Electrolysis Cleaning a Cannonball

[ms99]

Dug up a small cannonball the other day when out with some friends.

Found this guy down about 14in in an area where the French and Prussians did battle in 1793.

Here are a couple pictures - getting it home and most of the dirt knocked off, and just getting started on the electrolysis.

Using a 12-amp car battery charger and washing soda in the solution. Friend said to let it work for about 20-hours.

Will post some 'after' pictures when done.

[ms99]

Before and after 12-hrs of electrolysis.

Going to give it another few hours in the tub.

Anyone ever try a couple heavy duty rubber bands to hold the wire on the item being cooked? Just curious if it is possible to do this without a big C-Clamp in the tub? Round things are a little tough to attach the wire.

[ms99]

After 20+ hours still some hard chunks of rust on this thing.

When do you stop?

Is there such a thing as too much electrolysis on something like this?

[emoryjim]

I will wait for the experts to answer your questions -- but it looks a heck of a lot better so far.

[Trickworm]

That cannonball looks great!

[ms99]

Well after 30+hours in the tub and the wife complaining she was getting cold (complaining the needle on the electric meter spinning so fast the breeze was too much for her ) I decided to take the cannonball out of the tub.

It still has a couple areas of pretty hard rust that the wire brush and screwdriver won't knock off, so I guess that is just how it will have to be.

Doesn't look too bad. I'll give it a soak in some fresh water overnight, bake it a bit in the morning, then wax it up in the morning.

[sweendog]

came out pretty good considering the age. Nice work

[Rudy]

Originally Posted by ms99

After 20+ hours still some hard chunks of rust on this thing.

When do you stop?

Is there such a thing as too much electrolysis on something like this?

It's a great improvement over what you started with.

What you may have are some areas of high electrical resistance in the badly rusted areas. These don't get much electrolytic action because the surrounding areas have much lower resistance and rob all the current available. You could try "spot" action electrolysis by submerging only the badly corroded parts in the electrolyte solution thus forcing the current to flow through the rusty parts.

One way to do this is to soak a rag with the electrolyte and using a sheet of metal (stainless?) for the anode (the + side of the power supply), covering it with the soaked rag, and placing the cannon ball --rusty side down-- on the soaked towel. Put the thing inside a pyrex pan or something to keep the mess from spreading. Careful to not cause an electrical short.

[ms99]

Finished cleaning and baking. Now just waiting for the bee's wax finish.

Looks like 4lbs and about 2 3/4in (~7 cm) diameter.

Now to find out who fired it - French or Prussian

[sweendog]

Wow. Came out GREAT!

[ms99]

Guess it is French.

Kolby - Thanks for the tip on how to check.

[matmit]

I can't believe how well that cleaned up!
I can believe the surrender flag for the French

[PhotoRob06]

Wow that looks great!

[Weekend Warrior]

That looks great

[Carson]

Awesome find and nice job cleaning it!

I love your setup.

How does it do for smaller items? Too strong?

[GIGS is 90X]

Nice job on the cleaning. I'd hate to be on the receiving end of that cannon.