Lightsteel Coach Question


Guerbetaler
 

Am 07.05.2021 um 06:43 schrieb csipromo via groups.io:
Can anybody explain why there are so many differences in the design
of the doors between the A, AB, B and B (middle entrance) coaches?
This was the consequence of a long development between 1935 and 1953. The first coaches appeared with old-type doors in one piece but they had either to be put far back in a recess or then they violated the loading gauge when open. With no automatic door closing available it was a necessity that a train could pull off with open doors. The first coach, which had a large recess, and all luggage vans kept this type of doors.

The first approach for a better solution was sliding doors but they were abandoned as not reliable. Next development was the folding door with wings. Exactly said the doors had two wings that were connected but the wings folded, when the wings were opened. A door had four parts. This was later reduced to three parts, having one wing that didn't fold.

It required some testing with the opening mechanism, because the task of opening doors was left to the passenger. One test was with long levers inside that actuated the doors indirectly. Finally the handle directly at the door was the solution retained.

Not all coaches have the same number of small windows in the doors. Doors made from four parts had two windows in the middle. Doors with three parts had three windows but some exceptions only had two. To make it interesting it wasn't always the same part that came without window.

Coaches with single doors (instead of the double doors) allowed a new construction with only two wings but no folding. This design was developed into what became the Einheitswagen doors.

Last development was the center entrance coaches with double doors.They had folding doors but no wings. The number of parts was also reduced to only two.

Markus


csipromo
 

Thank you very much for clearing that up.

Regards

Mike C


Guerbetaler
 

I have uploaded a little drawing of the four basic types of doors on light steel coaches. I have to add that the end position of the folded wings wasn't the same on all coaches. Only photos can say how it was on a deratain coach. The drawing only shows the basic principle.

/SBB/folding-wing-door.jpg

Markus, G├╝rbetal