Question on pre-war cars..

[cobravii]

Ok, at the risk of exposing myself as a total newbie.....

Why do a lot of the pre-war closed in cars have a square missing out of the centre of the roof and then have a fabric roof inset??

Why didn't they have a full metal roof? :confused::confused:

[1939_Buick]

Construction & fabrication methods / machines were not capable of pressing the roof. Was only about 1937 that heavey press's had that abilty. The thickness & type of metal also effected the abilty to press the roof.

[Dandy Dave]

We did not have the Technology until 1934.... The stamping dies were extremly expensive. This was a real mile stone in automotive advancement.

Also, The last 3 months of production on a 1931 Model A Ford truck, the roof was all steel, but was in two pieces if my memory serves me right. Dandy Dave!

1934, The First One-Piece All-Steel Roof - Generations of GM

[Restorer32]

The first all steel roof stampings were developed by York Hoover Body Company in York, PA. It was a combination of larger presses and better, more formable steel that made it possible. York Hoover was experimenting with stamping 1 piece steel caskets at the same time.

[Rusty_OToole]

One thing that held them back was the available steel. The steel mills did not start making sheet metal wide enough for a whole roof until 1934.

Until then the body had to be made of smaller pieces welded together. For example, the 1936 Cord sedan had a roof made of seven pieces, welded together and the seams filled with lead body solder then filed and sanded smooth by hand. This was a very expensive car. Some custom body Packards made before 1934 had a solid roof made in a similar way.

For cheaper cars the roof was made of smaller pieces welded together leaving a hole in the middle. This meant only a few inches of seams to be filled.

The center of the roof was filled with a waterproof material or heavy oilcloth over a padded wooden frame.

This question has been answered before, I recall one thread on the Dodge board.

Basically it was a matter of working with the available sheet steel in the best most economical manner. Even after the wide steel became available it took a while before all manufacturers invested in new giant presses big enough to stamp out a whole roof in one piece. Cheaper Plymouths had a fabric roof insert as late as 1937. More expensive Plymouths had the same hole but filled with a steel insert.