removing rust

Cleaning out the study today and came across a heap of transformers - old mobiles, printers etc. Converted one to act as a very low amp battery charger - it's connected to an old gel battery now so I will see how it goes.

Two of the others (240v to 9v & 240v to 14v) I tried some experiments I had read - heard - dreamt about??? I connected up a very rusted part on the -ve lead and a clean ferrous rod on the +ve lead and suspended them in a solution of washing soda and water. Turned it on and left it for a few hours. Result the rust migrated from the part to the ferrous rod and left the part black colour and rust free. The solution gets very brown and the rust forms like a scum on the top of the solution and on the rod. Once you turn on the power you can observe bubbles streaming from the part.

It would appear to be an ideal way to remove rust from small parts or metal sheet (old bike side covers etc.) without damaging them.

aussie wrote:Cleaning out the study today and came across a heap of transformers - old mobiles, printers etc. Converted one to act as a very low amp battery charger - it's connected to an old gel battery now so I will see how it goes.

Two of the others (240v to 9v & 240v to 14v) I tried some experiments I had read - heard - dreamt about??? I connected up a very rusted part on the -ve lead and a clean ferrous rod on the +ve lead and suspended them in a solution of washing soda and water. Turned it on and left it for a few hours. Result the rust migrated from the part to the ferrous rod and left the part black colour and rust free. The solution gets very brown and the rust forms like a scum on the top of the solution and on the rod. Once you turn on the power you can observe bubbles streaming from the part.

It would appear to be an ideal way to remove rust from small parts or metal sheet (old bike side covers etc.) without damaging them.

I was looking at this the other day, lots of videos on youtube. Must try it sometime.

I haven't studied chemistry for a lot of years but I believe the bubbles are hydrogen gas.

If this is the case then lots of ventilation and no smoking or else KABOOM!!