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Did GN O-8 2-8-2s really have 71" drivers?

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Posted by Overmod on Monday, August 17, 2020 6:22 PM

PNWRMNM
The R class was intended to work over the Rocky Mountains between Whitefish and Cut Bank or Havre. Ruling grade was 1% westward, and 1.8% eastward. They were built to get tonnage trains over the mountains, not to be speed demons. Why ever would GN go to a less capable engine?

For just the same reason D&H would go to Challengers and away from drag power later in the Thirties.  This particularly given the advantages you note GN's line had over its 'competition'.

Compare what New Haven was initiating in service as early as 1931... in an environment where rates were regulated and hence both choice of carrier and emergence of new competitive service 'opportunities' like expedited bridge traffic would depend on cost-effective performance.

There are likely performance gains for fast freight at least comparable to what the original AMC Berks offered over comparably-cylindered Mikados...

For passenger service the GN had their 1929 built S-1 4-8-4 rated at 68,466# of TE on 73 inch drivers and their 1930 built S-2 rated at 58,300# of TE on 80 inch drivers. With the arrival of the S-2, the six S-1 engines were bumped to freight service. Alco's proposal looks like a lot of complication for not much gain.

Both these engines were from an age of insufficient balancing and the wrong bore vs. stroke for lightweight conversion.  Not that the S-2 wasn't an excellent design, just that the way to actually get meaningful performance out of one wouldn't be 'known' for a few more years ... and to my knowledge GN never did rebuild these to get the prospective speed out of them.

The Alco design was complete overkill for the likely benefit ... unless GN actually had, or could develop, or was considering, accelerating at least some part of a passenger or M&E service to Milwaukee-esque levels -- which is something you would know perhaps better than anyone.  It may be just me, but I can't imagine Alco doing a design for an 84"-drive red duplex with 127' grate on spec ... or arriving at those dimensions by looking over at Baldwin and cribbing what was essentially a Viper-style cartoon of a flatland road locomotive to flog to Mr. Hill's most excellent railroad...

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Posted by PNWRMNM on Tuesday, August 18, 2020 7:35 AM

Yes, Challengers east of Havre could have run like the wind, but lumber and grain, the predominant traffic, was not particularly time sensative.

More importantly, due to terrible earnings during the Great Depression, and impending bond maturities, the GN did not have the money for new power. Net income dropped from $35 million in 1929 to 5.3 million in 1931 to a deficit of $13.4 million in 1932.

As of 1930 the GN had to pay down or refund the following bonds:

$42 million       Manitoba Consolidated Mtge      due July 1, 1933

$106 million     GN General Mtg                        due July 1, 1936

$20 million       Montana Extension and

                      Montana Central                       due July 1, 1937

3.6 million       Willmar & Sioux Falls                due June 1,1938

Given these demands, and power stored due to traffic declines, new power was an unnecessary frill.

By the time these bonds were dealt with and traffic recovered enough that new power was desireable, the FT was available. GN bought a few in 1939-40, and a larger batch in 1944. IIRC GN was the #2 user of FTs, second only to Santa Fe.

I think that the GN sitting out the 1930s in terms of steam purchases was a net benefit, not that anyone in 1930 saw the FT comming.

Mac

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Posted by BaltACD on Wednesday, August 19, 2020 10:02 PM

PNWRMNM
Yes, Challengers east of Havre could have run like the wind, but lumber and grain, the predominant traffic, was not particularly time sensative.

More importantly, due to terrible earnings during the Great Depression, and impending bond maturities, the GN did not have the money for new power. Net income dropped from $35 million in 1929 to 5.3 million in 1931 to a deficit of $13.4 million in 1932.

As of 1930 the GN had to pay down or refund the following bonds:

$42 million       Manitoba Consolidated Mtge      due July 1, 1933

$106 million     GN General Mtg                        due July 1, 1936

$20 million       Montana Extension and

                      Montana Central                       due July 1, 1937

3.6 million       Willmar & Sioux Falls                due June 1,1938

Given these demands, and power stored due to traffic declines, new power was an unnecessary frill.

By the time these bonds were dealt with and traffic recovered enough that new power was desireable, the FT was available. GN bought a few in 1939-40, and a larger batch in 1944. IIRC GN was the #2 user of FTs, second only to Santa Fe.

I think that the GN sitting out the 1930s in terms of steam purchases was a net benefit, not that anyone in 1930 saw the FT comming.

Mac

 

Those that got high numbers of FT's during WW II got them because the War Production Board wanted those carriers to get them - many other carriers desired FT's some got less than they wanted and had to supplement their fleets with new steam engines - some got none and also had to resort to new steam engines to fulfill their power needs.

Never too old to have a happy childhood!

              

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Posted by CSSHEGEWISCH on Monday, August 24, 2020 10:14 AM

It worked in the other direction, too.  M&StL wanted 2-6-6-4's (similar to SAL) and got FT's instead.

The daily commute is part of everyday life but I get two rides a day out of it. Paul
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Posted by 7j43k on Tuesday, August 25, 2020 5:00 PM

From the Great Northern diagram for O-8's 3375-3399:

Driver diameter 69"

Weight on each driver axle 81250

Weight on lead truck axle 30340

Weight on trailing truck axle 70200

TE at 83.5% working pressure 75900 (working pressure 250 lbs)

Grate area 98.5 sqft

 

From Alfred W. Bruce's "The Steam Locomotive in America", NKP 2-8-4 #776:

Driver diameter 69"

Weight on each driver axle 66500

Weight on lead truck axle ?

Weight on trailing truck axles ?

TE 64100 (BP 245 lbs)

Grate area 90.3 sqft

 

Ed

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