigantic, domestic pot.

A. I've cast thousands of bullets made of a mixture of lead and tin. Far and away, the best flux is [on eBay or Amazon] . For an amount of molten tin enough to fill a one-pound coffee can, all you need is a ball of beeswax [on eBay or Amazon] the size of a pea.

Melt the tin, drop the pea in, and stir down and through as though you were folding shortening into dough.

The wax may flame up. Don't worry. Tin does not burn.

But never, never have water anywhere near your melting pot.
In fact, I warm the stirring implement on a stove to make sure it is absolutely dry. A very little water added to molten metal makes a spectacular eruption.

Last, Lee Manufacturing, who make molds and other tools for bullet casting, sell a very inexpensive electrical melting pot.

Again, if you are to melt metal, stay away from water.

A. Tin melts and flows at 231° C. or 447° F.
Lead melts at 326° C. or 618° F.
Copper melts at 1083° C. or 1981° F.

It is why you can tin lead pipes together, but it is risky as the lead can melt before you realize how hot it is.

As for the tinning and use of copper pots. You need to clean the pot to the bare metal. You can do this by pickling, or by abrasive blasting which is much easier.

There are commercial fluxes available, but by and large the process is best left to someone with experience. Heat the cleaned pot to about 450° to 500° F.; the tin will melt and flow, and stick to the copper where there is flux. I would not recommend wiping with cloth because the cloth could catch fire, and you might just burn yourself. I prefer a ball of loose chain to swirl the tin around in the pot to give an even layer, although it will never be completely smooth unless electroplated. Once cool, the outside of the pot will need some cleaning and polishing, and the inside should be soaked and washed with a vinegar [in bulk on eBay or Amazon] solution then again with soap and water to remove residual flux.

The tin as it ages will oxidize somewhat turning it dark gray or black which in no way interferes with the barrier between the copper and the food, and the tin will not react with foods being cooked. If you must have it bright you can scrub it with Ajax [on eBay or Amazon] and a plastic abrasive cleaner.

Do not deep fry or get the pan hotter than 400 degrees as you risk melting the tin. It is not a good idea to overheat oil in the pan prior to cooking and the pan should have contents in it at all times while cooking so that the pan does not overheat.

To clean stubborn stuck on foods. simply fill the pan with water and detergent and let it simmer for a while. The gunk will wash right off. Tin is a relatively soft metal and can be scratched through to the copper, so wooden implements are recommended.

A. To Re-tin Pots:
1. Only do it outside, don't try it on your electric stove
2. Use heavy leather gloves to handle the pots Use extra heavy cloths to protect your hands also wear eye protection.
3. Use only N-F grade bar tin (Food Grade Tin) Goggle your local non-ferrous metal supplier you will pay 10-20$/lb depending on quantity.
4. Clean the pots very well to remove grease and carbon deposits
One option is to put pots in dishwasher with Lye (Sodium Hydroxide) 1-2 oz. and some regular dish washing compound. Put on "pot and pan wash" and do it twice.
5. scrub pots with 00 steel wool [on eBay or Amazon] and rinse well, then put pots in 5-10% solutions of either hydrochloric acid (Muriatic) or Sulfuric acid. (Highly corrosive, Use heavy rubber rubber gloves [on eBay or Amazon] and eye protection [ goggles [on eBay or Amazon] ] (Do outside and do not Heat) for about 20 minutes.

6. Use either natural rosin or zinc chloride flux depending on your position on using chemicals. LOL (I'm a chemist).
7. This is the important part:
The item should be hot enough to melt the tin at all parts you want to work on, it should not be so hot that the tin oxidizes too rapidly.
Brush some flux around the pot
8. Melt some bar tin in the pot and swirl it around
Immediately begin wiping with a heavy cotton cloth
9. If you do it correctly you will end up with a bright smooth coating of tin.
This is where the art begins and the chemistry ends.
It won't be pretty the first time you do it. Don't give up
Good luck
David

A. Hello,

You can tin your own pot, and burn your mucus membranes down to the bottom of your lungs.

Historically, A trained coppersmith would rub Sal Ammoniac into the copper container, while rubbing bits of pure tin into the surface with a linen rag ( high temp. ) The smoke is the Sal Ammoniac going into vapor, it will rust anything near by.

Copper pots were often dunked in sulfuric acid to clean them, but depending on the culture, you just wanted the tinning, here is a master craftsmen at work.

youtube.com/watch?v=mXZGsosR-1E

Copper exposed about the size of a dime is not harmful. Actually the copper is not the issue.. it is the green stuff and only the acetate not the carbonate is poisonous (but who can tell by eye-they are both green).

Cooking in copper...if you are boiling water you can have clear copper vessels, if you make tomato sauce (acid) you better have it tinned for the flavors.

Some folks have copper sensitivity so please take that into account. Many folks take copper by the pill to supplement their diet ... go figure.

A. Hi, Omar. People may want it to be tin not just because they like the color of tin but because tin plating is 'food safe' whereas copper is not. Copper pots, for example, are periodically retinned, so we appended your question to a thread on that subject.

I would suggest that you not attempt to develop a tin-colored patina for anything that might touch food; instead please have the copper plated with lead-free food-safe tin. Good luck.

Regards,

A. I am an avid antique collector and love cooking. I have a lot of copper pots that need retinning. I found a number of articles by searching "retinning copper pots". I found a source for the tin. It is:
Rotometals
San Francisco, California
I just ordered 5 feet of 1/4" food grade tin. I will attempt a retinning. I have to find some zinc chloride flux.

A. Rosin - get it from a music store if there is no other source - used to rosin the bows of stringed instruments. Same Stuff...

I have a couple of White Mountain ice cream makers (always a hit here!) - but the tinning of the cans has failed - so they need re-tinning - so we'll try the HCl pickle approach first.

A. Hi Eric. Are you sure that the coating was nickel? It absolutely wasn't stainless steel. It was probably tin, so we appended your inquiry to a thread about tinning, which gives you instructions.

Electroplating for school is indeed not rocket science; we have an FAQ, "How Electroplating Works" including a demonstration so 3rd graders can do electroplating with safe kitchen chemicals in five minutes. 3rd graders can also be taught to plink out "Twinkle, Twinkle" on a piano in five minutes, but I would hesitate to say that after such a 5-minute session that they are either platers or piano players :-)

I don't think you will achieve what you consider successful nickel plating short of making a major commitment, because there's a lot more to robust plating than what you saw in school; but if you can proceed without hurting yourself, you can certainly try. Good luck.

Regards,

A. Nickel plating is sometimes used to line copper cookware, but is mostly decorative. Nickel can be toxic, so ...
Historically copper was lined with pure tin to make it food safe.

? So the Muriatic acid solution did not remove the tin on the bottom edge of the pan? Did you ever figure out how to remove the tin? What did you do?

Well, I'm no expert, but I have fried with tin-lined copper with no issue. I think that as long you have oil or food in the cooking vessel then you're fine.