Ultrasonic Cleaner and Bronze

[zboss]

Has anyone used an ultrasonic cleaner on things like old bronze throughhulls, anti-siphon valves, etc...

I am wondering about the best way to clean up some of these items that are about 30 years old but probably still serviceable with a good cleaning.

I have attached a pic of some of the items I want to clean up and reuse if possible. Maybe I am just better off buying newer modern valves?

Is that blue stuff corrosion or electrolysis?

- z

[Cavalier]

Originally Posted by zboss

Has anyone used an ultrasonic cleaner on things like old bronze throughhulls, anti-siphon valves, etc...

I am wondering about the best way to clean up some of these items that are about 30 years old but probably still serviceable with a good cleaning.

I have attached a pic of some of the items I want to clean up and reuse if possible. Maybe I am just better off buying newer modern valves?

Is that blue stuff corrosion or electrolysis?

- z

The blue stuff is partial corrosion on the surface of the copper content of the Bronze and is quite natural (it's called patina).

Two steps to cleaning, firstly the inside:

You can clean the inside by soaking it in vinegar and then using an old toothbrush to remove more stubborn items, re-soaking in the vinegar as necessary. If you can see in, check the seal areas as some valves use non-metallic seal-area which may need replacing.. you can check this by half-cocking the valve so you can see the area of the seal on the ball.

...then the outside:

Rinse your bronze items in warm water, and dry thoroughly.
Place some baking soda in a dish. Drip some lemon juice onto the baking soda and mix until a soft paste forms - the mixture will bubble..Apply the paste to your bronze item with a small polishing cloth. With a polishing cloth, rub the paste onto the item using small circular motions. Allow the paste to stay on the item for 10 to 15 mins. Rinse the item with warm water to remove the paste and buff dry with a clean cloth. Repeat as necessary.

You could use ultrasonic baths, but at the end of the day you'll mostly be trying to remove salt-based accretions and patina, both of which can be removed with acetic and citric acid (vinegar and lemon juice)

[Cavalier]

..also, forgot to add:

After cleaning, you can use a couple of hose-clamps to connect a garden hose to one side of your value.. apply water pressure from the mains.. if you cycle the valve manually a couple of times and then close it, and you observe no noticable leakage from the 'visible' downstream side of the value then you know you're good to go up to.. 5-7bar pressure if you're in Northern Europe or around 3-5bar (43-72psi) if you're in the US...

[zboss]

Cool thanks. Just about all the bronze parts on the boat are patina-ed. I really like the look (its rather salty) but its not great for maintainability. I am researching getting all the items sodablasted to bring them back to their bronze coloring and then applying some I want to get a good look of whats under the patina for the stuff in the bilge. Probably leave the ports patina-ed.