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Just an additional comment about two of many subtle things that were captured . . .

In O Gauge Railroading's DVD Great Layout Adventures, Volume 8, Rich Melvin interviews Hot Water about his railroad, and also about his experience in firing large steam engines.  At one point Hot Water is describing the difference between firing a coal-fired engine vs an oil burner, and the requirement that the Fireman be responsive to adjusting the burner in tune with throttle changes by the Engineer.  

Hot describes how Doyle McCormack uses the air horn valve to create a couple of quick "psst-psst" sounds  in the cab, to get the Fireman's attention, as Doyle is preparing to increase or reduce throttle.  

These audible signals are heard at least twice during the Daylight Express video, as is the exhaust from the No.8 automatic brake valve on the 4449 as Doyle moves the handle to Service and back to Lap while making small reductions while approaching a station stop.

Last edited by Number 90
Hot Water posted:
Norton posted:

I agree, this is an excellent video. Would this have been the same route the Shasta Daylight ran?

Pete

Yes. Portland, OR to Sacramento and then Oakland/San Francisco.

Really enjoyed the video of this timeless masterpiece.

Any idea why the Daylight required two helpers on the decent from MT Shasta?  If it was mentioned in the video I must have missed it

Norton posted:
daylight posted

Really enjoyed the video of this timeless masterpiece.

Any idea why the Daylight required two helpers on the decent from MT Shasta?  If it was mentioned in the video I must have missed it

I think it was mentioned they were added to help with braking for the Cantera loop.

Pete

Correct. Whenever we traveled over mountain grades, we generally just added the helpers on the point, so they could be easily removed at the end of a "helper district".

Hot Water posted:
Norton posted:
daylight posted

Really enjoyed the video of this timeless masterpiece.

Any idea why the Daylight required two helpers on the decent from MT Shasta?  If it was mentioned in the video I must have missed it

I think it was mentioned they were added to help with braking for the Cantera loop.

Pete

Correct. Whenever we traveled over mountain grades, we generally just added the helpers on the point, so they could be easily removed at the end of a "helper district".

Thank you guys, that is what I thought.  AS far as the braking issue, was the Daylight and the associated passenger cars not able to brake enough to slow the trains momentum down the grade?

daylight posted:
Hot Water posted:
Norton posted:
daylight posted

Really enjoyed the video of this timeless masterpiece.

Any idea why the Daylight required two helpers on the decent from MT Shasta?  If it was mentioned in the video I must have missed it

I think it was mentioned they were added to help with braking for the Cantera loop.

Pete

Correct. Whenever we traveled over mountain grades, we generally just added the helpers on the point, so they could be easily removed at the end of a "helper district".

Thank you guys, that is what I thought.  AS far as the braking issue, was the Daylight and the associated passenger cars not able to brake enough to slow the trains momentum down the grade?

Yes, the passenger train was very capable of barking itself down steep mountain grades, just as it would have been done back in the steam days, i.e. prior to diesels with dynamic brake. But,,,,,,,,,what's the point? Why put excessive wear on the brake shoes and wheels, descending a 2.2% mountain grade with VERY tight curves, when it takes very little time to add and remove diesel helpers?

daylight posted:
 was the Daylight and the associated passenger cars not able to brake enough to slow the trains momentum down the grade?

Of course the steam engine and cars had adequate braking power to descend the grade without a diesel helper!

There were three reasons to double-head the train with the diesel:

  1. Reduce brake shoe wear, and thereby expense and manpower.
  2. Smooth, single-brake application, train handling.
  3. Descend the grade at higher speed due to having dynamic brake in use.

The diesels provided dynamic braking, which greatly reduced the amount of air braking needed on the descending grade, thereby saving brake shoe wear.  The Daylight train was maintained by volunteers, donations, and private owners, and changing all the brake shoes after the trip would have been quite expensive and time consuming.

Also, the diesel had a pressure-maintaining 26-C brake valve, which prevents the brake pipe from leaking down and further applying the brakes during a long brake application, such as when descending a continuous grade for miles.  The 4449 has 8-ET brake equipment -- the finest available in 1941 -- but it cannot prevent further brake pipe reduction from leakage while the train brakes are applied.  When the brake pipe pressure leaks down during a brake application, it increases the pressure of the brake shoes against the wheels, giving more retarding force, and eventually will get to the point where the train stalls on the descending grade.

So, the diesel, controlling the air brakes, as is required of the front engine, could use dynamic braking and thereby use less severe air braking; and it could also allow better train handling by enabling the Engineer to make a light brake application and hold it, varying the dynamic brake effort to keep the speed constant at whatever speed he intended to run.  The 4449 without the diesel helper would have had to use cycle braking -- set the brakes, slow down to 5-7 MPH below the target speed, release the brakes, reapply the brakes at the target speed and reduce to below target speed, etc., and even pull the train with brakes applied in a few flatter places.   Also, there may have been a lower maximum allowable speed on this descending grade for trains without dynamic brake in use.  Usually there is. 

No matter how good the Engineer is, cycle braking produces some coupler slack action within a passenger train, and, while not severe enough to send grandmothers to the other end of the car they are riding in or to rearrange the table settings in the dining car, it would have been noticeable, and therefore could be avoided by the diesel's dynamic braking and its pressure-maintaining brake valve.

This may be a little technical for those not familiar with train and locomotive air brakes and train handling, so I have underlined some key words and phrases to help when reading these long and technical sentences.

Last edited by Number 90
Brandy posted:

Great thank you from me as well....One of the best I've ever seen.............................Brandy!....

Hot Water, are you still working on the  4449 engine crew??..... 

Yes, although I haven't been out to Portland since 2012. The FRA mandated 15 year work was completed last year, and I was not able to attend the 40th anniversary "reunion" of the American Freedom Train folks this past weekend. If another excursion can be organized for 2017, then I should be able to make that.

 

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