Santa Fe training video: How to Operate a Steam Locomotive

[Jones1945]

 

 

 

 

 

 

 

 

 

 

 

A Santa Fe training videos dubbed by Coalition for Sustainable Rail, featuring Santa Fe 4-6-4 #3464 operated at 93mph plus lots of detail on steam engine operation.

The engine accelerated much faster than I imagine after start-up, though the video doesn't show how many cars were behind her (there was none at 00:22 but some coaches at 04:42). I wish I could operate the reversing lever of the power reverse (a Ragonnet power gear?) and find out how heavy it was.

 

[Overmod]

Jones1945

I wish I could operate the reversing lever of the power reverse (a Ragonnet power gear?) and find out how heavy it was.

Not heavy at all.  Full lock-to-lock forward to reverse excursion can take place in a matter of one to two seconds if commanded, with controlled servo stopping of the inertia of the moving parts at any particular position.  There is no explicit 'force feedback' of the system inertias, much as in the controllers for the Huletts we discussed a while back.  Rack notches are not to hold the system against force, as in a Johnson-bar arrangement; they are for fine position holding in the relative absence of friction in the hand control.

The 1940s adoption of proportional air throttle control was in part designed to give this kind of stepless proportional control to a multiple-poppet throttle valve, which otherwise has mechanical loss of proportional control opening the first poppet and then in the ranges around progressive initial unporting of each sequential poppet.  Some versions have locking clutches that hold position when movement is not commanded.

The design I prefer for fine reverser adjustment is the wheel control in Franklin Precision screw reverse (they also made a lever type as I believe is found on NKP 765) and I used a modification of this with a split leadnut and some fixed and floating stops to allow quick excursions with a lever (e.g. for slip control) with return to known precise screw positioning afterward.  Quite unlike the screw reverse on 'certain British locomotive classes' this has no tendency to unwind under the load of the valve-gear components if accidentally released while being adjusted.

(I might add that with '40s technology it's also possible to servoadjust the screw to 'match needles' with a Valve Pilot arrangement, or to arrange feedback on the screw to facilitate finding the 'right' position without having to look at needles.)

[BaltACD]

Overmod

The design I prefer for fine reverser adjustment is the wheel control in Franklin Precision screw reverse (they also made a lever type as I believe is found on NKP 765) and I used a modification of this with a split leadnut and some fixed and floating stops to allow quick excursions with a lever (e.g. for slip control) with return to known precise screw positioning afterward.  Quite unlike the screw reverse on 'certain British locomotive classes' this has no tendency to unwind under the load of the valve-gear components if accidentally released while being adjusted.

(I might add that with '40s technology it's also possible to servoadjust the screw to 'match needles' with a Valve Pilot arrangement, or to arrange feedback on the screw to facilitate finding the 'right' position without having to look at needles.)

Is the screw reverser being used in this video?

https://m.youtube.com/watch?feature=youtu.be&v=NgRyIaJePnQ

[Jones1945]

Overmod

Not heavy at all.  Full lock-to-lock forward to reverse excursion can take place in a matter of one to two seconds if commanded, with controlled servo stopping of the inertia of the moving parts at any particular position.  There is no explicit 'force feedback' of the system inertias, much as in the controllers for the Huletts we discussed a while back.  Rack notches are not to hold the system against force, as in a Johnson-bar arrangement; they are for fine position holding in the relative absence of friction in the hand control.

The 1940s adoption of proportional air throttle control was in part designed to give this kind of stepless proportional control to a multiple-poppet throttle valve, which otherwise has mechanical loss of proportional control opening the first poppet and then in the ranges around progressive initial unporting of each sequential poppet.  Some versions have locking clutches that hold position when movement is not commanded.

The design I prefer for fine reverser adjustment is the wheel control in Franklin Precision screw reverse (they also made a lever type as I believe is found on NKP 765) and I used a modification of this with a split leadnut and some fixed and floating stops to allow quick excursions with a lever (e.g. for slip control) with return to known precise screw positioning afterward.  Quite unlike the screw reverse on 'certain British locomotive classes' this has no tendency to unwind under the load of the valve-gear components if accidentally released while being adjusted.

(I might add that with '40s technology it's also possible to servo adjust the screw to 'match needles' with a Valve Pilot arrangement, or to arrange feedback on the screw to facilitate finding the 'right' position without having to look at needles.)

Compelling! I always want to see a clear drawing or photo showing how a power reverse gear connected to the valve gears on different articulated steam engines like the UP Big Boy and C&O H-8 also rigid frame duplexes like the PRR S1, Q2; PRR Q1 and B&O N-1  ("face to face" valve gear), PRR T1 (duplex used poppet valve gear) and the T1 Trust 5550. Not really that simple to keep everything sync, I guess!

BaltACD

Is the screw reverser being used in this video?

https://m.youtube.com/watch?feature=youtu.be&v=NgRyIaJePnQ

 

A visual tour of the NYC (Dreyfuss) Hudson's cab (reverser at 02:41):