The Talking Machine Forum — For All Antique Phonographs & Recordings

I'm a big fan of phosphoric acid as well Covah. It strips rust from steel & iron, and verdigris from brass, but leavings any plating (or paintwork) totally intact.

[quote="Retrograde"]Boy that Flitz Metal Polish worked well on those knobs. I'll have to remember to pick some of that up sometime.

General note to anyone reading, be very gentle using 0000 steel wool on plated phonograph/gramophone parts. The plating is usually very thin and can be damaged or removed before you know it.

hydrofluoric acid? [/quote]

The Flitz Polish works really well, but it requires a lot of elbow grease. From what I can tell, you can rub to your heart's content and you will not remove the nickel coating.

Hi, what is this Covah product you mentioned? Flitz polish works well, but it is a lot of work.

Buy phosphoric acid by the gallon at the hardware store. As pointed out above, it does not dissolve top coats. Sometimes the finish got freshened in the old days with a coat of shellac which turns brown and nasty. Then you need to soak metal parts in lacquer thinner to remove top coat then in acid for rust. I would never use metal polish, just 0000 steel wool and dishwashing detergent. Nickel is tough. Wash gold with sponge only.

Acid good for crank shafts, escutcheons, casters, screws, exterior parts. Parts under the hood are usually not so rusty although I often soak brakes in acid since brakes get gunked up. Scrub with a toothbrush.

Be sure to soak parts in baking soda solution to neutralize acid.

Do you dilute the acid? If so, how much?

Phosphoric acid out of the jug is pretty mild, a lot milder than hydrochloric acid.

I think the winding-keys always look so rough because they were nickel plated directly over the steel crank, and as the plating fails / wears away, the steel begins to rust.