Rail codes

[steve howe]

Can anyone enlighten me on the relationship of rail codes to the weight per yard of the real thing? Does, for instance Code 55 rail relate to 55lb per yard? My current project uses Code 60 FB rail, and I am just intrigued as to the correlation between the codes and the actual rail weight.

Steve

[Noel]

There is no correlation. Model rail codes relate to the height of the rail in thousands of an inch. Code 55 is 0.055" nominally [different batches may vary slightly] and would be for N gauge usually, although it can be used for a lightweight section in 4mm. Full size rail height is not necessarily higher for greater weight per yard; it depends on the cross-section shape, so that rail with similar weight per yard may be of different heights, and conversely rail of the similar heights may be of different weights. The real railways use, or have used, many different profiles and weights for their rails; model rails are each basically a generally acceptable compromise for a number of real rail profiles, for cost of production reasons [or else just designed to cope with the size of overscale flanges used by different manufacturers].

[grovenor-2685]

As the rail code represents only the height the other key variables can be well off, especially when using a rail in a scale it was not intended for. From a model viewpoint head width is important for correct appearance and foot width also to some extent. for the prototype drawing may be locatable, for the model you have to get a sample and measure it.
Kargarin has provided some dimensions here, https://www.google.com/url?sa=t&rct=j&q=&esrc=s&source=web&cd=3&ved=2ahUKEwiG-4iy2ezjAhWBSEEAHXTjC-kQjBAwAnoECAgQCw&url=http%3A%2F%2Fwww.karlgarin.com%2Frail_flatbottom_sizes.pdf&usg=AOvVaw3l6xbBJdA6vumniTcPlIqq
I have data for quite a range of sizes as used by Rhodesia Railways/Zambia railways if you need more.
Rgds

[grovenor-2685]

Just to follow up on this, my drawing of Rhodesia Railways sections includes 14 varieties and I have summarised the key dimensions in the attached pdf. Also attached are 3 scans from the drawing. (some sections are to faded to scan adequately). Note the BS80LB A is the same rail used for the Docklands Light Railway.

RR rail sections.pdf

60lb flat top.jpg

60lb BSS.jpg

BS 80lbA.jpg

BS80A Scan.jpg

[FCA]

Out of interest I attach an image of a sample section of Southern Railway 95lb bullhead

IMG_1941.JPG