[N&W] Re: What if?...

[nw-mailing-list at nwhs.org]

[Gary Rolih wrote:]
 >A good description of Franklin and the poppet valves can be found in Vernon
 >K. Smith's autobiography "Locomotives in My Life" ( I hope I got that
 >right!) now out of print.  Smith worked for Franklin during the
 >introduction of the product.  Note that the C&O put the poppet valve gear
 >on a some of their 4-6-4's in the much simplified worm drive version.

[Ed King responds:]
Smith is an unabashed and unapologetic advocate of poppet valves.  He was my
neighbor before I retired and moved south, and we had many conversations
over coffee at his place and mine (I took advantage of the opportunity to
have him sign my copy of his book - One Man's Locomotives).  He had one of
the most fascinating and varied careers of any railroader I ever met, and is
a terrific conversationalist.  He is also a live steam modeler, and he's
test run his Egyptian Railways 2-2-2 express engine - it's inside connected
with Stephenson valve gear - in O-scale, yet.

 >The original Franklin design as used by PRR used a complex gearbox and cam
 >system mounted to the front of the engine.  The system wasn't very
 >accessible for maintenance and required special maintenance training to set
 >the system up correctly.  This design had a lot of parts and was costly to
 >manufacture.
 >
 >Gary Rolih

This design used a combination of Walschaerts and Young valve gear in a
box - all the motion was taken from a small union link and a lever on each
engine, and the lever on one side drove the valves on the other side.
Smith's book has a diagram of this arrangement.  The boxes were hard to
reach and maintain.

EdKing

 >____________________________________________________
 >Nathan,
 >
 >      One of the best sources of general information on poppet valve
 >locomotives and what improvements could be expected can be found in Vernon
 >Smith's book One Man's Locomotives, Trans Anglo Books, 1987, pgs 61-85 and
 >pgs 100-104.  It contains his personal experiences and opinions regarding
 >the application of poppet valves to many different locomotives.
 > There was no time left to work out the
 >bugs.  PRR succeeded in getting many of them out of its T1s through late
 >modifications.  But IMHO, N&W took the right approach by sticking with
 >mechanical simplicity and sophisticated operation to move its traffic.
 >
 >Dave Stephenson

Smith did considerable work on the T1 in the field, as well as on "his" ATSF
3752, the Burlington 4-8-4 and others.  He makes the case for the T1, with
no little validity, that the T1 took its place in a very demanding operating
environment and did its part for several years before diesels came with no
apologies to anyone in spite of its publicized drawbacks.  And one wonders
if a lot of the bad publicity about the T1 came from crews miffed about the
engines replacing the old reliable K4s - and their crews - on a 1 for 2
basis.  See "Second Engine No. 28", May, 1975 TRAINS, by John Crosby - one
of the best stories TRAINS ever ran.

EdKing

 >____________________________________________________
<snip>
 >Rigid wheelbase longer ( 3 ft. ) than a conventional 4-8-4; increased valve
 >maintenance; and potential for drivers slipping at speed.  One suggestion,
 >rejected by PRR, was for driver sets having different diameters, so that the
 >two sets would not rotate in sync.
 >
 >Jerry Crosson

Keep in mind that the B&O 4-4-4-4 duplex, nominally with 76" drivers, had
one set of drivers turned down so that they would not get into sync.


Oh, and I forgot to mention - It's Vernon L. Smith.

EdK