Hi all,

See http://www.stovebolt.com/techtips/rust/electrolysis.pdf

Has anyone tried this? I had a quick search of the forum but could not find anything in the previous threads.

I am looking at using this method of removing rust from steel screws in a bronze component to hopefully free the screws. If i use washing soda in the electrolyte will the electrolysis do any damage to the bronze?

Regards

Rob

.

Rob

I have never tried the alchemy which you mention ( we will be turning conrods into gold next !)

Steel screws in a bronze component might respond to a little heat, even boiling water on occasions has worked for me.

Mike

The following article appeared in the March A7OC Magazine. It was originally written by Phil Allman.
I have tried it and it works, (using salt).
It does gas very freely so should be done in a very well ventilated area, preferably outside.


It is often difficult to remove rust from small, intricate parts but the following electrical process works well:
Ingredients: - plastic container, a piece of lead, a handful of salt or bicarbonate of soda and a direct current source of electricity. This can be provided
directly from a car battery or through a battery charger.
Thoroughly dissolve the salt or bicarb in a quantity of water. The rusty article is attached to the negative terminal, the piece of lead to the positive terminal and both are then immersed in the solution making sure that the two metals do not touch one another. Turn on the power supply and watch
the bubbles rise. These bubbles are hydrogen and oxygen and both are highly explosive. Do not carry out this operation in an enclosed space! The
hydrogen takes oxygen from the rust leaving a loose sludge that can be washed away, probably needing a wire brush, before applying a primer.
The time taken depends on the area and thickness of the rust and the amperage used with heavy encrustments taking several hours.
After a time, the lead will become coated with a sludge, which, if left, becomes a hard deposit and so should be cleaned from time to time. The article is unaffected but, if left in the salt solution for too long would soon be attacked. The solution becomes rusty and muddied but, as long as bubbles appear, the process will continue to work.
DO FOLLOW THE SAFETY ADVICE

Dave,

Thanks, i knew i had read about it somewhere!! The instructions on the website i gave the link to say to use a steel electrode which i think would be a lot easier as it suggests that the electrodes need to be suspended inside cavities etc. I will have to give it a go and try out the various different possibilities for electrodes / electrolyte.

Cheers

Rob

Rob

I have used this idea in both directions. To get rid of rust I used a carbon electrode out of the middle of a D cell. I also used a variable power supply to give more control.

I have also switched the polarity and using the variable power supply have etched and electro polished parts. The difference between etching and polishing is the amount of current. Low current is polishing. One can make the etching a bit selective like write a number one the head of a bolt with a permanent marker, and then etch the head of the bolt for a few minutes. Under the marker will not be etched but the rest of the head will so the number becomes permanent until filed off.
Pat

Way back when running a coachbuilding business I set up a family-sized bath and de-rusted everything successfully. I had to line the bath with plastic first, as you cannot have any contact with metal. I would suggest don't use salt, as one who lives by the sea I can tell you even salt air sets up the rust again immediately. I've never heard of the lead idea, can recommend steel as the best. Good Luck. Cheers, Bill in Oz