BaltACDHow much space are you allocating between axles - 40" wheels occupy 4 more inches than 36" wheels. If there were 2 inches of clearance between each of the 36" wheels - the 40" wheels won't fit the same axle spacing.
Have you actually LOOKED at one of these trucks?
Now, if you were to bring up the space available between the flange and some parts of the bolster structure between the wheels, you might have a more cogent argument; in fact, without looking at a dimensioned drawing I'd easily accept the argument that this is a controlling dimension for diameter increase. But the situation, even with those funky short-wheelbase Flexicoil clones, have the wheels far further apart than 'interference' distance (as in most steam-locomotive rigid wheelbases)
[quote]I suspect the traction motors are configured to occupy the space between the powered and unpowered axles on the truck.[/quotwithoute]
Remember that the motor is explicitly designed to fit between the gearcase and the back of the opposite wheel, and that there are strong reasons to keep the parts list as common as possible between different EMD units. It is not likely that a motor design accommodating 40" wheels on Fs would have its case, connections, nose-suspension arrangement etc. artificially widened when applied in passenger applications. I think I always assumed the 36" wheels had something to do with keeping drawbar height low to match passenger cars, as there's a long history favoring larger wheels for high speed as well as extended wear.
Things can get tricky when you start relating to things like gear ratios and the required pitch of the various gears that are necessary to mesh properly with each other.
Note that increasing the gearcase length even by 2" (to accommodate a hypothetical radius change of that size in going from 36" to 40") would almost certainly involve a different numerical radius on both the pinion and bull gears (to preserve the integral tooth forms on both. This is a major engineering and support change, one that I think someone like Dick Dilworth would not knowingly make when the alternative -- ensuring that the incremental 2" of motor and gearcase 'covered' by the larger wheels still fits between the wheel backs.
Meanwhile, aside from ancillary concerns like how to route the traction-motor cooling air (done ingeniously on Blomberg's C design, btw) there are two basic engineering concerns on where to hang nose-suspended motors. One is polar moment of inertia of the truck, which is increased, potentially massively, if the motors are outboard as opposed to being inside the wheelbase, and the other refers to weight transfer when the motor develops torque (it helps to have all the armatures turning the same way in a truck, which does not happen when motors 'face' each other).
Can I presume the FL-9 (B-A1A) had all 40" wheels? Was their A1A flexicoil truck unique to this model?
MidlandMikeCan I presume the FL-9 (B-A1A) had all 40" wheels?
Was their A1A flexicoil truck unique to this model?
There were North American locomotives with A-1-A Flexicoils, notable the GMD1, but to my knowledge those trucks were shorter wheelbase and had a smaller-diameter wheelset in the central position...
[/quote]
Overmod There were North American locomotives with A-1-A Flexicoils, notable the GMD1, but to my knowledge those trucks were shorter wheelbase and had a smaller-diameter wheelset in the central position...
I believe the GMD1 used a export truck design, very similar to what was found under the G8 etc.
Greetings from Alberta
-an Articulate Malcontent
Going back, for a moment, to transition: I do recall seeing manual transition once in my B&M days, on the "gas-car" or doodlebug, proably re-engined with a diesel, running Manchester, NH - Portsmouth, ME, which I rode, standing next to the engineer much of the way, Nashua - Portsmouth. Forward transition required shutting off power, pushing a button or a switch, and reapplying power one step at a time but quickly. Downward transition, the one or two times I saw it, was simply shutting off power, waiting and then re-applying power one step at a time but more slowly. Did any reader actually operate FTs or other diesels with manual transmission, and was the operation simiar?
Overmod BaltACD How much space are you allocating between axles - 40" wheels occupy 4 more inches than 36" wheels. If there were 2 inches of clearance between each of the 36" wheels - the 40" wheels won't fit the same axle spacing. Have you actually LOOKED at one of these trucks?
BaltACD How much space are you allocating between axles - 40" wheels occupy 4 more inches than 36" wheels. If there were 2 inches of clearance between each of the 36" wheels - the 40" wheels won't fit the same axle spacing.
I don't possess engineering drawings of the truck.
Never too old to have a happy childhood!
There probwbly was a thoiught to keep E-unit roof lines not much above the rooflines of lightweight passenger equipment.
What size(s) wheels did Alco use on DL-109s and PAs and PBs?
daveklepperThere probwbly was a thoiught to keep E-unit roof lines not much above the rooflines of lightweight passenger equipment. What size(s) wheels did Alco use on DL-109s and PAs and PBs?
The height of the original B&O EA's were less than 14 feet. E8's and E9's are 14' 7".
Overmod For standard service in this frame, yes. The Flexicoil was used because the original location for the third-rail shoes was on a long beam on the rear truck; the front truck on the 2 prototypes being like a standard swing-hanger B truck. That turned out to be a relatively crappy place for the third-rail shoe, so the front truck became a modified Flexicoil with a shoe beam installed. There were North American locomotives with A-1-A Flexicoils, notable the GMD1, but to my knowledge those trucks were shorter wheelbase and had a smaller-diameter wheelset in the central position...
For standard service in this frame, yes. The Flexicoil was used because the original location for the third-rail shoes was on a long beam on the rear truck; the front truck on the 2 prototypes being like a standard swing-hanger B truck. That turned out to be a relatively crappy place for the third-rail shoe, so the front truck became a modified Flexicoil with a shoe beam installed.
daveklepper There probwbly was a thoiught to keep E-unit roof lines not much above the rooflines of lightweight passenger equipment. What size(s) wheels did Alco use on DL-109s and PAs and PBs?
The one internet reference I could find says the PA's used 42" wheels.
Dave
Carsten's LOCO 1 - THE DIESEL shows the DL-109 running on 42" wheels, while the PA-1 had 40" idler wheels (suspect driving wheels were also 40").
BaltACD I don't possess engineering drawings of the truck.
What OM is referring to are the swing hangers on each side of the idler wheelset, with the swing hangers placed closer to the center wheelset than the outer wheelsets. The presence of the swing hangers and the center axle clasp brakes put a limit on the diameter of the center wheels.
daveklepperWhat size(s) wheels did Alco use on DL-109s...
To my knowledge everything in the somewhat-convoluted series from DL-103 to DL-110 had 40" wheels. The New Haven used GE 726 traction motors and had a nominal "120mph" on these wheels with 25:58 gearing (I list this pinion-first for tooth ratio as I recall PRR did, as it makes a little more sense to me; just reverse it for normal convention).
The ATSF used 21:62 in their DL-107s (nominal 100mph) with 726s, and this combination apparently didn't get over Raton successfully, leading apparently to much solder on the ties and exasperated comments about 'street car motors'.
This problem was addressed nicely in the DL-304/305 by going to larger-frame GE746-A2 motors (and in the MK rebuilds full 752s) which I recall being told was the reason for the 42" wheels. Oddly these were still rated as "100mph" with the same nominal gear ratio as the DL-107s (21:62) with the larger wheels.
Erik_Mag BaltACD I don't possess engineering drawings of the truck. The presence of the swing hangers and the center axle clasp brakes put a limit on the diameter of the center wheels.
The presence of the swing hangers and the center axle clasp brakes put a limit on the diameter of the center wheels.
Take a look at Blomberg's patent drawings for this truck to see the situation clearly (you can download the PDF and enlarge the drawing if desired):
https://patents.google.com/patent/US2189125A/en
Overmod Now, if you were to bring up the space available between the flange and some parts of the bolster structure between the wheels, you might have a more cogent argument; in fact, without looking at a dimensioned drawing I'd easily accept the argument that this is a controlling dimension for diameter increase. But the situation, even with those funky short-wheelbase Flexicoil clones, have the wheels far further apart than 'interference' distance (as in most steam-locomotive rigid wheelbases) Remember that the motor is explicitly designed to fit between the gearcase and the back of the opposite wheel, and that there are strong reasons to keep the parts list as common as possible between different EMD units. It is not likely that a motor design accommodating 40" wheels on Fs would have its case, connections, nose-suspension arrangement etc. artificially widened when applied in passenger applications. I think I always assumed the 36" wheels had something to do with keeping drawbar height low to match passenger cars, as there's a long history favoring larger wheels for high speed as well as extended wear. The number of the 'various gears' being exactly two, and their width in the gearcase essentially standardized across the range of possible ratios. What there is to be 'tricky' is the stuff I already described; the practical ratios being constrained on the one hand by stress in the pinion (Mr. Goding's note on hoop stress being comparable to what Sam Vauclain noted as the reason 26" ws the shortest practical stroke on the PRR T1s) and on the other by needing an integral number of carefully-formed and adequately-rooted teeth on each of the gears in a mating set. Note that increasing the gearcase length even by 2" (to accommodate a hypothetical radius change of that size in going from 36" to 40") would almost certainly involve a different numerical radius on both the pinion and bull gears (to preserve the integral tooth forms on both. This is a major engineering and support change, one that I think someone like Dick Dilworth would not knowingly make when the alternative -- ensuring that the incremental 2" of motor and gearcase 'covered' by the larger wheels still fits between the wheel backs. Meanwhile, aside from ancillary concerns like how to route the traction-motor cooling air (done ingeniously on Blomberg's C design, btw) there are two basic engineering concerns on where to hang nose-suspended motors. One is polar moment of inertia of the truck, which is increased, potentially massively, if the motors are outboard as opposed to being inside the wheelbase, and the other refers to weight transfer when the motor develops torque (it helps to have all the armatures turning the same way in a truck, which does not happen when motors 'face' each other).
The number of the 'various gears' being exactly two, and their width in the gearcase essentially standardized across the range of possible ratios. What there is to be 'tricky' is the stuff I already described; the practical ratios being constrained on the one hand by stress in the pinion (Mr. Goding's note on hoop stress being comparable to what Sam Vauclain noted as the reason 26" ws the shortest practical stroke on the PRR T1s) and on the other by needing an integral number of carefully-formed and adequately-rooted teeth on each of the gears in a mating set.
The E truck has a wheelbase of 169", the longest 3 axle truck wheelbase EMD has made - the HT-C and HTCR are both about 164". So space for larger wheels is not an issue of wheelbase, in fact, the HTCR-II on the 90MAC's fits 45" wheels in a 162" wheelbase.
Since the first D-series traction motor up to and including the SD60's D87B motors, the axle to armature distance has been 17.111" with 77 total teeth thru the -2's and 87 on the 50- and 60-series. The distance from axle center to the transom has been fixed at 37.25" so it means with a 40" wheel, there is 37.25-(.5*40)=17.25" from the wheel tread to the transom ignoring any contouring at the sideframe-transom junction. This is much more room than it takes to fit a brake lever/brake head/shoe in. The problem would be between the wheel and the end transom for which I have no dimensions. But the brake rigging on an E is arranged so the live lever (lever connected thru the crossover lever to the brake cylinder) is positioned at the end transom unlike all other EMD trucks where the live lever is on the inboard side of the wheel along side the traction motor. This makes it more difficult to modify for the wheel size but probably not impossible.
Regarding weight shift and motor orientation, with an A-1-A motor arrangement, it is generally superior to have the motors face each other as they do in the E truck as long as the truck has a soft pitch stiffness so the motor nose forces can balance each other. The closer the height of tractive effort from truck into the underframe is to the railhead, the lower the weight shift within the truck. When there are 3 motors, however, the weight shift is minimized when all motors face the same direction and the truck frame is inhibited from pitching via a stiff secondary suspension as it is in all modern freight trucks.
.
Overmod daveklepper What size(s) wheels did Alco use on DL-109s... The ATSF used 21:62 in their DL-107s (nominal 100mph) with 726s, and this combination apparently didn't get over Raton successfully, leading apparently to much solder on the ties and exasperated comments about 'street car motors'.
daveklepper What size(s) wheels did Alco use on DL-109s...
Santa Fe's DL107/108 set was built with GE 730 traction motors installed on 41" wheels with 56:25 gearing in May 1941. Those are the motors that failed on Raton. The units were remotored with GE 726 traction motors toward the end of WW2 and 40" wheels were installed.
SSW9389Santa Fe's DL107/108 set was built with GE 730 traction motors installed on 41" wheels with 56:25 gearing in May 1941. Those are the motors that failed on Raton. The units were remotored with GE 726 traction motors toward the end of WW2 and 40" wheels were installed.
This gets more and more interesting -- point me at a good tech reference. I had the impression that the 730s were recommended for passenger service and 726s for freight, but the dieselshop reference only mentioned 726s for the DL-107 stats (on what could be presumed, on ATSF, to be decidedly fast passenger service), so I was suckered in. (Presumably this was the as-rebuilt configuration -- are they also correct in their given gear ratio for the 40" wheels?)
Larry Brasher (Jr.) is not very positive in his recounting of that trip west. He describes the idle of those four motors as being so rough that the sides of the units were visibly flexing, and coffee was being sloshed in the buffet through the tightlock couplers. I wonder what other issues were observed in service.
bogie_engineer daveklepper Apparently, I was in error on the very last DC motors. What about AC motors today? Are there varieties or just one for EMD-Progress Rail? Should be possible to do the job with just one type. EMD has used 3 different motor diameters and several core lengths. The first is the Siemens 1TB2630 which was used in the SD70MAC, designed to take up the space between a gearcase and the opposite wheel in a standard gauge application. Variations of this same diameter were the 1TB2626 as used in the F69PH-AC and the 1TB2624 used in the LIRR DE/DM30AC's. This diameter was also used in the locos for India but I can't recall the length. The first two digits denote the diameter and the second two the core length but it's not any particular units like inches. These motors are designed for 42" minimum new wheels with 1.5" radial wear material (fully worn at 39"). The second size is a bigger diameter as used in the SD80 and 90MAC's, that was also a Siemens designed motor designated 1TB2830 roughly 3" larger in diameter IIRC. This is the only application of this motor size, which requires at least 44" dia new wheels. The bigger motor motor was needed to meet the design requirement of 200Klbs. tractive effort. With the split from Siemens to using Mitsubishi inverters starting with the SD70ACe, EMD designed in house a new series of AC motors with diameter between the two Siemens motors to have capacity for 200Klbs. TE with 6 motors. This family of motors is designated A29XX and requires 42" new wheels. It's now used on all EMD/Progress Rail locos in widths to fit from meter to standard gauge, wider than standard uses standard gauge or smaller motors depending on axle load. All traction motors are now made in a facility in Mexico. Dave
daveklepper Apparently, I was in error on the very last DC motors. What about AC motors today? Are there varieties or just one for EMD-Progress Rail? Should be possible to do the job with just one type.
Apparently, I was in error on the very last DC motors. What about AC motors today? Are there varieties or just one for EMD-Progress Rail? Should be possible to do the job with just one type.
EMD has used 3 different motor diameters and several core lengths. The first is the Siemens 1TB2630 which was used in the SD70MAC, designed to take up the space between a gearcase and the opposite wheel in a standard gauge application. Variations of this same diameter were the 1TB2626 as used in the F69PH-AC and the 1TB2624 used in the LIRR DE/DM30AC's. This diameter was also used in the locos for India but I can't recall the length. The first two digits denote the diameter and the second two the core length but it's not any particular units like inches. These motors are designed for 42" minimum new wheels with 1.5" radial wear material (fully worn at 39").
The second size is a bigger diameter as used in the SD80 and 90MAC's, that was also a Siemens designed motor designated 1TB2830 roughly 3" larger in diameter IIRC. This is the only application of this motor size, which requires at least 44" dia new wheels. The bigger motor motor was needed to meet the design requirement of 200Klbs. tractive effort.
With the split from Siemens to using Mitsubishi inverters starting with the SD70ACe, EMD designed in house a new series of AC motors with diameter between the two Siemens motors to have capacity for 200Klbs. TE with 6 motors. This family of motors is designated A29XX and requires 42" new wheels. It's now used on all EMD/Progress Rail locos in widths to fit from meter to standard gauge, wider than standard uses standard gauge or smaller motors depending on axle load. All traction motors are now made in a facility in Mexico.
The following link gives the details of the AC traction Motors used in India:
http://trainweb.org/railworld/WDG5/EMD%20TMs.pdf
This includes the GT46 MAC (WDG-4) and the 20 cylinder WDG-5.
The WDG-4 has German, USA, Chinese and Indian traction motors....
Also, the Australian built GT42CU-AC (42" gauge, 62 units) had Siemens 1TB2622 traction motors while the later GT42CU ACe (42" gauge, 132 units) had EMD A2619-8 traction motors. These are the most numerous 42" gauge units in Australia, the others being three GE Powehaul units and five Chinese SDA-2 units with 20 cylinder MTU engines.
The most numerous AC units in Australia are GE C44 ACi units with GE GEB30 motors, although there are a number of heavier C44 ACHi units with domestic GEB13 motors. I'd like to know more details about the GEB30....
The C44ACi compete in Ausralia with the EMD GT46C-ACe which in the Australian version uses 1TB2630 motors. On trials on steep main line grades (2.5%) the EMD units outperformed the GE units dramatically and GE had to alter their control programming even to reach the top of the grade in wet conditions.
Peter
SSW9389 This was written about the F3 by a fellow Kentuckian back in the late 1940s. THE AGE OF THE F-3 “Motive Power historians may well look back at our times, terming them “The Age of the F-3.” The pacemaking performance of Electro-Motive’s fabulous 1500-horsepower road diesel unit last year only accented the unparalleled sales success that the F-3 has been enjoying ever since its birth in October of 1946. Since then EMD has mass-produced it to a staggering 2.3 million horsepower represented by over 1500 cab and booster units, now hauling freight and holding down passenger schedules in three countries: the United States, Canada and Mexico. In all of locomotive history there is not even a close runner-up to that batting average; no other basic unit of motive power has gone so far and done so much in so short a time. Last year the F-3 introduced road after road to dieselized freight service, including potato carrying Bangor & Aroostook and orange hauling Florida East Coast; this year it will carry the banner to such new customer as the Clinchfield Atlanta & West Point, Texas & Pacific and Georgia.” Ed in Kentucky
This was written about the F3 by a fellow Kentuckian back in the late 1940s.
THE AGE OF THE F-3
“Motive Power historians may well look back at our times, terming them “The Age of the F-3.” The pacemaking performance of Electro-Motive’s fabulous 1500-horsepower road diesel unit last year only accented the unparalleled sales success that the F-3 has been enjoying ever since its birth in October of 1946. Since then EMD has mass-produced it to a staggering 2.3 million horsepower represented by over 1500 cab and booster units, now hauling freight and holding down passenger schedules in three countries: the United States, Canada and Mexico. In all of locomotive history there is not even a close runner-up to that batting average; no other basic unit of motive power has gone so far and done so much in so short a time. Last year the F-3 introduced road after road to dieselized freight service, including potato carrying Bangor & Aroostook and orange hauling Florida East Coast; this year it will carry the banner to such new customer as the Clinchfield Atlanta & West Point, Texas & Pacific and Georgia.”
Ed in Kentucky
The article in April 1949 TRAINS is considered to be the first of the annual Motive Power Surveys.
FYI: The April 1949 DPM Article The shift from Steam was reprinted with new color photos in the 2014 Classic Trains special edition Trains of the 1940s. the 1950 MPS The Locomotive in 1949 was included in the 2020 CT special More Trains of the 1940s.
It's not too surprising that Sales and Engineering were still at work. Neither was part of the bargaining unit. Sales is probably commission work and the Engineering staff was probably on the monthly payroll.
SSW9389After the UAW strike hit EMD on Wednesday November 21, 1945 there were still some employees working. Management and administration were working. The Sales Department was still pushing the product. There's mention of 1500 horsepower diesel orders in Trains January 1946. The Engineering department was still working. Testing of the 291 demonstrator was ongoing during the strike. The last EMD shipping date for 1945 is shown as Friday November 30th. So some folks did that work. Was the parts department open? What's especially interesting on this is that both Sales and Engineering were still working during the strike. Ed in Kentucky
When a particular Union strikes, the members of that Union are on strike and most likely will set up Picket Lines. Members of other Unions most likely will honor the picket lines of those on strike. Non-Union member most likely will not honor the picket lines and will attempt to conduct normal business operations.
It was 75 years ago this month that EMD published at least two operating manuals for the F2 diesel. The manuals were for the Rock Island and Southern F2s that would be delivered in July 1946. The entire Rock Island F2 operating manual is hosted on the fallen flags website by George Elwood. See http://www.rr-fallenflags.org/manual/f2-om.pdf
Let me jump in with a couple points - I haven't read every word of the previous posts so sorry if I duplicate something someone already wrote....
1. I believe GM stopped making FTs largely because they had 5 years of input from railroads of changes / improvements that they wanted.
2. FTs certainly could M.U. with other engines. The problem was that, as designed, FTs were meant to be A-B units, with a drawbar between the two units. GM did jerry-rig a coupler set up for ATSF, and developed the FTSB (FT Short Booster) so railroads could run an A-B-A set of FTs (although there was no room for a steam boiler, so this could only be used for freight trains.) One of the changes made with the F2 and all later Fs was having the trucks spaced differently so a railroad could have couplers on both ends of both units if they wished.
3. Since FTs were only A-B sets as designed, you either had 2700 HP (one A-B set) or 5400 HP (two A-B sets back-to-back). Mainline freights generally needed around 4000 HP, so you had too much or too little. Many railroads did buy F2 and F3 A units to add to FT sets to have an A-B-A set with 4050 or 4200 HP.
4. As I think was noted, the F2 was supposed to increase horsepower from the FTs 1350 to 1500, but couldn't due to one part that GM couldn't get at the time. Once that part was available, they started making 1500 HP engines and re-designated it as the F3. Otherwise the F2 and F3 were the same engine.
Does anyone have any insight as to the where and when EMD tested the D8B, Dog Eight Baker, generator used on the F2? The D8B was the generator from the FT mated with the D14 companion alternator. Ed in Kentucky
SSW9389Does anyone have any insight as to the where and when EMD tested the D8B, Dog Eight Baker, generator used on the F2? The D8B was the generator from the FT mated with the D14 companion alternator.
I would ask this question over on RyPN as you're much likelier to get a detailed answer there.
Thanks Overmod for the good advice. I'll write Preston Cook and ask. And with that thought there is a bit of F2 information in an article by Cook's mentor at EMD: W. A. Gardner. See "Delivering EMD's Locomotives" in the November 1980 issue of Trains, pp 50-60. Gardner was on hand to deliver B&M's F2 units.
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