On 7 Dec, 13:49, Roland Perry wrote:
In message , at 12:19:45 on Fri, 7 Dec
2012, remarked:

Have you done any sums to figure out how much de-icing fluid would be
needed? *And have you ever tried clearing ice off your car's windows
with just a brush? *No, you need rather more than just a brush.

If I was brushing it all night it wouldn't frost up in the first place.

Of course it would. The remaining moisture in the air would frost the
window in between brush strokes (which are only any good at clearing
snow, not frost and ice). Unless you are pouring de-icer continuously,
and one of the drawbacks of de-icer is that the alcohols evaporate and
make the glass even colder than ambient.

IIRC, TfL's predecessors used to coat the conductor rail with some
sort of grease during the cold season. The conductor did not ice
over. Arcing was much reduced.

On Fri, 7 Dec 2012 07:29:04 -0800 (PST), 77002
wrote:

On 7 Dec, 13:49, Roland Perry wrote:
In message , at 12:19:45 on Fri, 7 Dec
2012, remarked:

Have you done any sums to figure out how much de-icing fluid would be
needed? *And have you ever tried clearing ice off your car's windows
with just a brush? *No, you need rather more than just a brush.

If I was brushing it all night it wouldn't frost up in the first place.

Of course it would. The remaining moisture in the air would frost the
window in between brush strokes (which are only any good at clearing
snow, not frost and ice). Unless you are pouring de-icer continuously,
and one of the drawbacks of de-icer is that the alcohols evaporate and
make the glass even colder than ambient.

IIRC, TfL's predecessors used to coat the conductor rail with some
sort of grease during the cold season. The conductor did not ice
over. Arcing was much reduced.

You might be confusing de-icing fluid with Sandite used on running
rails. De-icing fluid used to be similar to dilute car anti-freeze but
has been replaced by newer stuff which does not wash off as easily and
is claimed to be "greener" :-
http://www.arrowvale.co.uk/component/content/article/61