Has anyone any opions on the rust removing fliuds that are available? I've tried 3 : both Finnegans' products and Machine Mart's. I don't rate either of the Finnegans stuff too highly, although I have a mate who says the dip works well. When I tried it I diluted it to the recommended 9:1 solution, and it did seem to clean up one of the front brake dust plates fairly well, but it struggled when used again. Similarly I tried their gel which also claims "brings back to bare metal", but didn't find this very true either. I kept painting it on every 20 mins for about 5 hours one weekend but the deepest rust only turned black, which is probably OK but not what they claim will happen.
Machine Mart's rust remover is however a different kettle of fish. Although more expensive and only available in 1 litre bottles, it is quite superb at removing rust from albeit smaller items, getting back to bare steel when soaked overnight. I have used it very effectively on the bottoms of doors by making a trough out of plastic guttering, sealing off the ends, filling it up, and soaking the bottom of the door overnight. The next day the whole of the bottom of the door has turned back to grey metal, unbelievable! You can reuse the remover as many times as you like before it eventually gets very dirty and goes a bit thick. As I say I think this product is amazing, pity MM don't make a bigger size, and don't stock more than 2 bottles at a time.
If anyone has experience of these or any other products then I'd be very interested to read them.