Electrolysis

£8 2/3 hours Very Easy You will need: A large container for the solution Soda Crystals 2 or more Electrodes (steel/iron) Crocodile clips Wire Something to hang the parts from DC Power supply

I'd been wanting to try this for a while, as the removing rust/paint from parts is always a time consuming task. I've tried the vinegar method which is good, but if you leave the part in it for too long, it will eat away at the metal as well (been there, done that!). Electrolysis seemed to have the answer - no mess, no hassle and it leaves the good metal alone. The idea is to submerge the part in a solution, then pass an electric current through it, which will separate the rust from the good metal. Fill the container with water and mix in the Soda Crystals. The ratio I used was 10g per litre. You then need to put in your electrodes. These must be steel. Iron will not last very long, and using copper/aluminium will produce a toxic solution! I ended up using two old backing trays. These will deteriorate over time, and will eventually need replacing You now need to suspend the part in the solution so that it does not touch the electrodes. I used a metal bar to suspend the part from, and hug it from some old coat hangers.

I tried a few different options for the power supply. Easiest is a cheap battery charger (more expensive ones often have an auto cut-off, which is no good, as you need a constant supply). I also tried an old laptop power supply with the end cut off and that worked ok as well. You need to connect the electrodes to the positive(+) side of the power supply, and the part to the negative(-). Get this the wrong way around, and you will turn the part rusty, rather than removing it. As soon as you turn on the power supply, you will see the part begin to 'fizz'. This is how you know it's working correctly. You can see what should happen in this video: The bubbles you can see are hydrogen, so make sure it's setup in a well ventilated area. Leave the part to de-rust for an hour, then come back and see how it's looking. This process will remove any rust, and turn pitted area's black. It will also remove paint from the surface just leaving the metal. Unlike using vinegar - the process is self terminating, and will stop when all the rust has been removed. When the part is finished, give it a bit of a wash/light scrub to remove any last traces of rust. Top is before the process, bottom is after: Over time the solution will become contaminated with rust/paint, but this will not affect it working. I am providing information on how I have done this, but I take no responsibility for anything you do after reading this.