Hi Andrew
On (03 Jul 97) Andrew Hamblyn wrote to Alec Cameron...
AC>  GP> The newest NZR loco is 30 years old........
 AH> ahhhhhhh
 AH> sorry but our DF class loco's, built by GMDD in Canada, were bought new 
in
 AH> 1979-1980, making them just under 20 years old, and our EF electric 
locos,
I offer no defence, the 30 years comment was NOT mine.
AC> A serious loss of adhesion for a steam loco, may be the "shimmying"
 AH> effect 
AC> the loco sways left, right, left with the reaction to the horizontal
 AH> forces
AC> the piston rods. This must be a real dance routine for Beyer Garretts
 AH> and
AC> other locos having two asynchronous engines beneath the boiler. At one
 AH> stag
AC> the pistons moving in synchronism [jazz waltz] and minutes later the
 AH> front
AC> piston flying backward while its partner on the same side is flying
 AH> forward
 AH> ummm.. we also have a Beyer Garret imported from S.A, which has been 
 AH> restored,  when she lets go there is nothing but noise and sparks from
 AH> wheels..... We have had no problems with your sideways dance you
 AH> describe...
 AH>                                                   
 AH> please think on these....
I have thought, and I recall conversations with my wife's Uncle Cec who was a
loco driver until c1950. He was an animated, demonstrative guy and by dancing
on the spot [like a well fed bee communicating the nectar source] he 
xplained
that he was always amused to stand with one foot on the engine footplate and
the other on the tender. The one oscillating in the vertical plane and the
other in the horizontal plane.
You might try this!! His fireman would have little chance of rest, Unc Cec 
as
a lively midget.   Cheers.....ALEC
...         Me drive? I'll take the train as the good Lord intended!  ^oo   
oo^oo   oo^
--- PPoint 1.92
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