Thanks for the technical details Earl. A retired D&RGW engineer (deceased now) gave me lots of stories and details about operating a flanger or spreader (for my snow fighting book). He said that an engineer really needed to know the line to know when to raise the flanger blade. The D&RGW and RGS actually took up some road crossings in the winter as there were not many cars and the road were not plowed. I have an RGS memo where they talk about actually taking out little used switches in the winter to lessen the chance of a flanger taking one out. He said that it was fairly common to wreck a flanger blade at least once a winter. He told of an engineer who forgot to raise the flanger on Rotary OO and tore it off at a road crossing on the Crested Butte branch.