Originally Posted by Big Al
I had to look that big word up
Do you have a link to the specific products you recommend? May give them a whirl
I don't have any specific links, but it's all cheap Chinese stuff off ebay! I use a combination of 115mm cutting disc, 100mm face grinding disc, and 4mm diameter ball point burrs in a die grinder for gentler work on smaller pitted areas. When I have ground out as much as I can/dare I chemically remove all remaining rust and sometimes lead fill the area. I find that the harder a material is, the better diamond abrasives cut, and whilst it scores the sound metal quite heavily, it doesn't seem to actually remove very much.
I always use a needle scaler first to remove the flaky rust as it's considerably quicker and less damaging, plus it will show up apparently sound but very thin corroded areas by punching trough or indenting, which it will not do on full thickness material.
Diamond abrasives are cheap enough to try out these days - you might like them!
I learnt the hard way never to encapsulate rust with the magical 'turns blue' garbage - as we know, the rust is still lurking ready to burst out beneath the microns-thick passivated surface...