Posted 18 January 2013 - 07:51 PM
I've just completed some extensive repairs to the floor pans and sills of my Mini (new sills, all 4 floor pan quarters, heal board ends, etc). That left a mix of clean new panels and some areas (like the exhaust tunnel) still covered in WaxOil residue and patches of surface.
I cleaned the whole belly with Mineral Spirits (white spirits) then wiped down with acetone, rotary wire brush to remove any surface rust, the another clean with Spirits/acetone. I then used POR15 Metal Prep (keys the metal), then rinse it off and let dry, then two coats of POR15, then two coats of 3M 08883 Rubberized Undercoat (4 rattle cans). Lots of work but I think it'll be worth the effort.
FYI... I used that solution because its what I had lying around my garage, but have since found it's the current favoured DIY solution for many classic restorations and off-roaders here in the USA... so I guess it should be good for a Mini :)
Cheers,
Colin.