And cast iron brake shoes threw many sparks, necessitation "spark shields"
under wood floors

Tom Birkett



From: STMFC@... [mailto:STMFC@...] On Behalf Of
Anthony Thompson
Sent: Tuesday, May 15, 2012 2:12 PM
To: STMFC@...
Subject: Re: [STMFC] Re: Turn of the century freight car wheels





Dennis S. wrote:

The biggest disadvantage of cast iron wheels was that the uneven
heating from heavy tread braking (this being before the days of
dynamic brakes) could cause cracks to develop in the wheel flange.
If a portion of the flange broke out, it could lead to a derailment.

The same thing can and does happen with wrought steel wheels
under heavy braking, even in the diesel era.

Tony Thompson Editor, Signature Press, Berkeley, CA
2906 Forest Ave., Berkeley, CA 94705 www.signaturepress.com
(510) 540-6538; fax, (510) 540-1937; e-mail, thompson@...
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Publishers of books on railroad history