--- In STMFC@..., Anthony Thompson <thompson@s...> wrote:

A.T. Kott said:
...It was my understanding from

somewhere that "cast steel wheels" suffered from the same cracking
problems until just prior to WWII. At that time, foundries

figured

out how to design and cool them properly so that they were not

prone

to cracks.

I doubt this story very much. Cast steel sideframes for

freight

and passenger trucks were being marketed shortly after 1900, and

were

entirely competent castings by 1920. The same is true, after all,

for

locomotive frame components, drivers, cylinders, and other large

and

critical steel castings....

Tony - Thanks for the response - always wondered how the "wrot stl
whls" were made!

I agree that steel wheels should have been in use earlier,
considering the other, more complicated castings were perfected years
before. Do you have any opinion as to why cast steel wheels were not
used prior to the late 1930's in any quantity? Also, were passenger
car wheels during the 1920's and later made of cast steel or of
wrought steel? Perhaps the rr's had a bad experience with early
trials of cast steel wheels on heavier (than pass. car) freight
cars. Also, the rolling weight at the tread may have caused problems
with work hardening in the earlier steel alloys, causing shelling out
of the tread area.

One last question - what is that honkin' big hole for in the hub on
the backside of the typical chilled iron wheel? They were not pinned
to the axle! Was the hole necessary because of the steel axle/iron
wheel press fit?

Thanks again! I love this board!! I love freight cars!!

A.T. Kott