Replacing a mk1 golf roof skin

[daniboy1_2_3]

Hi there, im not sure this fits in here, although it is welding related, but im looking for advice on how to do this job properly. Ive been searching around on VW forums but i still havent found out any information on how to do this job as VW did. If there are any bodyshop workers who have done this job before id really appreciate their thoughts on how to go about this job without cutting the whole roof off or cutting straight down the gutters. I believe the VW procedure was to join it at the gutters. This would mean unfloding the old gutters and removing any spot welds that are in there which sounds like a tricky proposition. Look forward to hearing back from anyone clued up on this, thanks.

 

[steveo3002]

ive seen a couple done at the bodyshops ive worked at , assuming a mk1 is the same there will be spot welds in the gutter channe maybe hidden under sealerl , they will be hard to remove and reweld

you wont be unfolding the gutter and getting it back to look nice

 

[dannymac]

Do you have a new skin or are you taking one off a donor car?If its salvaging a donor,you could grind the spotwelds from under the gutter of the donor skin on easy access ones and drill from the top the welds on harder to reach ones,as you want to weaken the spotwelds without giving too much damaged on the skin side(less work when refitting).How I'd do it,remove windscreen,(3 door quarter windows)headlining and sunroof if its a tilt n slide and you can slice up and grind the original roof skin off but keep the cars gutters attatched and the ribs that are bonded to the skin(stanley knife will slice and peel the skin off those) and keep dressing and grinding untill youve removed the old roof from the existing gutters,which is what you'll puddle spotweld the 'new' skin on.Ive only done a couple,I brazed them on the pillars and spotwelded the gutters/lips under the screens(new skin from factory on 4 door cars).Heat warping is your major concern when youre putting it back on,a bit of dolly work will be needed,and a very sharp,thin chisel will save u alot of work.

 

[daniboy1_2_3]

Sorry for slow response. Unfortunately to remove the old roof in this manner would mean unfolding the gutters back to get the skin off. Ive been told that the chances of damaging the gutters by doing this are very high and there is a chance they will be ruined. Because of this it looks like the roof is going to have to be cut along its length either side, close in to the gutters before the new skin is welded in here. Its a long run of weld and im not sure exactly how the bodyshop are going to do it yet to minimise distortion. The spot welds will be drilled out around the windscreen and tailgate apetures.

 

[badersbus]

Cut down the length of the gutter rail leaving about 20mm of the original roof on the car and then use a joddle tool (air is best , but hand one can be done) to recieve the new roof that will sit in the joddle step. I have seen jobs where the edges are mig plugged through a 7mm hole every 100mm or so. This does give distortion but it is minimal if you use compressed air to immediately cool. The roof edge will still need remedial work for paint though.
If i was doing one now though i would structural bond adhesive the roof edges and carefully clamp until cured with this
http://www.bondtech.uk.com/cgi-bin/bonding/commerce.cgi?product=Automotive_Bonding&pid=13.htm
Front and rear apertures can be simply spot welded as per original.
Its not the easiest roof to change but can be done

 

[Springerdinger]

nice link badersbus just what I was looking for my roof skin
cheers

 

[daniboy1_2_3]

Ive heard of people using a product called cold front which is supposed to take heat away from the area being welded, not sure how effective this is though. Ive never looked into bonding a roof skin on but ive heard quite a few people mention it before. It would avoid any distortion that for sure. Would spot welding every 100mm along the skin cause that much distortion if you took your time?