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EMC TA TRUCKS (R. I. Rocket locomotives)

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RME
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Posted by RME on Thursday, March 24, 2016 7:38 PM

NorthWest
I take it the quote is from Railroad.net?

Yes, from a four-page post on early Alco-GE traction motors, which only peripherally mentions the 716s.

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Posted by NorthWest on Thursday, March 24, 2016 5:09 PM

Welcome RME, and thanks for the drawings! (Haven't we seen those initials before?)

I take it the quote is from Railroad.net?

RME
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Posted by RME on Thursday, March 24, 2016 6:41 AM

SSW9389
What type of GE traction motors were originally used on these unique Rock Island units?

Apparently 716s. 

Here are some drawings, thanks to the ineffable Sam Berliner (who tracked them down as provided on one of the IC 9200 boxcabs!)

In connection with this, Allen Hazen noted (a decade ago):

I'm not sure of my memory here, but I think Kalmbach's "Our EMD Scrapbook" (compilation of old "Trains" articles, mostly-- I think-- by David P. Morgan) somewhere says that the basic EMD traction motor was pretty much a copy of the GE motor they had been using before opening the La Grange plant and making their own electrical gear, and that EMD armatures "until recent times"-- this was probably published in the late 1960s-- were interchangeable with armatures from GE motors of the 1930s.

 

I'm sure Will Davis (or one of the other 'usual suspects' with good knowledge and high regard for source-material integrity can provide more information on this, perhaps with comparison to these drawings.

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Posted by rcdrye on Thursday, March 24, 2016 6:28 AM

SSW9389
The EMD Product Reference shows that the TA units had GE electrical gear. What type of GE traction motors were originally used on these unique Rock Island units? Ed in Kentucky
 

Most likely GE model 726.  GE shifted to the 752 with early PA.  There is still a version of the 752 made today for use in drilling rigs.

EMC introduced its own D7 traction motors under the early NW and E units.  The first units delivered with EMC motors were Soo Line (WC) 2100-2102 model NW1A.

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Posted by daveklepper on Thursday, March 24, 2016 4:08 AM

[quote user="Domer66"]

Thinking EMC/EMD and railroad trucks makes me instantly wonder if Martin Blomberg did not have a hand in this truck design. He is credited with the AAR Type A switcher truck design as well as the Blomberg B/M, partial assistance on EMD A1A and while at Pullman Company assisted with the UP M10000 design among others.

 

[/quote is above]

But the basic concept of the Commonwealth drop equalizer design is a lot older than diesel locomotives.  Is it not the normal design for eight-wheel passenger equipment in North America and first used around 1870 under wood open-platform passenger cars?

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Posted by SSW9389 on Thursday, March 24, 2016 1:21 AM
The EMD Product Reference shows that the TA units had GE electrical gear. What type of GE traction motors were originally used on these unique Rock Island units? Ed in Kentucky
COTTON BELT: Runs like a Blue Streak!
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Posted by Domer66 on Wednesday, March 23, 2016 10:21 PM

Thinking EMC/EMD and railroad trucks makes me instantly wonder if Martin Blomberg did not have a hand in this truck design. He is credited with the AAR Type A switcher truck design as well as the Blomberg B/M, partial assistance on EMD A1A and while at Pullman Company assisted with the UP M10000 design among others.

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Posted by Wizlish on Tuesday, March 22, 2016 2:11 PM

daveklepper
And possibly those trucks would eventually give problems with the starting tractive effort required with an FT unit on a freight train, but be OK for passenger service.

I don't think there was any more of a "problem" with starting concerns (particularly weight transfer) on the Commonwealth/GSC design that became the "AAR type B" -- heaven knows it saw service under any number of EMD locomotives that would otherwise have had Blombergs -- but I think that Blomberg's swing-hanger B truck design was superior in other respects, particularly lateral compliance.

Certainly one of the stated reasons for GE developing the FB-2 to replace this design was lower or 'zero weight transfer'.  But that was decades later.

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Posted by daveklepper on Tuesday, March 22, 2016 1:47 PM

Thanks.   That makes sense.  And possibly those trucks would eventually give problems with the starting tractive effort required with an FT unit on a freight train, but be OK for passenger service.

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Posted by Wizlish on Tuesday, March 22, 2016 1:43 PM

daveklepper
What was the design of the TA's truck for the Rock Island Rockets?

Commonwealth (at this point in time) drop-equalizer trucks, which seem similar if not identical to the ones in use on contemporary UP Streamliner power.  Here is a picture on Richard Leonard's site that shows the truck detail particularly well.

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Posted by 16-567D3A on Tuesday, March 22, 2016 1:36 PM

.

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EMC TA TRUCKS (R. I. Rocket locomotives)
Posted by daveklepper on Tuesday, March 22, 2016 10:42 AM

The two-axle, two-motor Blomberg truck was introduced with the demonstration FT.   What was the design of the TA's truck for the Rock Island Rockets?

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