started work on the sill mounting area & floor tonight. the bottom lip wasn't too bad in places and maybe could have been saved but i'm all for starting off with fresh metal all round, no chance of rust coming back in a few years.
still actually takes a bit of courage to get the grinder going and chop whole lumps of the car out but it has to be done. the metal left was in very good shape, just a tiny bit of surface rust colour but what is left is solid.
first off a plate is made with a 1/2" lip which will eventually become the sill mounting edge. that plate does the bottom edge then joins to the inner sill which is in great condition. i've used thicker steel for this section, 1.2mm thick. takes a lot more effort to shape & cut it but makes a much stronger job in the end. this section will be carried forward to the front jacking point area and a new jacking point made. will do the same all the way along to the rear, which will need quite a bit of work. some big holes to cover up
the plate is welded along both faces where it joins the inner sill, both from inside the car and inside the box section, this again makes for a much stronger repair section and will help make the sill area strong enough to support the weight of the car.
the central membrane has a simple strip welded to the lower edge, mainly to help locate the lip in the correct place and also helps build strength into the box section. not the neatest but doesn't need to be, strong and fresh metal are more important. will get plenty of zinc primer into the cavities before it's all closed in.
the floor will be closed in with a simple strip of new metal. will leave that until the sill box section is complete as it can then be overlapped the sill repair sections to regain full strength.
takes a fair amount of time tomake each patch and get it fitting reasonably but it's coming along.