Hi,
I'm changing the roof skin on my 924 to get rid of the leaky sunroof (and to learn). I haven't done anything like this before, I have got half way through un-stitching the donor skin and got a bit stuck in the windscreen corner. I have done some research and had a thorough look at it myself so I'm going to put a detailed description together, sorry if its a bit lengthy.
I have drilled out most of the spot welds on the 'new' roof section and have cut the weld lines where the skin is welded on over the c-pillar. So the back 1/2 of the panel is loose and ready to come off...
So far, so good but getting involved with the a-pillar corner has got me stuck where to make the cut as there is a brazed joint and the make up of the layers complicates things.
The basic options are:
1) below the brazed joint
2) at the brazed joint
3) above the brazed joint
But none are without some kind of problem.
The main complication is the outside of the a-pillar becomes the inside of the windscreen aperture in one pressing with the roof skin brazed in over the top last. I need to show you the way the structure is put together...
1st, the roof propped against the wall to help orientate the next pictures. You can see my rough inspection hole down the bottom which is where we're going next...
2nd, The inside of the a-pillar runs into the structure of the the door. You can see I have bent this away slightly to investigate...
3rd, A slightly more head on view to show the layers...
Yellow = Roof skin & outside of windscreen roof aperture.
Green x2 = Inside of windscreen roof aperture & outside of a-pillar.
Blue = Inside of a-pillar
Pink = Joggled fold
Black = Brazed? joint between roof skin and a-pillar.
So my take on the options is:
1) below the brazed joint
Good = The a-pillar is nice and strong to weld round (not going to warp) and its a short weld line too.
Bad = No good place to cut in due to that piece continuing over windscreen. Any cut on the car here would really affect the structure wouldn't it because you would need 2 cuts and then wouldn't have access to weld the upper cut? I don't really see how these guys did it...
2) at the brazed joint
Good = Would keep everything original and as intended.
Bad = I gather its not easy to separate a brazed joint and most people seem to recommend avoiding it. (unless you know otherwise?)
3) above the brazed joint
Good = Probably the simplest place to make the cut
Bad = Probably the riskiest as far as warping the roof panel.
This shows the position but has been overlapped with the old skin and joined with spots. Mine would need to be a continuous butt joint as I intend removing the old roof fully at the seams...
Phew that was long, my head is spinning LOL.
I *think* option 3 is the way to go but I haven't dared go any further because I'm not that sure either. I would love to hear your thoughts.
-Steve-
I'm changing the roof skin on my 924 to get rid of the leaky sunroof (and to learn). I haven't done anything like this before, I have got half way through un-stitching the donor skin and got a bit stuck in the windscreen corner. I have done some research and had a thorough look at it myself so I'm going to put a detailed description together, sorry if its a bit lengthy.
I have drilled out most of the spot welds on the 'new' roof section and have cut the weld lines where the skin is welded on over the c-pillar. So the back 1/2 of the panel is loose and ready to come off...
So far, so good but getting involved with the a-pillar corner has got me stuck where to make the cut as there is a brazed joint and the make up of the layers complicates things.
The basic options are:
1) below the brazed joint
2) at the brazed joint
3) above the brazed joint
But none are without some kind of problem.
The main complication is the outside of the a-pillar becomes the inside of the windscreen aperture in one pressing with the roof skin brazed in over the top last. I need to show you the way the structure is put together...
1st, the roof propped against the wall to help orientate the next pictures. You can see my rough inspection hole down the bottom which is where we're going next...
2nd, The inside of the a-pillar runs into the structure of the the door. You can see I have bent this away slightly to investigate...
3rd, A slightly more head on view to show the layers...
Yellow = Roof skin & outside of windscreen roof aperture.
Green x2 = Inside of windscreen roof aperture & outside of a-pillar.
Blue = Inside of a-pillar
Pink = Joggled fold
Black = Brazed? joint between roof skin and a-pillar.
So my take on the options is:
1) below the brazed joint
Good = The a-pillar is nice and strong to weld round (not going to warp) and its a short weld line too.
Bad = No good place to cut in due to that piece continuing over windscreen. Any cut on the car here would really affect the structure wouldn't it because you would need 2 cuts and then wouldn't have access to weld the upper cut? I don't really see how these guys did it...
2) at the brazed joint
Good = Would keep everything original and as intended.
Bad = I gather its not easy to separate a brazed joint and most people seem to recommend avoiding it. (unless you know otherwise?)
3) above the brazed joint
Good = Probably the simplest place to make the cut
Bad = Probably the riskiest as far as warping the roof panel.
This shows the position but has been overlapped with the old skin and joined with spots. Mine would need to be a continuous butt joint as I intend removing the old roof fully at the seams...
Phew that was long, my head is spinning LOL.
I *think* option 3 is the way to go but I haven't dared go any further because I'm not that sure either. I would love to hear your thoughts.
-Steve-