The Truth about the Walschaert Valve Gear...

[joegideon]

Bach Man!  You  guys make TRAINS!  Back when the 2-10-2 arrived, I noticed that the catalog blurb indicated a variety of valve gear, depending upon the prototype: Either Southern gear or Walschaert gear.  None of the 2-10-2s has Walschaert V.G.  All are equipped with Southern gear, except  for the S.A.L. version- which has a Baker V.G.  Similar- but definitely different- and in their day- competing products.
I guess I (sorta...)understand how that could happen- but a year later the phantom Walschaert gear showed up on your Spectrum 4-4-0.  Not even close, folks.  The 4-4-0s- all of 'em- have Stephenson gear, located between the frame rails(-and therefore ALMOST invisible).  Walschaert gear, while not exactly a modern valve gear(-it was used on the 1860s-70s Mason Bogies-), didn't really appear on many locos until after the turn of the century.  Probably 85% of the steamers- and 95% of the larger steamers-  made after 1900 had either Walschaert or Baker gear.  The largest use of Southern gear was on the USRA 2-10-2s and on the Southern Railway's engines.  The major spotting difference is the lack of the forward link(-the vertical rod that is connected to the crosshead)on the Southern. This function was handled by one of the two links located at the valve gear hanger. The Baker gear had an upside-down 'V'- or 'U'- shaped link at the hanger. 

I used to wonder why little things like this seemed to rattle the cages of certain poor saps... As I recall, 'rivet counters' rings a bell... But you really should correct these items.  Bachmann has pretty-well shed its image of being makers of mediocre toy trains... so it would seem to me to be in its better interest to appear as if it knew what it was, uh... doing.

...two, three, four, fi...   

[wjstix]

I'm gonna bet on the Bach Man on this one. Remember that there were more USRA copies than original USRA engines, and the copies had more variations. Even if original 2-10-2's didn't have a particular valve gear etc. doesn't mean later copies didn't.

4-4-0's c. 1880 certainly would have Stephenson valve gear...but some of those engines ran into the 1940's and had many changes over the years. I believe a few 4-4-0's were even built in the 1900's BTW. I've certainly seen pics of 4-4-0's with what appears to be Walschaert valve gear from say the Twenties or Thirties, late in their careers.

[nickco201]

  Well I agree to a point about the 2-10-2s.... however there were MANY variations....
  ET&WNC never had any 4-4-0s.... except during the 1800s when a small stretch of the road was built as broad gauge and they borrowed a 4-4-0 to use as work train power then it was rebuilt later into narrow gauge....
   ET&WNC 4-6-0s were all built new circi 1910-1919 or so with walcheart except the first #8 which had stephension.
   The photos of the 4-4-0s Richmonds on the Bman  website all show stephension, and all the 4-6-0s show walcheart. Converting the 4-6-0 to stephension would be a extremely simple process.   Not very many 4-4-0s had walscheart...
   The thing I would love to see would be Southern gear on the 2-8-0s....
   One thing that is funny is that most Southern Ps-4s, and Ms-4s were built with baker then changed to walscheart later on....just shows that it all has to do with where a loco was shopped. 
  On the 7.5 inch gauge coal fired live steam PS-4 I am building I chose baker.... there is very little to wear out!
   - Andrew

[ta152h0]

I found this, and it is so cool
http://home.new.rr.com/trumpetb/loco/rodsr.html

[ebtnut]

There were some 4-4-0's built with Walschearts gear in the early part of the 20th Century.  The most prominent were probably the Chicago & Illinois Midland locos.  If you track down the pics of the forth-coming outside-frame On30 4-4-0 on that forum, you will see that its prototype also had Walschearts gear.  The Walschearts gear dates back to the 1880's, but did not find wide acceptance until after 1900 in the U.S.  It likely became the most popular valve gear in the time from 1900 until the end of steam.  Baker was probably second, and that may be because it was a proprietary design.  The Stephenson gear was reportedly a very good valve gear.  But becuse it was internally mounted, it became a maintenance headache as locos got bigger and there was less room to work.  There were a few cases where Stephenson gear was mounted outboard, but that was very rare.