Webasto sliding roof (69, 78)
Mercedes Typ 219, "Ponton", 1956 - 1959. Zeichnung aus einem Prospekt von 1957. © Daimler AG
Do also have a look at Chassis-Welding around the process for installing the Webasto roof frame in the car. My sliding roof is said to be the first version of the type. Below you can see a photo of a later frame from Thomas Hanna (Ponton Manufaktur in München). How much it differs when it comes to the assembly I don't know.
When everything was ready for the assembly including having a dedicated saddler in place I tried to order the complete sunroof with pre-sewn headliner and cover from the company that had provided me with samples (Note 1: some call the cover for "skin" or "canvas", GAHH calls the cover for "topping", no idea if that is more correct but I stick to the Spare parts list word "cover". Note 2: the cover is supposed to have a "plastic" look, not the "woven" look of cabriolet top fabric!). The company however had disappeared from the surface of the earth… No contact via phone or mail or even trying to make a personal visit by a friend yielded nothing.
Finally I switched to Himmelservice Ingrid Oppermann and got samples that I accepted. I was a bit concerned about the headliner material. It didn't look as "rough" as it should be for a sunroof car. But according to them it was the correct one for this roof so I placed the order. It later turned out, when I placed an extra order for fabric for the sun visors (which are supposed to have the same fabric as the headliner of normal, none-sunroof, headliner), that they only had one type of fabric. Well, the difference is probably not that huge but it is indeed annoying. We also had problems sourcing the correct and color matching vinyl which is needed for e.g. the dash but suddenly the first company, which previously had vanished from earth, popped up again and could deliver it.
The process of assembling the sunroof is well documented in the workshop manual and also in a Mercedes-Benz Ponton page's restoration article as well as in a couple of articles in Mercedes Pontonology. But these sources don't explain why I have two sets of three holes in the rear part of the Webasto frame. There is a vertical slot marked in the first picture as well. That one is for adjusting the rear sheet metal cover. In the second picture you have a threaded hole in the vertical part of the frame. that is for the screw that locks the wire that tightens the edges of the outer skin of the sun roof..
Neither did they give me and my saddler full understanding of how to tighten the wire with the two screws in the rear, both in terms of how the wire should be drawn down from the rear plate (without damaging the metal plate, that fixates the wire there due to the downward force when the wire is tightened) to the screw but also the function of the locking mechanism. Spinning a wire around a screw and then drag it diagonally outwards ought to result in a loose wire, sooner or later...
Maybe the reason is that I have an early, maybe unusual type of frame. I don't know how many phone calls and e-mails I made and sent to persons and companies in Europe and USA. One of the persons I harassed was Arne Malm (a Benz legend) who - from more or less the beginning - gave an in-depth explanation. But it's hard to really understand and follow if you cannot see it in real life on a car or in good pictures. So it took me some time to verify this so that both me and my saddler were fully convinced of the process, the do's and don'ts. Thanks to Fritz Bernats (owner of Bernats Bil and another Benz legend in Sweden) I came in contact with Holger Merker Autosattler in Hamburg. After a couple of phone calls, e-mails and a set of pictures I finally understood Arne's description. Also Thomas Hanna and his saddler Armin Sturm in Eching/München gave me invaluable help forward.
First I describe the two sets of three screws. Those are intended for two, lengthwise ribbons, made of the same material as the sunroof's cover. These ribbons have two purposes, a light, hold-down pressure on the bows and also taking up the traction force when the roof is closed, reliving the cover (maybe also the headliner). The width of the ribbons equals the width of the three holes plus one or two centimeters (equaling 12-15 cm). The ribbons are fixated in the rear by screws in these two sets of holes, and laid out over the bows and finally screwed on top of the locking bow and locked by the front aluminum sheet cover that is assembled on top of it. The ribbons are also fixed in the gliding bows with screws, but not in the folding bows. The ribbons do not go on top of the aluminum cover or further down on the front - or under - the locking bow because then they would be visible. After that you glue felt on top of the bows in order to protect the cover as well as to minimize the visibility of the ribbons from the outside.
Then we come to the wire. The wire is fixed in the frontal sheet metal cover and runs backward, along the sunroof's outer edges, holding down the sunroof cover against the roof, making it water proof. At the rear it makes a U-turn in a "channel" under the rear sheet metal cover, being hold in place by a metal plate. The wire is supposed to be able to glide in this channel. So, how to you assemble it? Well, close the sunroof, with the wires loose. Tighten up the cover with help of the rear sheet metal cover (see the second last picture which shows the adjustment mechanism) and its adjustment screws, almost so that you cannot close the sunroof. After that you tighten the wire, not too hard, not too loose. Do it with some feeling :).
Then you drag the wire down to the screw at the rear of the inside of the frame, between two washers and tighten the screws (the last picture). Done. As I said above, in my opinion this solution should damage the metal plate under the rear sheet metal cover, the wire wouldn't be able to glide in this channel and the solution for locking the wire shouldn't be able to hold the stretched wire for long. But all the saddlers I've spoken to say that that's how it should be and none of my imagined problems ought to occur. So my saddler did as told and he was actually satisfied with the result and thinks it should work. Well, we'll see...
And then the "easy" part...
Unfortunately I don't have as many photos of the assembly as I would have liked, damaged SD card in my saddlers camera. But I hope I've been able to give you a better understanding of my two issues. The rest goes according to the instructions I mentioned above.
Furthermore, before the headliner etc was installed the roof was sound proofed with help of Dynamat. Also,according to Arne Malm, the weather strips along the headliner should be cloth above the bakelite frames of the doors and color fitted leather beneath, as with detailing of the B-pillars. I haven't seen any pictures of this but I'm sure he's correct. We however, went with the material sent by Himmelservice, cloth.
Since there is no drainage in the frame we rust protected it thoroughly. Even if the sunroof doesn't let water in (it was sprayed with a hose to test), there will always be the risk for moisture.
Below comes some diverse pictures from the assembly. As usual, see the pictures' title texts for information about what parts you're seeing.
=> The gallery above is only an excerpt. More pictures of the assembly of the Webasto sun roof can be found in article More Webasto sliding roof assembly pictures.
Bought from Thomas Hanna. Fantastic looking thing but hopelessly complicating thing whenever you want to open the sunroof.
See also the related article Sun visors, straps.
And then transport back to the garage (small, yes I know, but a bit closer to home..). Again... But I like this type of picture since it marks a milestone in the restoration process.
If you're interested in all the details of how the parts looked from the beginning you can go through the following pictures. As usual, see the pictures' title texts for information about what parts you're seeing.
Note that the locking bow you can see here is not the one I installed. It was in a too bad shape. See chapter "Sliding roof" in the article Welding regarding how I found a new one :)!
=> The gallery above is only an excerpt. More pictures of the old parts can be found in article More pictures of the old Webasto sliding roof.