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    • #11070
      don anderson
      Participant

      Hi …I am in the process of restoring an old bell, approx:100 years old. It will be displayed inside our church later on. It is in good shape,with a wooden wheel.The bell weighs about 225-250 lbs. I would like to bring it back to a brass colour. I have it lifted on a swivel,being able to spin it. I have seen on a video,using a powered tool and spinning the bell to remove the “patina” and to grind it down to the bare bronze or brass. I don’t know what type of abrasive disc or paper was used. Is this the proper way to go ?
      Sincerly Don Anderson
      New-Brunswick,Canada. ❓

    • #14491
      hjlong
      Member

      Does the bell have an inscription? Any process that removes metal will reduce the relief of the lettering. If you do not mind losing some surface metal, the simplest procedure would be sand blasting. If you wish to get a high polish, then you will need to begin with a bronze wire wheel and a flexible shaft or power drill to remove the heaviest grime. Then you will need to use a felt or cloth wheel with graduated grit from coarse “Tripoli” to fine “Jewelers Rouge”. Hand or machine buffing (with a circular grinder) using graduated emery discs will also sufice. Hand buffing to a high gloss is a cumbersome and fatiguing process, but can result in a high gloss. You would then need to apply a lacquer on completion to avoid future tarnish. No matter how you do it, you will remove surface metal and the patina that has been protective of the bronze for many years. If there is lettering on the bell, I would not try to achieve a fine polish, as the lettering will be affected by the polishing. If you choose hand buffing, be sure to wear protective goggles, gloves, and a particle respirator as metal dust is extremely irritating to the eyes and the airway and can lead to chronic respiratory illness and cancer.
      Harry Long, MD

    • #14492
      don anderson
      Participant

      to: hj long.
      fr: don anderson.
      Thanks for the info. There is no surface inscription on the bell,there is some engraving on it,but it is deep.
      I have started grinding with a circular emery disc (inside),and reducing the grit by steps,I have gotten good results.
      You have mentionned applying a lacquer when the final polishing is done. Is there any special type.ex:(oil based,latex based,aerosol types) ?.

      Thanks….. don.

    • #14493
      hjlong
      Member

      It depends on where you plan to display the bell and the wear and tear that it may experience. Most lacquers are quite hard and scratch and chip easily. The acrylics are softer and more durable. If you do lacquer it, use a spray lacquer. You will get a smooth, high gloss finish without the streaking of a brush or roller. Oil or water based products are useful on porous substances that absorb the water or oil but not on metal. You will need an alcohol based product that relies on evaporation. If the bell will be frequently touched or bumped, you will probably need to refinish it every year or two to avoid tarnish at sites of chipped lacquer. You may simply wish to leave it unfinished and buff it each month with Brasso like hotels do with brass/bronze sink fixtures.
      HJLong, MD

    • #14494

      Here’s a contrary opinion, offered not to Don Anderson (who already has decided what he wants) but to others who may find this discussion in the course of exploring the question of how to care for their old bronze bell (church or otherwise).

      Old bells should not be made to look like they just arrived from the foundry yesterday. The patina which forms on bronze is not corrosion, as rust on iron and most steel objects is. Rather, it is a reflection of the decades or centuries of service which that bell has given. Unless forcibly removed, it will stick tight to the metal and protect it against further oxidation, without the need for applying and maintaining any sort of artificial coating.

      An apt comparison might be your grandparents’ wrinkles, which reflect long lives well lived. While you might have pictures of them when they were young, you would not make them undergo plastic surgery to look young again.

      Frequently I see photographs of bell rehanging projects in England, where old bells may get new fittings (and even new frames) so that they can continue ringing well. Many of these photos were taken while the bells were on display for parishioners to see before being hoisted back up into the tower. In no case have I ever seen old bells polished, even when they are accompanied by a new bell or two to augment the old. Cleaned, yes – it’s quite reasonable to wash off any accumulation of dirt, bird or bat debris, etc. But a simple rinse won’t damage the patina. (Metal fittings may be galvanized or painted as a protection against rust; but rust is corrosion, not a patina.)

      In a nutshell – respect the beauty of age!

    • #14495
      maxkurillo
      Participant

      Hello Mr. Don Anderson. I just had to ring in on this one. Carl take note.
      First of all –do you know what the finish was on the bell when it was new? What did it look like when it was installed? Was it nice and shinny sparkling in the sunlight as it swung, or was it bronze colored and smooth, or was it , let’s say surface condition #400? What is the surface condition now? Inspect every inch of the outside and evaluate what you found and let us all know. A picture or two would be worth a thousand words. But since we don’t have pictures lets try a few words.
      The surface of this bell is being protected by a type of corrosion; yes corrosion. Corrosion is a gradual chemical attack which results in the conversion of metallic materials into oxides, salts and /or other compounds. There are many types of corrosive media, such as air, industrial atmospheres, water, bird and insect matter, etc, etc. You get the idea. There are two basic methods of corrosion, direct chemical attack and electrochemical attack. We can assume the bell body was not bolted, or secured to some other metal, that eliminates electrochemical attack. Now we can talk about chemical attack. An example of direct chemical attack is the corrosion of copper roofing by atmosphere. Atmospheres containing oxygen, moisture, and carbon dioxide (from products of combustion) react to form basic copper carbonate, a green (Patina), insoluble coating. In marine atmospheres basic copper chloride forms. The tarnishing of silver- ware is another example of direct chemical attack. This type of corrosion attack proceeds uniformly over the entire exposed surface of the bell surface. There are other things to look for, such as: (1) Pitting, this is a localized form of corrosion resulting in small holes that penetrate the surface, and is caused by minor amounts of impurities in the base metal or the presence of dirt or foreign matter adhering to the surface. (2) Dezincification, this results in a loss of zinc from the brass, leaving behind a porous mass of copper, and is an overall rather than localized form of attack. Before you start GRINDING away find out what you have and the surface condition. YOU CAN DO MORE HARM THAN GOOD. I go right along with Harry and Carl on this one. Clean it up and let people enjoy this old bell, it has been knocked around for a long time.
      Max Kurillo

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