"Restore dark doorknobs; don't know if solid brass or not"
Q. My house was built in 1907, with some fine details. I recently polished a gooky old lamp bracket to discover a lovely brass glow beneath. Now I'm wondering about the doorknobs. My husband believes that their dark exterior is a matte finish; I think it's 97 years of grime etc. We've started playing with them; I soaked in a mixture of vinegar & Baking Soda , which began to reveal what looks like a copper color. Did a bit of polishing with Brasso [affil. link to info/product on Amazon], but not getting very far. Should I keep going or is this a mistake?Marion Rogers
homeowner - Guelph, Ontario, Canada
A. Try a magnet. If they are magnetic, they are plated iron or steel and you may be worsening things. If they are non-magnetic, and they really date to 1907, I think it is very likely that they are brass and that they can be restored to a brass color.
Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey
A. If your knobs are brass you can use 5% solution of ammonium citrate(pH9)!This is mixture of 50 gms citric acid/1 lit water, and some ammonia (25%) must be added (to reach pH 9). You can use cold or hot solution(80 °C).In case of brass plated iron you can use 5% citric acid solution, or ammonium citrate 5%, but pH must be 3,5. Rinse well. Think about some good clearcoat.
Good luck!Goran Budija
- Zagreb, Croatia
February 8, 2022
Q. I was very eager to try this as I have an amazing vintage brass ashtray that has gone a little pink after Brasso, but even with the ammonia citric acid water mixture, it's not changing -- any suggestions?Vanessa perkins
Hobbyist - Toronto Canada
February 10, 2022
A. Ammonium citrate (50 gms citric acid ,add some ammonia 25%, pH must be 9) can be used hot.(80 °C temp.) Prolonged immersion in cold solution can be helpful too.
Hope it helps and good luck
- Cerovski vrh Croatia