Electric Sunroof

The first extra to be fitted is a sunroof. I have a Golde fabric sunroof in my Beetle and had an aftermarket sunroof in my original Variant, so had come to love the feeling of fresh air. Fitting a sunroof in this car meant cutting a large hole in the roof and other work welding brackets into the roof, so I needed to fit this before finishing the preparation work for painting.

After looking around I found a nice glass tilt and slide electric sliding sunroof in a local scrap yard in Derby which I reckoned would fit. It was from a Rover 620 which had met an untimely end. The tricky bit about transplanting a sunroof is getting the hole in the right place – and the easy way to get that right is to use the old hole as a template. And the next tricky bit is to get the mounting points for the mechanism in the right place. So I agreed with the yard owner to cut the whole roof off at the tops of the six pillars. I then collected it and tied it onto my roof for the journey to Kent.
We survived the journey down to Kent and here it is, propped up in the barn.
The first thing to do is to remove the mechanism from the roof, leaving the mounting points and the reinforcement around the sunroof opening.
Then I started trimming the unwanted metal – the first to go was the roof edges, the tops of the door frames. The inner lining is now visible and it stops short of the back of the roof (to the right in this picture).
So I chopped the roof behind the lining ... ... 
 ... ... and try a first tentative fitting inside the Variant.
What I’m looking for here is a good snug fit to the roof around the opening.
I then needed to transfer the setting out measurements to the top of the roof – I have started to mark out a few scribed lines in the paintwork here. The most important line is the centre line, everything else depends on that being right.
Having got thus far I realised that I had forgotten to allow space for the sunvisors! These need to fold up flush without obstructing the sunroof opening and there is a recess in the Rover’s roof lining for them. When I checked this as a setting out point, I found that I had set the roof frame too far forward. Having investigated further, I also realised that the hole in the lining was set back behind the hole in the roof to allow for the mechanism. It’s just as well I had time for reflection before I made my cut!
Having checked again, I marked up the correct position for the roof opening. Then I needed to transfer this setting to the outside – here I have drilled a small hole to do just that.
I then placed the incoming hole on top, carefully aligning the centre lines. By rocking the roof from side to side, I could mark around the opening with a felt-tipped pen.
I then placed masking tape around the outside of this line to help me see it during cutting and to act as a witness to my accuracy.
Then it was time to get brave again! Here I have started the first cut across the back with the air saw.
I needed a small drilled hole along each side to start each cut but the air saw wouldn’t go round the corners. Here I needed my nibbler.
And here we are with my new sunroof! At least, a hole to take my new sunroof!
Here is the frame offered up again to the underside to check for fit.
The centre lines lined up precisely ...

This first cut was the same size as the sunroof opening – to double check the position and general fit.
I had decided to set the new rim into the existing roof by a narrow lap around the edge. I needed to trim around the donor roof aperture so I marked this out with masking tape as here.
Here is one of the front corners after trimming to the edge of the tape. My intention was to leave a 20 mm lip around the hole and to trim the existing roof 10 mm larger all round. That would allow me just enough to shuffle the frame into place and give a 10 mm overlap on the joggle.
I also needed to reattach the mounting point for the roof switches and interior light. Another change of heart during my time of reflection during my winter break.
A trial fit to check the position and clearances. Then the final size for the trim could be marked and the initial hole enlarged to take the lap.
A view of Goldie’s interior. The sunroof switch and light unit needs to fit into this gap between the visors, just behind the rear view mirror.
The enlarged hole, checking for equal distances all round.
Then I formed a joggle all around the edge of the hole. After taking this photograph, I sprayed round the bared metal with a zinc-rich primer. I have joggled the existing roof down so that the incoming frame will sit on top of the parent metal and be self supporting whilst I make the welds.
Then shuffled the new frame into place ...
... and welded all round, followed by another spray of zinc-rich primer. The heat of the weld has pulled the seam downwards slightly meaning it will take a thin run of filler to make it invisible later.
A low level sight to check the flush fit and how well the general shape had come together. I have had to temporarily prop the centre of the roof here as it is quite flexible with none of the stiffening put back in yet. The front nearest the camera is stiff enough because of the double curvature.

The next step is to fill the join, here I have applied the first layers and it needs to harden off before I can start to blend it in.

But before that I need to stiffen up the roof by bracing the inner skin to the top rails. Below is a view of what I have along this line. To the rear (left in this view) is one of the original (black painted) stiffeners which fits in between the outer roof and in new inner frame.

 
Here I have screwed the stiffener to the sides and have pulled the inner lining tight to the stiffener with more screws.
The sunroof mechanism is installed to check the fit. I can already see I shall have to adjust the angle of the interior light frame – I have lost a couple of inches headroom! Fortunately the Type 4 is generous so I hope I won’t miss this.

But the important check is the fit on top – is the glass roof flush with the steelwork?

Unfortunately not – the front is acceptable but the back edge is slightly low.

I would have to remove the inserted stiffener and relocate it slightly further back as can be seen here. The wire hanging down is a temporary connection to a battery to enable me to drive the roof back and forth to check all was well with the fit.
I would then have to lift the lining before welding in my bracing pieces. Here you can see the timber prop with which I have pushed up the liner and I have attached the first brace.
Two more braces added adjacent to the roof mounting bolts complete this side.
I preloaded each of the braces with the long jaw G-clamp before welding the lower edge – this view is of the opposite side of the car.
After removing the mechanism, the relocated stiffener is visible across the back edge of the liner. I have welded this to the sides and have pulled the liner up tight to the stiffener with more screws. The remaining stiffeners will go back in later after painting.
The proof of the pudding – the back edge is now just proud of the roof surround. It’s a bit difficult to see in this view but ...
Another view of the fitted mechanism with the roof tilted forward. This fitment has taken a lot of time and effort but I think it has been well worth it.

The final finishing to bring the welded joint completely flush with the surrounding roofline took several hours and couldn’t be rushed, but I was pleased with the final result.
A view of the roof after finally finishing off the filling and rubbing down and a spray over with zinc-rich primer. Hopefully, an invisible joint ...
... as can be seen in this view which shows off the newly finished paint work quite nicely.
A view of the sunroof mechanism installed into the car.
The next job was to fit the drain tubes. These had to be threaded through the hollow pillars to lead any water getting past the sunroof seal away so that it would not cause internal corrosion to the car’s bodywork. I had to find a plastic tube that was flexible enough to negotiate the route through the hollow sections but stiff enough to not flatten in the hidden corners and so become blocked. After a long search and several puzzled motor factors, I eventually settled upon an 8mm diameter braided PVC compressed air hose from Machine Mart priced at £9.39 for a 10 metre length.
The front was easy, I simply threaded the tube through the A-pillar, out through a newly drilled hole just below the windscreen, and through another newly drilled hole and down the front of the car. The end is secured where it will not drip on the bodywork or suspension.
The rear was more tricky, there was no direct route as for the front. This picture is of the tube connected to the spigot on the sunroof mechanism and disappearing into the hollow section above the rear door pillar.
And here it can be seen emerging below the side window and following the line around the inner rear wing to its discharge point. Due to various obstructions, it would not go down the door pillar and I had to thread it down the original mid-pillar where the seat belt mounting point is situated. Not an easy task! The end will emerge safely (and invisibly) beneath the outer wing when fitted.

Now all I have to do is to connect up the wiring ...