plating, anodizing, & finishing Q&As since 1989
Historical hand re-tinning of copper cooking utensils?
An ongoing discussion from 2003 through 2015 . . .2003
Q. I have some old copper pots that my grandmother used in Damascus Syria, she is now 102 years old, she and my father recount a hand tinning process where when they could see the copper coming through the cookware they would send it to the chap for re tinning, dad remembers a guy heating the pans up and then wiping them with a cloth with some substance and the finished product being shiny and new looking. From a historical point of view just wondering what the process was.
Thank you and regards,Peter Malavisi
hobbyist - Busselton, Western Australia, Australia
A. You must use nontoxic flux (tallow or rosin) and pure tin (lead free!).Goran Budija
- Zagreb, Croatia
Q. I am interested in the physical process of retinning copperware. I believe that a sulphuric acid wash should be used to remove corrosion from the utensil before the rosin/ tallow fluxing. Comments or advice please.Merv Baer
- Christiansted, St. Croix, US Virgin Islands
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 [affil. link to info/product on 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 you can obtain. The tin is best pre-melted in a tinner's pot, 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.Rich Waugh
- Christiansted, St. Croix, US Virgin Islands
A. My father was a sheet-metal worker; he showed me how to retin. One flux he learned to use in trade school is powdered rosin, but he preferred powdered Sal Ammoniac
[affil. link to info/product on 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. link to info/product on Amazon]
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.
I clean the copper with muriatic (commercial-grade hydrochloric) acid 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, 0000 steel wool [affil. link to info/product at Rockler] fixes that. Keep some handy.
- Kendall Park, New Jersey
Q. I recently bought a french pan, nicely tinned and shiny inside as well as out. I used it once--a little light frying in vegetable oil. I washed it, rubbing it with a sponge to get out the slightly darkened grease. Now it is quite cloudy and messy looking. Is there anything I can do. Also, there is one spot about the size of a pin head where the tin is out. Is that dangerous? Thank you.Karen Orren
home owner - Los Angeles, California
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 [affil. link to info/product on 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.Reuben Quezada
- Tujunga, California
July 13, 2008
RE: the fellow who did a little frying in his tinned pan.
- Addison, Texas
Q. I want to retin a copper pan. Can you suggest a place where I could purchase the right tin and also what flux to use.
prototyping - Montreal, Quebec, Canada
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.
- Canterbury, Kent, UK
April 5, 2008
A. I've cast thousands of bullets made of a mixture of lead and tin. Far and away, the best flux is
[affil. link to info/product on Amazon] For an amount of molten tin enough to fill a one-pound coffee can, all you need is a ball of beeswax 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.
- Coquille, Oregon
July 25, 2008
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).
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.
- San Francisco, California
June 30, 2008
Q. How to change colour of copper into tin? I was asked how to change the colour of copper I want the method because people are always wanting it tin.omar alaa
having company - Cairo, Egypt
June 30, 2008
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.
Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey
August 31, 2008
Q. Retinning pots and pans in Mexico --
My question is : Retinning pot and pan ... is this something currently done in Mexico ?
I have skillets and pans to retin... would anyone know?
- Mazatlan, Sinaloa, Mexico
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 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 [affil. link to info/product on 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.
- Kensington, Maryland
March 8, 2009
Q. Hey, my name is Doug, I'm a metalsmithing and jewelry graduate from the University of Oregon.
I've been doing some copper vessel forming and would like to do my own tinning, but I am having trouble finding materials.
Is there an affordable place to buy block pure tin? Rio has some high prices for it.
Is the rosin flux mentioned similar/same as the flux powder used by baseball players?
If not, where can I get rosin?
Any assistance would be greatly appreciated!
- Eugene, Oregon
May 1, 2009
Q. Hello, I need some help here please. I used to be a full time baker ,many years ago, and used to have my bowls sent out to be re finished. Well now I have some used equipment that I am using at home and the mixing bowl is in pretty bad shape it has a few small dents but the inside finish is terrible. I've called the local shops and no one seems to have a clue what I'm talking about. Does anyone out there? I believe the bowl is steel. any help would be appreciated its an older model 20 quart bowl from hobart, yes I can buy a new one but would prefer not to spend 150.00 bucks Thanks in advance.
hobbyist - Callahan, Florida
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:
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.
- irwin, Pennsylvania
September 24, 2009
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 steel wool 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 [affil. link to info/product on Amazon] and eye protection [ goggles [affil. link to info/product on 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
- Seattle, Washington
January 11, 2011
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 Sulphuric acid to clean them, but depending on the culture, you just wanted the tinning, here is a master craftsmen at work.
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.
barnhart studios - lake in the Hills, Illinois USA
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.
- Cape Tribulation, Australia
March 5, 2012
Q. I've got some copper pans I bought used that appear to have a thinning stainless steel (not sure) coating on the cooking surface. I want to "re-coat" the thinning areas with nickel.
I was thinking of making a 10% solution of phosphoric acid (I've got a jug of 75% technical grade) in distilled water, drop a few chopped up nickel coins in it and let them dissolve for a day or two and then make shift a "dabber" with a stainless steel screwdriver with cloth wrapped on the end hooked up to the positive of a 12/6 volt car battery charger that has 2 amp, 15 amp and 100 amp and the negative to the copper pan or just use a 12 volt battery.
This is a "small" makeshift project. I do have a degree in chemistry but have done limited electroplating; vaguely remember a couple of labs in college. It wasn't exactly rocket science.
Any suggestions on how to make this project more successful with what I've got? I don't have any sulfuric for the solution. I plan just to dab on the Nickel Phosphate I make with the makeshift charged dabber on to the clean copper exposed areas to "recoat" the surface.
- Rogers, Arkansas, US
A. Hi Eric. I doubt that the coating was nickel and it certainly 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. 3rd graders can also be taught to plink out "Twinkle, Twinkle" on a piano in five minutes, but I would hesitate to say they are then able to play the piano :-)
I don't think you will achieve what you consider successful nickel plating, because there's more to robust plating than what you saw in school; but if you can do it without hurting yourself, you can certainly try. Good luck.
Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey
June 22, 2012
Q. I have an old heavy copper pot that the bottom cracked on. My father-in-law said that in New York, they would "take it to the coppersmith and he would put a new bottom in it." But we are in Dallas now. The pot has been passed down and we would like it fixed. Any suggestions?Ken Boozer
- Dallas, Texas, USA
August 20, 2012
Q. Just re-tinned an 8" crepe pan yesterday. Partial success. I cleaned the pan in 10% HCl. The bare copper was brilliant but the remaining tin on the inner sides was largely unchanged. I put the pan in an oven at 550 degrees with a piece of sterine (tallow) inside. I melted tin in another vessel. I had a linen rag ready. I took the heated pan and poured the molten tin in and wiped it around. The tin took to the copper beautifully. It did not take to the original tin on the sides. What do I have to do to remove the old tin or at least prepare it for re-tinning. I also got some molten tin on the outside of the pan which was hell to remove. I guess that I will have to size the outside of the pan with whiting and gum arabic? Since I am an organ pipe maker by trade, this is what we do to prevent solder from going where we don't want it. A little whiting, gum arabic and water makes something similar to poster paint which you apply by rubbing it in very well with a rag. In pipe making, we use 3 coats. 2 and 3 applied with a brush. I think I would use at least us 2 coats for re-tinning. Any comments? Help??Jim Lauck
- Otsego, Michigan, USA
May 19, 2013
Q. 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?Peter Jones
- Catharpin, Virginia USA
May 17, 2013
A point of view:
I've been cooking on copper, both tinned and what the French call "zinc" (which may be a nickel-zinc compound) for about forty years, first as a professional and later as an amateur.
My thought here is that how you feel about the care of tinned copper has a lot to do with what you know and feel about cooking.
Let's divide cooking processes into three levels of heat, plus a few sub-types:
a) boiling water (up to @240 degrees--poaching, steaming, soup, slow-cooking, like for beans;
b) frying (up to 400 degrees, including most kinds of oven-roasting; remember that although the inside of your roast may not get above 140 deg., it's the hottest point of contact between the metal and the food, or air, or radiant heat(broiling) that counts to the pan.);
c) Holy Mama: (above 450 deg.) all broiling, high-temperature sautés like steaks or chops whose goal is caramelization or blackening of food to a degree better suited to a Weber grill.
*d) there are also lots of a & b compound processes like chili or fricassees (e.g., coq au vin) where you brown (fry) something, then add liquid and maybe vegetables and stew it for a while. Pot-wise, this is frying (although if you don't mind washing pots, you could do the browning in say, cast iron and the stewing in a more fragile pot.
*e) a special case is sugar. Caramelization starts at about 225 deg. and goes to @350 deg., just below frying oil. Pot-wise, this is frying too.
*f) Another offbeat variant: slow-cooking that gets hotter than you think it does. if you're a rice-rinser, you're just boiling, but if you cook rice by the absorption of a finite amount of liquid (like a pilaf), you think of it as boiling, but that brown layer of rice at the bottom of the pan tells you otherwise, and your hot-wipe tin will be blistering soon.
If you haven't already gotten the repeated message, hot-wipe tin is a creature that adapts well only to group a), above, good only to sub-300 degrees (or, as the second pot of that brown-in-steel, stew-in-copper combo). It's great in that range--have you noticed how pasta sticks to French enamel, but not to tin? No, the tin won't turn into a puddle until 450 degrees, but it gets softer at high temperatures, will craze, crackle and scratch more easily. Also, get some nice olive-wood spoons and flats--or rigid silicon spatulas if you must be high-tech--and leave the metal utensils in the drawer.
For group b) stuff up to about 350 deg. sustained, consider modern stainless with copper-sandwich bottoms. You can scrub them back to a shine with Brillo and green scrubbers if you don't go to full deep-fry temps. 360 degrees and above, you need either that Weber Grill, or oil-seasoned cast iron, or old-fashioned French black steel (yep, they rust if you don't dry them.)
In short, if you let your mind even THINK of using the word "fry" in the same sentence with "tinned copper pot or pan," you've already made a serious mistake, from which there is no return without tears.
- Alexandria, Virginia, USA
September 19, 2015
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.Luai Alyahya
- Riyadh, Saudi Arabia
Ed. note: For those who are really into this subject, please see also letter 29192, "Need relining/re-tinning of copper pots, pans, & cookware: do it for me or tell me how to".