Bronze sculpture: Removing paint & refinishing

Mineral Spirits

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A. Hi, Elaine. Maybe the patina is only on the areas where the paint has worn or chipped off, and there is probably no easy way to know whether there is a patina underneath the paint. So if someone suggests a method, you should recognize that maybe there was no patina, rather than their method removed it :-)

I'd try removing the paint with a strong non-aqueous solvent like turpentine ⇦ this on eBay or Amazon [affil links] , mineral spirits ⇦ this on eBay or Amazon [affil links] , or if necessary "Aircraft Stripper" (much more noxious). Organic solvents like this should not attack metal. Avoid water based citrus solvent (which might dissolve the patina), and with as little rubbing as possible (not that I've actually done it though).

If you do end up needing the methylene-chloride based aircraft stripper, be extremely careful: you need not only goggles ⇦ this on eBay or Amazon [affil links] and rubber gloves ⇦ this on eBay or Amazon [affil links] , but outstanding ventilation. Do it outside, standing upwind of the work.

In the worse case you may need to restore the patina or let it restore itself. Good luck!

A. Hi, Joy. Avoid "caustic" strippers, plus the patina may not be fully adherent and may be slightly soluble in water, and certainly in acid, which is why I would minimize rubbing and avoid citrus solvents, which I suspect might tend to dissolve the patina.

The Aircraft Stripper is very noxious to humans, and requires goggles and rubber gloves, and excellent ventilation -- but should prove harmless to bronze. Good luck.

Regards,

Ed. update March 2020: Amazon and some other places no longer offer any methylene chloride based strippers. It's possible that they are no longer available to non-professionals due to their toxicity.

A. Turpentine (mineral spirits) can perhaps do it, Peggy, and I see no reason to suspect that it would damage bronze. But if that doesn't work, what almost surely will work is "Aircraft Stripper".
But this is methylene chloride, and really toxic -- so goggles ⇦ this on eBay or Amazon [affil links] , rubber gloves ⇦ this on eBay or Amazon [affil links] , and really good ventilation (outside and upwind) are required. Good luck.

A. Several years ago some well-meaning, but uninformed, member of my church painted our 128 year old bronze church bell with aluminum fence paint. I managed to remove the paint (it was only on for a few days) using oven cleaner ⇦ this on eBay or Amazon [affil links] and a soft scrub brush. (Several applications.) Doing it outdoors it all "washed away" with the hose, so no paint stripper to deal with. Also, it didn't destroy the original patina of the bronze bell!

A. You can use any solvent base paint stripper (methyl ethyl ketone or DMF based)! 4 parts acetone ⇦ this on eBay or Amazon [affil links] Warning! highly Flammable! /1 part ammonia ⇦ this on eBay or Amazon [affil links] (25%) mixture is usable too. Cleaned object must be well rinsed and then dried with acetone or pure alcohol.

Good luck!

A. Hi, Javier. If we rule out mechanical removal and chemical removal, we might be left only with wishing it away :-)

I believe you will find that organic paint strippers, like methylene-chloride based Aircraft Stripper, will have no bad effect on the bronze. But try it in an inconspicuous place first, of course. But methylene chloride is really noxious stuff, so a full safety protocol is in order, including goggles ⇦ this on eBay or Amazon [affil links] , rubber gloves ⇦ this on eBay or Amazon [affil links] , and excellent ventilation (outdoors, working from upwind).

Regards,

A. Barry's idea is a good one that I didn't think of! Just make certain that your stuff really is solid bronze first. I don't like to even think what a torch will do to plaster or fiberglass, or maybe even a bronze plated zinc die-casting.

Regards,

A. Hi Isi. How tall is this statue? If you're confident that it's actually a 15th century bronze casting, and you're planning on a hobbyist playing around with it, count me out :-)

One recently sold for $558,000 USD; as Goran noted, this kind of stuff is for a professional metals conservator, not internet advice based on a pic or two.

Regards,

A. Hi Anne. I suspect that you are right that this is cast bronze, but you might check with a magnet to make sure it's not cast iron.

A rule of thumb is that solvents will rarely affect metals, but acid & alkalis can harm many metals. So you can probably use turpentine or other solvents as previously discussed on this page, but make sure your paint stripper is not caustic-based!

I'm no artist, so not someone to take artistic advice from, but I think bare bronze will look sort of funny looking. I think it needs to be repainted. However, I don't think you can just slap on one uniform color of paint either; I think someone with artistic sense (maybe you, maybe a friend) needs to repaint it with some light & shadow.

Luck & Regards,