1987 BMW E28 M5 Blue

Almost there with the sill, but still not quite yet


So started to piece together the rear section of the sill to Wheel arch





Thought I'd better have a bit more investigate this







Which was a bad idea, as it shows that we now have a bigger problem





The metal above the subframe is rotten, I really did not plan on having to drop the subframe as well


Heres a view from the inside





Started to undo the subframe, then thought better of it, with the sill still not fitted, the car is not exactly at its strongest, so decided to leave that, have a think about it and come back to it later


The rear of the sill, like the front, needed extending, so made this





Which goes here




But before that, need to fix the inner sill









And the inside of the arch





Then after a bit of trimming and joddling





Then a coat of zinc primer, to the inner sill and inside of the outer sill, to protect it all






Needed to add another drain hole in the new end section, to match this






So out with the Dremmel





and cut the end of my old jack handle





Placed in an open vice





and a couple of taps later, we're done






so weld that on




and dress off





then repeat for the rear door step








Then its onto the front





as requested by bstardchild, I'll try to show the cleaning off in steps, hopefully it will make sense

The first most important thing is to make sure that both pieces are perfectly level all the way along, before you weld it, the gap between them, is due to the thickness of the cutting discs used to cut it off in the first place, but this will help to ensure that I get good penetration, this is the second most important thing with a repair like this. As if you don't it will just crack once you start grinding it

then weld in spots or sections, until your all done








start with the 60 grit flapwheel





or Roloc disc for the tight spots









and power file with a new 40 grit belt on for the really tight and awkward bits








take the rough off first with the Roloc or flap disc, making sure to keep them flat with the metal and try not to dig in either side








then the power file












and a plain and simple square file for the detail





and then to smooth it all off and round the corners, a 60 grit disc on the DA












Not entirely necessary to go any further seeing as its going to get painted, put to get into the spots that the DA could not, there's always a Scotchbrite disc for the Roloc









Which just helps to smooth it all out





and jobs done






Just leaves a small spot on the centre pillar, one of the spot welds that I drilled out was a bit too close to the edge, so thought it best to partly weld that up before the sill was in place





and grind





and thats it for this weekend, seems like an absolute age to get to this point, but finally the sill is ready to go on