- Practical advice
- Restoration: what care for which metals
- The iron
- The cast
- The copper
- Restore an iron object
- Restore a cast iron trinket
- Restore a copper object
- Restore a brass object
- Restore a tin object
Over time, crafts made of iron, cast iron or copper are tarnished. Good products, adapted tools and some simple gestures are enough to give them a second youth and revive the shine of the metal.
Most of the chemicals mentioned are irritating or harmful, by contact or inhalation. Work outdoors or in a well-ventilated room, wear impervious gloves, goggles and, if possible, a thick apron.
Utensils (pots, pans, etc.) used for culinary purposes should be rinsed thoroughly with soapy water to remove traces of products. These are indeed harmful!
To avoid reoxidation of the metal, it must also be isolated from the humidity of the air. The varnishes for metals, to be applied with a brush or better aerosol, find there their full utility. The protection is durable, without yellowing over time. Disadvantage, the metal loses some of its brilliance. On the other hand, the interview is facilitated. Spray varnish light and regular sail, 20 cm from the surface.
Restoration: what care for which metals
Falling into oblivion, metal objects now appear as decorative pieces in our environment. Everyone tells their story. Thus, this basin, which our grandparents used to warm the beds, or the rack on which the cauldron was suspended in the hearth. Sometimes, it is during a trip that one discovers the "real memory", such as this Turkish coffee grinder marinated at the flea market of Athens or this tinned copper jug, bitterly traded in Dubrovnik.
No matter where they come from, these handcrafted objects were made from a base metal such as iron, copper or tin. They usually ask for few repairs. The enhancement work is mainly deoxidation, followed by polishing and protection to prevent the return of gangrene.
It is the most basic of all metals since, for centuries, it has been used to make utensils, tools, weapons... Its serious fault is to be sensitive to rust, which gnawing inexorably. We must not seek to eliminate it completely, but simply to stop its devastating effect. A slightly attacked surface, of irregular texture, gives much more authenticity to the object. Renovate, in this case, is to restore, not refurbish!
The only method to overcome deep corrosion is sanding. A fine sand jet is propelled under high pressure by compressed air on the element to be stripped. The rust is pulverized, and the piece is fully exposed, as new, which is not the goal.
To clean a rusty object without too much to remove its patina, remains the mechanical method (scraping, brushing, sanding...) or chemical, or even the combination of the two. A first brushing with a manual wire brush removes rust scales. It is useless indeed to waste chemicals and energy on non-adherent parts only asking to leave! A rust-destroying treatment based on phosphoric acid (Julien, Frameto, Libéron, Syntilor...) removes the rest.
- Brush the piece with a brush or soak it in a small container if its size is suitable.
- Dilute the acid in twice its volume of water.
- Leave to act for several hours. Only a whitish salt remains on the surface and disappears on rinsing with clear water.
- The wiped, dried part has a bluish gray color.
Be careful not to confuse destroyer and rust transformer. The first removes it, the second changes it into a blackish gangue which, after drying, can be painted.
Mechanical stripping complements the action of the deoxidizer. The ideal is to use a drill dimmer and a set of brushes: disks, bells, swabs... Depending on the size and shape of the piece, it is the whole drill-brush that works on the placed object in the vice (or with a hose). Or, the drill is held fixed on the work bench with a special support, and the part brought into contact with the rotating brush. Just after the chemical treatment, use a large hard brush to remove the final glitter. A second pass with a softer brush will be used for finishing. Nylon wire brushes loaded with abrasive grains are also very effective for this stripping. They just ask for less pressure on the room. Adjust the speed of rotation of the drill according to the indications on the accessory packaging. Otherwise, start with a low speed, and increase according to the results obtained.
The chemical and mechanical treatment completed, it is necessary to prevent the return of the rust on the metal laid bare and, therefore, vulnerable. The simplest of protections is to pass the piece encaustic, preferably hot, and polish with woolen cloth. There are also transparent protective varnishes in jars or aerosols (Julien, Libéron, Véraline...).
This material is similar to iron, but it is brittle and its surface condition is often less regular. For fireplace accessories (fireplaces, andirons...), apply a wrought iron cream with a brush or cotton wick. Leave to dry for a few hours then polish with a cloth or brush. This graphite black paste, once lustrous, gives a beautiful dark gray patina with silvery highlights. The wax can also be used and even shoe polish that will play with the colors! Be sure to protect yourself from stains!
This soft metal hardens when worked, mainly by hammering. In its pure state, it is orange-red in color, but is involved in the production of several alloys. Associated with tin, it produces brass, golden yellow color. Married to zinc, he creates the bronze, greenish. Unlike iron, the oxidation of these metals is mainly superficial and results in the appearance of verdigris. The renovation of copper objects or its alloys is done in the same way, and with the same products. Before starting the restoration, make sure that the metal has not been previously covered with a varnish. If so, expose it with a chemical cleaner.
In the presence of a very tarnished copper, use a specific deoxidizer for nonferrous metals. Apply it to the surface of the object with a rag or cotton wick. If necessary, insist on stains with extra-fine steel wool pad (No. 000) with moderate rubbing. Leave on for a few minutes then rinse with clear water and wipe dry.
Excluding the products of the trade, there are many recipes of grandmother! One can, for example, immerse the object in a solution of soda crystals (two handles per liter of water) saturated with sea salt. Bring it all to a boil. As soon as the metal regains its original appearance, rinse and dry. The combination of vinegar and coarse salt is also an effective method! Pour the boiling vinegar over the salt (three tablespoons per liter). When the salt is almost melted, immerse the object and soak until completely cool. If the object is large, rub with a cloth soaked with this preparation.
Once deoxidation is complete, the decorative object must be shiny to obtain gloss. This is obtained using a polishing paste. According to the manufacturers, it is called "polishing pot", "shine polisher" or "cream of the Pêniers". Apply the dough regularly to the cotton wick, rubbing in small circular motions until the desired result is obtained. Let dry a few minutes and polish with a soft cloth or a clean cotton wick.
Do not try to treat the tin with acid because it would irremediably attack the metal. It is not advisable to thoroughly strip tin, although the products mentioned above are also suitable for their removal and maintenance. It is enough to give them a certain shine by rubbing them with a wad of cotton wick dipped in hot beer, or even with steel wool soaked for the most fouled parts.
Tin is sensitive to cold. At temperatures below -10° C, it is covered with black spots: it is the "plague of tin". Scrape off these stains and rub them with pure ammonia. Then polish with steel wool 000.
Restore an iron object
This very oxidized rack was once enthroned in the hearth. Use a metal wire brush to remove non-adherent scales and then carry out a chemical treatment with the rust remover.
After rinsing, the part is ready for mechanical stripping. The drill, mounted in its support, is equipped with a brush with hard strands. Hold the object firmly to move it over the rotating brush.
For more precise work, especially in nooks, a bell brush is passed over the object firmly held in a vise. Abrasive nylon brushes are particularly well suited.
After the exposure of the metal, it must be protected against the return of oxidation. Use a special metal polish that has been thinly layered with a brush. There are also aerosols, easier to use.
The handle of this Turkish coffee grinder has an iron part. To pick this kind of delicate parts, you can use a small brush mounted on flexible, much more manageable.
Restore a cast iron trinket
The same brush is also very effective to access the hollow parts of this cast iron chenille. The layer of rust that covers it is only superficial and can end with a hand brush.
Using an old toothbrush, apply an iron and cast iron cream, which will protect the fireplace accessories from heat and rust. Insist on the hollows but spread the surplus well.
Leave to dry for a few hours then polish with a cloth or brush. The cream gives a nice gray patina anthracite thanks to the graphite it contains. Treat the reliefs to accentuate the nuances.
Restore a copper object
This copper basin is tarnished without being deeply oxidized. To remove these marks from the weather, use a pad of steel wool 000 soaked in copper deoxidizer. Rinse with soapy water.
Place on a cotton wick some Crème des Poêliers and work the surface to be polished in small circular motions, until the pad is dry. Repeat the operation if necessary.
Leave to dry for a few minutes then polish with a cotton wick or a clean, dry cloth until you get a nice shine.
Subsequently, this cream will serve you for the regular maintenance of brass.
Restore a brass object
The renovation of this load cell, whose front face is brass, is done in the same way. Graduations, somewhat oxidized and clogged, are to be treated particularly to enhance them.
The iron back, ring and hook are treated with an abrasive nylon brush. To avoid the return of the oxidation, to pass to the wick of cotton a layer of encaustic liquid on the whole of the object.
Restore a tin object
This tinned copper jug has beautiful chiseled patterns.
To clean them, use a small soft brush mounted on flexible.
Work gently to avoid damaging the metal.
Tin is renovated with the same products as copper, but it is necessary to avoid destroying its patina.
A less aggressive method is to scrub the surface with steel wool 000 soaked in hot beer.