Why didn't MB use aluminum for hard tops??
 

As most all SL owners will attest, these hard tops are heavy! I wonder why MB didn't use the much lighter aluminum instead of heavy steel? It's use would have made not only removal and installation much easier, but would have made the car lighter and faster too!
Any comments?

The steel top would survive a rollover far better than an aluminum one.

alum
 

According to my window sticker mine is aluminum

Anddddd the soft top, how did that perform?

Seems having an aluminum hard top would be safer than a canvas soft top with flimsy soft top frame when compared!

alum top
 

The R129 are equiped with an automatic roll bar system that works regardless of the top of lack off, much earlier models like the 1955 to 1964 190 SL came with an aluminum hard top as an option, the doors, hood and trunk lid were also aluminum ,thats pre lawsuit era convertibles.

It may not have mattered. The car already weighs in at over 4K lbs...

The History Channel recently showed a special on the German Autobahn and the camera system they use to monitor traffic. One of the clips was of a night roll-over accident involving an SL, a 107. The driver lost control at high speed. The car, with hardtop, flipped onto its top, slid and rolled over several times into the ditch landing on its top. A few seconds later the driver and passenger opened their doors and crawled out, dusted themselves off and sat down to await the arrival of the cops.

I think that is why MB made the 107 tops the way they did...

FWIW,

230/8

Don't forget the rollbar ...soft or hard top-it's always there.

Aluminum use in hard top
 

I might throw out a guess. It may be due to the thermal expansion of alum was a consideration for a material. It gets too hot and too cold - tough to seal under expanding conditions - this is 1970s design do not forget.

I wonder if fiberglass could have been an option too, and with a roll bar integrated. I suppose in the end product, overall weight saved would amount to little gain, so steal was a practical way to go for MB, I assume?

Remember the 107 first hit the streets in late-1970 and early-1971. Presumably Aluminium was too difficult/expensive. Weight saving then had not become the issue it is now. On the 129, first issued in mid- to late-1989, but signed off as a design by 1986, aluminium was used specifically to address the problem posed by the weight of the top on its predecessor. Of course, the panoramic top available from 1985 is incredibly heavy! On the new 230 many of the body panels are aluminium.

---Not to mention the spotwelding dilemma. Aluminum tends to stick to spot welding electrodes, building up an ever-resistant layer of crud on the tips. Regular cleaning of the weld electrodes would be required, and the weld strength would not be predictable. Newer alloys now may have solved this problem, but back then it might have been a consideration.

Around the late 70's GM and one of the big Aluminum companies got together to do a feasibility study of an aluminum-bodied Vette. The project was abandoned mainly due to the above reason.

hard top
 

I was part of a restoration on a 1957 190 SL this vehicle was strip to the bare metal including the hard top wich it was aluminum, this top was a 2 piece and believe it or not, the parts were welded together and impresive feat of engineering for the time, no filler no warp no putty, a 1/4" weld seam across the center from side to side, needless to say this was 20 years ago and ever since then I have always admire Mercedes Engineering.There must be a good reason for the steel hard tops, structural maybe.

Maybe, but one thing is for sure, it makes the car more top heavy, and I do feel a difference without it on. I prefer to have it off! :rolleyes: