Date   

moving cars on summary waybills

Anthony Thompson <thompson@...>
 

In following up on an earlier blog post about handling cuts of cars, my friend Larry Kline put me in touch with Gene P. Schaeffer, who was kind enough to send me copies of additional "mine ticket" bills used to move coal traffic, and to explain how they were used. I have now written a second post to present this additional information. My own interest is in the general subject of this kind of car handling, not specifically in coal handling, but I feel these documents are quite intriguing in that general sense as well as in the specifics of coal traffic. If interested, here is a link:

http://modelingthesp.blogspot.com/2012/04/waybills-23-cuts-of-cars-update.html

Tony Thompson Editor, Signature Press, Berkeley, CA
2906 Forest Ave., Berkeley, CA 94705 www.signaturepress.com
(510) 540-6538; fax, (510) 540-1937; e-mail, thompson@...
Publishers of books on railroad history


Re: Weathering Lighter Colored Cars

Aley, Jeff A
 

Michael,

First of all, your photos are now approved, and members may view them at http://groups.yahoo.com/group/STMFC/photos/album/1111246025/pic/list

Second of all, very nice weathering! You have a achieved the very delicate balance between "heavily weathered" and "overdone". The cars all have a natural look to them (compared to some of mine that scream "look! I've been weathered!").

Regards,

-Jeff


From: STMFC@... [mailto:STMFC@...] On Behalf Of atsfnut
Sent: Thursday, April 26, 2012 8:39 PM
To: STMFC@...
Subject: [STMFC] Re: Weathering Lighter Colored Cars



Dear Charles and Group,

I've been reading with interest the postings about weathering lighter colored cars and, with respect to washes, wanted to share some of my experience.

To begin with, I wash with solvent-based paints, usually enamels (Model Master, Testors, etc.) or tube oils, because I find that acrylics dry too quickly for me to control their application. These are always applied over a fully cured acrylic matte finish which protects the factory paint and lettering.

Several types of treatments have been described in the postings. One is the attempt to provide an overall "fade" or bleached look to the factory paint. You may be familiar with modeler and author Pelle Søeborg, who accomplishes this by airbrushing a thinned solution of Model Master "sand" to his models.

I customarily use washes to give depth to a model-"shadows," if you will. This typically consists of a darker, sympathetic shade of the base color applied with a brush, then wiped away with cotton swabs, sponges, etc. Most is removed, but the residue of this wash settles into cracks, depressions and along rivet lines, providing visual interest. The philosophy for lighter cars is exactly the same as with darker cars: use a darker, harmonious version of the base color applied with a much greater proportion of thinner to paint-a "tinted thinner," if you will. By "harmonious," I mean that warm colors (gold, bronze, copper, brown, tan, yellow, red, orange, maroon, off-whites) are applied to warm colors, and cool colors (black, pure white, silver, blues, greens, grays and some purples) are applied to cool.

For a boxcar red model, I will typically wash with a darker version of that red: raw umber or burnt sienna, for example. For an orange or a yellow car, I might use something lighter: light yellow ochre, or a raw sienna. Again, something darker, but in harmony with the base color.

There are no "rules," as the amount and intensity of the wash is up to you. The guiding principle must always be harmony: a darker version of the base color makes an effective color-contrast wash.

Mind you, I use this type of wash only as a first step, and usually apply other weathering effects: atmospheric (rain, sun, etc.); terrestrial (dirt, soot, wheel-throw); and man-made (dings, scrapes, spills, etc.) only after applying the wash.

There are many ways to do this and many tools available for your use, but this is the method I use, and I trust it provides you with another set of options.

Cheers!

Michael Gross
La Cañada, CA

--- In STMFC@...<mailto:STMFC%40yahoogroups.com>, "Charles Hostetler" <cesicjh@...<mailto:cesicjh@...>> wrote:

Good Evening,

My first three weathering tries were on basic black hoppers. I just finished weathering a PCCX hopper in the yellow scheme, hoping to get some experience with a lighter colored car before I tackle my Shake N Take Hormel reefers:

http://cnwmodeling.blogspot.com/2012/04/pccx-6401-6425-usra-twin-hopper.html


I think I found out that a lighter colored acrylic wash is necessary for application to a lighter colored car. The darker wash ended up looking "muddy" (and I don't mean that in a good way) before I scrubbed it off and lightened it up a lot. Would some of you with more experience be willing to comment on this observation?

Regards,

Charles Hostetler
Goshen, IN


[Non-text portions of this message have been removed]


Re: "Freight Traffic" Book

Aley, Jeff A
 

Jerry,

IIRC, these are merely issues of Railway Age. Every so often (quarterly? Annually?) Railway Age would designate a magazine issue as the "Freight Traffic" issue.

Regards,

-Jeff


From: STMFC@... [mailto:STMFC@...] On Behalf Of asychis@...
Sent: Friday, April 27, 2012 7:31 AM
To: STMFC@...
Subject: [STMFC] "Freight Traffic" Book



Is anyone familiar with a publication, actually I think a yearly book
entitled "Freight Traffic?" I have seen it occasionally on e-Bay and wonder
what useful information it might contain.

Thanks,

Jerry Michels


Terminolgy (Was: Re: Roller Bearing advantage)

mopacfirst
 

I too am a mechanical engineer, and I thought I was the one who pushed Richard's button.

I spend a considerable amount of time trying to get young engineers to use the specific terminology or the terminology that's actually used in standards, and the best I can get is that, after they've already picked up all the informal terms and the terms that became obsolete thirty years ago that everyone still uses, that some of them can remember to use the proper terminology when they come to see me because they know I'll correct them.

So much for leaving the world a better place.....

Ron Merrick


"Freight Traffic" Book

asychis@...
 

Is anyone familiar with a publication, actually I think a yearly book
entitled "Freight Traffic?" I have seen it occasionally on e-Bay and wonder
what useful information it might contain.

Thanks,

Jerry Michels


Re: decals derailed

James Babcock
 

Thank you for the notice. I hope that the situation resolves itself quickly.
Jim
 
________________________________

From: Gerald Glow <jerryglow@...>
To: STMFC@...
Sent: Friday, April 27, 2012 8:54 AM
Subject: [STMFC] decals derailed




 

I regret to inform you that effective immediately, I'm suspending all
decal sales. The mechanical issues with the printer at the print house
that does my printing continues to worsen making it impossible to
guarantee delivery in a timely manner. I will post here when the
situation is solved and sales resume.

I will do my best to fill any current open orders with decals on hand,
and refunds partial or full issued.

My web site will also contain notification when the situation improves
so check it occasionally.

--
Jerry Glow
The Villages FL
http://home.comcast.net/~jerryglow/decals/

[Non-text portions of this message have been removed]




[Non-text portions of this message have been removed]


Re: Roller Bearing advantage

devansprr
 

John,

First, full disclosure. While I am a mechanical engineer, I am not a bearing design engineer. Engineers that go into that field are making a life-time professional commitment. It is a very sophisticated field.

So I am not an expert, but the theory behind roller bearings, and the reason they are referred to as "anti-friction" bearings, is that in the ideal design there are NO sliding surfaces anywhere in the bearing. ALL loaded surfaces involve rolling "point" or "line" contact with NO slippage (just as the "ideal" line contact for a steel wheel on steel rail should not have any slippage). If there is no slippage, then there is no "friction" (but there are other losses - fortunately they are much lower than sliding friction).

I believe that the "ideal" is VERY difficult to attain in nearly all bearing applications - but I think you can come pretty close in some applications, and freight car wheel bearings may actually be one of them.

What surprised me last night going through the 1940 CBC was how "primitive" (by today's standards), the roller bearings were for the STMFC era (20 years prior to the end of the STMFC era). The SKF bearings were somewhere between spherical (ball bearing) and taper. As a result, while portions of the contact area were truly rolling, near the edges of the contact area there was slipping under load. And if there was slipping, it must be lubricated. So it looks like they immersed the roller bearings in oil.

But with all of that oil being squeezed and pushed around, the roller bearing is beginning to look like the automotive equivalent of a gear driven engine lube oil pump - but without a discharge. So a lot of work is done to move that oil around - but only as speed increases (which explains why the rolling resistance of a 1942 era roller bearing was comparable to a journal bearing at higher speeds.)

In this era I am sure there was also considerable conservatism from a business standpoint. I can imagine a tapered roller bearing engineer telling management that these bearings really DO NOT require oil immersion - and management unwilling to take what they perceived as significant financial risk and/or having to convince every railroad mechanical engineering head that lubrication was not required. I am 99% sure the engineer would lose that argument. So in the 1940 CBC the roller bearing ads focused on "Journal boxes" that would maintain lubrication of the roller bearing while keeping out the dirt.

In a quick scan of the 1940 CBC, it did seem that Timken was a lot closer to the "ideal" tapered roller bearing than the others, which is likely why they were using "Timken Bearings" as a trademark of sorts.

Fast forward 70 years to today's modern tapered roller bearing. In these bearings, machined to mirror finishes, the "line" contact areas that carry/transmit the "principle" loads (car weight and thrust loads in curves) are truly rolling along the entire contact area. So no sliding friction from the "primary" loads. But there are locations in the bearing where secondary loads involve some sliding (e.g the forces that may keep the rollers in the proper location), so some lubricant is required. The bearing designer's challenge is to minimize these forces at sliding points of contact. In the case of modern freight car bearings, the lubrication is a "lifetime" surface lubricant (I think defined as 6 years - but I am not sure), and the bearings do NOT have lubrication fittings (introducing grease would likely ruin the bearing).

In fact, grease can be viewed as a "dirt" magnet in these bearings. The real design challenge today is making seals, which DO include sliding surfaces, that last 6 years and keep dirt out of the bearing's internals.

As for modern road trucks and their roller bearing use - I really do not know why they are using oil immersion. Bearing design is very complicated, and often involves taking many other factors into consideration - including the nature of the equipment it is being installed into. But an oil filled roller bearing will have higher losses than a dry roller bearing. Whether that dry roller bearing survives in a truck is another matter.

Dave Evans

PS - for more info, Google Timken and check out their web site - they have a number of interesting pdf downloads for railroad wheel bearings.

--- In STMFC@..., "John Hagen" <sprinthag@...> wrote:

Dave,

I don't see how the immersion in oil could have much of affect on increased
resistance. Oil is less viscous than grease at all temperatures so I don't
understand how they would add resistance. Trucks use oil immersed bearing
for reliability and less resistance. I always thought (when I thought about
it which is all that often) that the reason railroads don't use oil bath
rollers bearings the susceptibility of the housing/reservoir to damage from
all the crap that ends up on the right of ways.



John Hagen




--- In STMFC@... <mailto:STMFC%40yahoogroups.com> , "Mike
Brock" <brockm@> wrote:

Well...what the hell...everyone else seems to have commented on some
part of
this subject so why not me?

From The Steam Locomotive by Ralph Johnson, Chief Engineer of Baldwin
Locomotive Works, 1942, "Roughly it may be said , that the ratio of
resistance in starting a car equipped with roller bearings, as compared
to
one equipped with solid bearings is eight to one in favor of the roller
bearing". "As the speed of the train increases the difference in
frictional
resistance between the two types of bearings decreases rapidly, and
above 10
mph the difference becomes very small. In cold weather the starting
resistance of a train with solid bearings is quite high and therefore
the
acceleration of a train equipped with roller bearings is aided very
materially". " As a general propostion it may be stated that, by the use
of
roller bearings, the journal friction will be reduced 50% at starting,
approximately 10% from 5 to 35 mph and nothing above 35 mph".

Reckon he knows anything?

What do I call non roller bearings? Depends upon how many beers I have
consumed.

Mike Brock
Mike,

I hope my latest post does not drive you beyond a six pack....

This seems like a good starting point for 1942. What surprised me from
reviewing the car builder's cyclopedia was the immersion of roller bearings
in oil. This would no doubt significantly increase the friction of roller
bearings.

There has been significant progress in reducing roller bearing friction
since then - not sure where things stood at the end of this group's era
(1960), but roller bearing friction today, at speed, is much less than the
JOURNAL bearings of old. Friction that results from trucks tracking through
curves is also reduced (by a combination of better bearings and better truck
geometries), such that the old curve compensation standard for laying out
right of way may be out of date (note - this is a theory based on some
analysis of a very complicated subject a few years ago that I am not going
to get into again - not worth my time.)

One 2003 engineering report I have from a prototype truck manufacturer
indicates that rolling resistance of modern freight car trucks on tangent
track is only 1.8 pounds per ton of car weight - without any speed
dependency. The increased car resistance with speed is now mostly
aerodynamic. Tapered roller bearings have come a long way.

Dave Evans







decals derailed

jerryglow2
 

I regret to inform you that effective immediately, I'm suspending all
decal sales. The mechanical issues with the printer at the print house
that does my printing continues to worsen making it impossible to
guarantee delivery in a timely manner. I will post here when the
situation is solved and sales resume.

I will do my best to fill any current open orders with decals on hand,
and refunds partial or full issued.

My web site will also contain notification when the situation improves
so check it occasionally.

--
Jerry Glow
The Villages FL
http://home.comcast.net/~jerryglow/decals/


Re: Weathering Lighter Colored Cars

atsfnut <michaelEGross@...>
 

Dear Charles and Group,

I've been reading with interest the postings about weathering lighter colored cars and, with respect to washes, wanted to share some of my experience.

To begin with, I wash with solvent-based paints, usually enamels (Model Master, Testors, etc.) or tube oils, because I find that acrylics dry too quickly for me to control their application. These are always applied over a fully cured acrylic matte finish which protects the factory paint and lettering.

Several types of treatments have been described in the postings. One is the attempt to provide an overall "fade" or bleached look to the factory paint. You may be familiar with modeler and author Pelle Søeborg, who accomplishes this by airbrushing a thinned solution of Model Master "sand" to his models.

I customarily use washes to give depth to a model—"shadows," if you will. This typically consists of a darker, sympathetic shade of the base color applied with a brush, then wiped away with cotton swabs, sponges, etc. Most is removed, but the residue of this wash settles into cracks, depressions and along rivet lines, providing visual interest. The philosophy for lighter cars is exactly the same as with darker cars: use a darker, harmonious version of the base color applied with a much greater proportion of thinner to paint—a "tinted thinner," if you will. By "harmonious," I mean that warm colors (gold, bronze, copper, brown, tan, yellow, red, orange, maroon, off-whites) are applied to warm colors, and cool colors (black, pure white, silver, blues, greens, grays and some purples) are applied to cool.

For a boxcar red model, I will typically wash with a darker version of that red: raw umber or burnt sienna, for example. For an orange or a yellow car, I might use something lighter: light yellow ochre, or a raw sienna. Again, something darker, but in harmony with the base color.

There are no "rules," as the amount and intensity of the wash is up to you. The guiding principle must always be harmony: a darker version of the base color makes an effective color-contrast wash.

Mind you, I use this type of wash only as a first step, and usually apply other weathering effects: atmospheric (rain, sun, etc.); terrestrial (dirt, soot, wheel-throw); and man-made (dings, scrapes, spills, etc.) only after applying the wash.

There are many ways to do this and many tools available for your use, but this is the method I use, and I trust it provides you with another set of options.

Cheers!

Michael Gross
La Cañada, CA

--- In STMFC@..., "Charles Hostetler" <cesicjh@...> wrote:

Good Evening,

My first three weathering tries were on basic black hoppers. I just finished weathering a PCCX hopper in the yellow scheme, hoping to get some experience with a lighter colored car before I tackle my Shake N Take Hormel reefers:

http://cnwmodeling.blogspot.com/2012/04/pccx-6401-6425-usra-twin-hopper.html


I think I found out that a lighter colored acrylic wash is necessary for application to a lighter colored car. The darker wash ended up looking "muddy" (and I don't mean that in a good way) before I scrubbed it off and lightened it up a lot. Would some of you with more experience be willing to comment on this observation?

Regards,

Charles Hostetler
Goshen, IN


Re: Roller Bearing advantage

John Hagen <sprinthag@...>
 

Dave,



I don't see how the immersion in oil could have much of affect on increased
resistance. Oil is less viscous than grease at all temperatures so I don't
understand how they would add resistance. Trucks use oil immersed bearing
for reliability and less resistance. I always thought (when I thought about
it which is all that often) that the reason railroads don't use oil bath
rollers bearings the susceptibility of the housing/reservoir to damage from
all the crap that ends up on the right of ways.



John Hagen




--- In STMFC@... <mailto:STMFC%40yahoogroups.com> , "Mike
Brock" <brockm@> wrote:

Well...what the hell...everyone else seems to have commented on some
part of
this subject so why not me?

From The Steam Locomotive by Ralph Johnson, Chief Engineer of Baldwin
Locomotive Works, 1942, "Roughly it may be said , that the ratio of
resistance in starting a car equipped with roller bearings, as compared
to
one equipped with solid bearings is eight to one in favor of the roller
bearing". "As the speed of the train increases the difference in
frictional
resistance between the two types of bearings decreases rapidly, and
above 10
mph the difference becomes very small. In cold weather the starting
resistance of a train with solid bearings is quite high and therefore
the
acceleration of a train equipped with roller bearings is aided very
materially". " As a general propostion it may be stated that, by the use
of
roller bearings, the journal friction will be reduced 50% at starting,
approximately 10% from 5 to 35 mph and nothing above 35 mph".

Reckon he knows anything?

What do I call non roller bearings? Depends upon how many beers I have
consumed.

Mike Brock
Mike,

I hope my latest post does not drive you beyond a six pack....

This seems like a good starting point for 1942. What surprised me from
reviewing the car builder's cyclopedia was the immersion of roller bearings
in oil. This would no doubt significantly increase the friction of roller
bearings.

There has been significant progress in reducing roller bearing friction
since then - not sure where things stood at the end of this group's era
(1960), but roller bearing friction today, at speed, is much less than the
JOURNAL bearings of old. Friction that results from trucks tracking through
curves is also reduced (by a combination of better bearings and better truck
geometries), such that the old curve compensation standard for laying out
right of way may be out of date (note - this is a theory based on some
analysis of a very complicated subject a few years ago that I am not going
to get into again - not worth my time.)

One 2003 engineering report I have from a prototype truck manufacturer
indicates that rolling resistance of modern freight car trucks on tangent
track is only 1.8 pounds per ton of car weight - without any speed
dependency. The increased car resistance with speed is now mostly
aerodynamic. Tapered roller bearings have come a long way.

Dave Evans


Re: Roller Bearing advantage - busted

devansprr
 

Looks like it will take some concentration on my part to stop using "friction bearings". Meant Journal bearings. Busted. Correction below

--- In STMFC@..., "Dave Evans" <devans1@...> wrote:

--- In STMFC@..., "Mike Brock" <brockm@> wrote:

Well...what the hell...everyone else seems to have commented on some part of
this subject so why not me?

From The Steam Locomotive by Ralph Johnson, Chief Engineer of Baldwin
Locomotive Works, 1942, "Roughly it may be said , that the ratio of
resistance in starting a car equipped with roller bearings, as compared to
one equipped with solid bearings is eight to one in favor of the roller
bearing". "As the speed of the train increases the difference in frictional
resistance between the two types of bearings decreases rapidly, and above 10
mph the difference becomes very small. In cold weather the starting
resistance of a train with solid bearings is quite high and therefore the
acceleration of a train equipped with roller bearings is aided very
materially". " As a general propostion it may be stated that, by the use of
roller bearings, the journal friction will be reduced 50% at starting,
approximately 10% from 5 to 35 mph and nothing above 35 mph".

Reckon he knows anything?

What do I call non roller bearings? Depends upon how many beers I have
consumed.

Mike Brock
Mike,

I hope my latest post does not drive you beyond a six pack....

This seems like a good starting point for 1942. What surprised me from reviewing the car builder's cyclopedia was the immersion of roller bearings in oil. This would no doubt significantly increase the friction of roller bearings.

There has been significant progress in reducing roller bearing friction since then - not sure where things stood at the end of this group's era (1960), but roller bearing friction today, at speed, is much less than the JOURNAL bearings of old. Friction that results from trucks tracking through curves is also reduced (by a combination of better bearings and better truck geometries), such that the old curve compensation standard for laying out right of way may be out of date (note - this is a theory based on some analysis of a very complicated subject a few years ago that I am not going to get into again - not worth my time.)

One 2003 engineering report I have from a prototype truck manufacturer indicates that rolling resistance of modern freight car trucks on tangent track is only 1.8 pounds per ton of car weight - without any speed dependency. The increased car resistance with speed is now mostly aerodynamic. Tapered roller bearings have come a long way.

Dave Evans


Re: Roller Bearing advantage

devansprr
 

--- In STMFC@..., "Mike Brock" <brockm@...> wrote:

Well...what the hell...everyone else seems to have commented on some part of
this subject so why not me?

From The Steam Locomotive by Ralph Johnson, Chief Engineer of Baldwin
Locomotive Works, 1942, "Roughly it may be said , that the ratio of
resistance in starting a car equipped with roller bearings, as compared to
one equipped with solid bearings is eight to one in favor of the roller
bearing". "As the speed of the train increases the difference in frictional
resistance between the two types of bearings decreases rapidly, and above 10
mph the difference becomes very small. In cold weather the starting
resistance of a train with solid bearings is quite high and therefore the
acceleration of a train equipped with roller bearings is aided very
materially". " As a general propostion it may be stated that, by the use of
roller bearings, the journal friction will be reduced 50% at starting,
approximately 10% from 5 to 35 mph and nothing above 35 mph".

Reckon he knows anything?

What do I call non roller bearings? Depends upon how many beers I have
consumed.

Mike Brock
Mike,

I hope my latest post does not drive you beyond a six pack....

This seems like a good starting point for 1942. What surprised me from reviewing the car builder's cyclopedia was the immersion of roller bearings in oil. This would no doubt significantly increase the friction.

There has been significant progress in reducing bearing friction since then - not sure where things stood at the end of this group's era (1960), but roller bearing friction today, at speed, is much less than the friction bearings of old. The reduction of friction in curves is also reduced (by a combination of better bearings and better truck geometries), such that the old curve compensation standard for laying out right of way may be out of date (note - this is a theory based on some analysis of a very complicated subject a few years ago that I am not going to get into again - not worth my time.)

One 2003 engineering report I have from a prototype truck manufacturer indicates that rolling resistance of modern freight car trucks on tangent track is only 1.8 pounds per ton of car weight - without any speed dependency. The increased resistance is now mostly aerodynamic. Tapered roller bearings have come a long way.

Dave Evans


Re: Truck bearings: Solid vs. RB

atsfnut <michaelEGross@...>
 

Much appreciate the clarification, Richard. I confess to being one of those who has used the term incorrectly, most likely because of its general usage. Proof again that if you tell an untruth often enough, it soon passes for the truth.

Cheers!

Michael Gross
La Cañada, CA

--- In STMFC@..., Richard Hendrickson <rhendrickson@...> wrote:

Several times lately I have noticed members of this group using the
term "friction bearings" to differentiate solid bearings from roller
bearings, despite objections on previous occasions from myself, Tony
Thompson, and others. The correct terminology for solid truck
bearings is "solid." "Plain bearings" is an acceptable alternative.
"Friction bearings" is wrong and misleading. All bearings have
friction, including roller bearings. "Friction bearing" was invented
as an advertising ploy by roller bearing manufacturers to imply,
incorrectly, that roller bearings were frictionless. In fact, though
roller bearings have much less starting resistance than solid
bearings, they have considerable friction which - as with other
bearings - increases as load and speed increase. The term "friction
bearings" was never adopted by railroad mechanical engineers, who
knew better; it does not appear in the dictionary section of any
edition of the Car Builders' Cyclopedia. So please, guys, don't
perpetuate the mistake of calling solid bearings "friction" bearings.

Richard Hendrickson



[Non-text portions of this message have been removed]


Re: Truck bearings: Solid vs. RB

devansprr
 

-- In STMFC@..., Anthony Thompson <thompson@...> wrote:

Dave Evans wrote:
The Mechanical Engineer's definition of "journal" is that portion of
the shaft that rotates within a bearing, AND the relative motion
between the two is sliding. There is NO sliding motion in a roller
bearing, so a roller bearing does not have a "journal".
I urge you to check any Car Builders Cyc in the period of this
list. The definitions for railroad use are quite clear.

Tony Thompson Editor, Signature Press, Berkeley, CA

Tony,

A fair point. My 1940 Car builders cyc is actually rather schizophrenic on this - if we want to adopt a clear naming convention based on the prototype of our era - I believe the term is "We're hosed"

In the cyc's definition of terms, there are two entries - one for Journal Bearings, and one for Roller bearings. There are also a WHOLE bunch of entries for "Journal xxx", but no "journal roller bearing", or "roller journal bearing". The definition of journal is the part of an axle or shaft on which the journal bearing rests.

The confusion is that the definition of Journal bearing includes rollers and balls (and then a reference to see roller bearings), along with the "traditional" journal bearing components.

Looking through the vendor documents, you can sense the source of the confusion. All of the roller bearing vendors used the term journal in their adds, but generally in reference to the "journal" not the bearing itself.

ASF promoted a roller bearing on the interior of the wheel that was supported by a fixed axle (good in curves since it will allow the wheels to rotate at different speeds.) Only the term roller bearing is used here - no journals.

Hyatt refers to the bearings as roller bearings only, although they were contained in a "journal box" and the "journal" part of the axle was where the bearing was pressed on. But their roller bearings are not referred to as journal bearings.

Timken uses the term roller bearing, or Timken bearing, but not journal bearing. They do stress the importance of a good journal box - mainly to maintain the oil supply - a feature no longer used today (just thin grease today, and only in select areas) (More on this later)

SKF seems to be the most confused - spherical bearings, spherical journal bearings, and even spherical roller journal bearing. Ughh..

Based on how the definitions and the ads are written, I would surmise that the industry knew it was confronting at least 50 years of long established journal bearing practice, and was caught between trying to promote a new and hopefully better technology while at the same time avoiding the perception that roller bearings were a major change that would obsolete equipment and the maintenance workforce (or require significant re-training).

Hence the conundrum.

But I would note that the terms "friction bearing", "plain" bearing and "solid" bearing do not appear in the cyclopedia. Anti-friction bearing does appear in some of the ads to describe roller bearings.

So while the prototype in the era may have been confused with the new technology and its terminology, we will either need to remain similarly confused, or adopt some form of standard convention.

As a mechanical engineer, I will stick with journal bearings (not to be confused with Journals, journal boxes, etc), and roller bearings. Plain, solid and friction are out for me. YMMV.

Dave Evans


Re: KCS Covered Hoppers series 29600-29649 and 29650-29749

Ed Hawkins
 

On Apr 26, 2012, at 4:15 PM, keyserlloyd wrote:

These four bay 40'-2" cars, built in 1946, were slab side all riveted construction. Possibly pre PS2 all welded cars? Originally delivered in black with white lettering. They had a "Load Limit cement-4'-4" below top of hatches". Can some one please tell me where these cars were loaded? Were they only loaded in cement? Were they on line cars only? I have a 1962 picture of a repaint that does not contain the cement load level line. I assure that by then they were in grain service.
Lloyd,
I cannot answer your questions about how and where these cars were used but will share some information about them.

I have 3 photos of these four-bay covered hopper cars. One is a Pullman builder's photo of 29621 from KCS 29600-29649, built 3-46, lot 5818 (photo also published in the 1949/51 CBC). The Pullman-Standard bill of materials for lot 5818 specified the cars were originally painted black with aluminum stencils. A 1" line about 3/4 the way up the car side has stencils above it stating "LOAD LIMIT FOR CEMENT 4' - 1 1/2" BELOW TOP OF HATCH".

The other two photos are KCS company photos of KCS 29671 and 29720. Both photos show a build date of 9-49. KCS 29650-29749 were built by GATC, builder's order no. 3013. They were shopped, repainted, and reweighed PG. (Pittsburg, Kansas) 3-53 and 6-54, respectively. The 29671 is painted black with aluminum (or possibly white) stencils while 29720 is painted gray with black stencils.

Interestingly, the lines on these two cars were drawn at different heights. The line on 29671 is lower, roughly 60% of the way up the side, but the stencils specify identical dimensions as the builder's photo. Perhaps the line was drawn in error (too low) since the stencils didn't change. The line on 29720 is at the same level as the Pullman builder's photo of 29621 with the same stencils.

The cubic capacity on the cars is 3190 cu. ft. In addition to hauling cement, it seems logical to me that the cars must have also been used for hauling lighter commodities in which the cubic capacity could be more fully utilized. For cement loading the cars were probably somewhere close to the purpose-built two-bay 1958 cu. ft. covered hoppers used extensively for hauling cement. The center of gravity would have been much lower on these cars when loaded to the line with cement. WIth 12 hatches and 8 outlets loading & unloading should have been faster than with conventional two-bay cars.
Regards,
Ed Hawkins


Re: Truck bearings: Solid vs. RB

Anthony Thompson <thompson@...>
 

Dave Evans wrote:
The Mechanical Engineer's definition of "journal" is that portion of the shaft that rotates within a bearing, AND the relative motion between the two is sliding. There is NO sliding motion in a roller bearing, so a roller bearing does not have a "journal".
I urge you to check any Car Builders Cyc in the period of this list. The definitions for railroad use are quite clear.

Tony Thompson Editor, Signature Press, Berkeley, CA
2906 Forest Ave., Berkeley, CA 94705 www.signaturepress.com
(510) 540-6538; fax, (510) 540-1937; e-mail, thompson@...
Publishers of books on railroad history


Re: Truck bearings: Solid vs. RB

devansprr
 

Sorry Tony,

The Mechanical Engineer's definition of "journal" is that portion of the shaft that rotates within a bearing, AND the relative motion between the two is sliding. There is NO sliding motion in a roller bearing, so a roller bearing does not have a "journal".

Some in the railroad industry may have retained the term "journal" to refer to the entire assembly, or the portion of the truck that is fastened to the outer portion of the bearing, or even to the portion of the shaft that the roller bearing is pressed onto (a legacy use, but incorrect), but roller bearings are not journal bearings.

Today, roller bearings are often included with the axle assembly - it is not something installed in the field. The tapered rollers roll between a "cone", typically press fit onto the axle, and the cup, which is the outer, stationary assembly that is mechanically fixed to the truck. Roller bearings are actually pairs of tapered roller bearings at each truck side frame (So two pairs per axle) so they can also react the thrust loads that result from curves (rated at about about 25% of the radial load). It is the need to react thrust loads, without creating excessive surface loads on the rollers, that contributes to the fine tolerances required for railroad roller bearings, and hence why they are an integral assembly that is pressed onto a portion of the axle with a very high precision outer diameter. Perhaps some still call this region of the shaft a journal, but technically that is incorrect.

Nowhere in Timken's railroad literature does the term "journal bearing" appear. There is, in one of their maintenance guides, two instances where they interchange the word axle and journal, but ONLY when they discuss machining the axle to the proper diameter. But as soon as they discuss installing the bearing, it is installed on the axle, not a journal. The only other appearance of journal refers to publications.

So roller bearing and journal bearing are the proper engineering terms to distinguish between the two bearing types.

The term "Plain" bearing does not appear in any of my engineering books.

Dave Evans
BSME
MSME
Lehigh University

--- In STMFC@..., Anthony Thompson <thompson@...> wrote:

Dave Evans wrote:
Gentlemen,
If we wish to be precise, then the term solid bearing is incorrect,
and in fact does not appear in engineering mechanics texts.
The bearings we are discussing are "journal" bearings, and they are
of the Hydrodynamic sub-type.
Nope. These bearings are journal bearings because they bear on
the axle journals. The journal is the part of the axle that the
bearings ride on. It does not matter whether they are roller bearings
or solid (or plain, if you prefer) bearings, they are all journal
bearings.


Tony Thompson Editor, Signature Press, Berkeley, CA
2906 Forest Ave., Berkeley, CA 94705 www.signaturepress.com
(510) 540-6538; fax, (510) 540-1937; e-mail, thompson@...
Publishers of books on railroad history


Roller Bearing advantage

Mikebrock
 

Well...what the hell...everyone else seems to have commented on some part of this subject so why not me?

From The Steam Locomotive by Ralph Johnson, Chief Engineer of Baldwin Locomotive Works, 1942, "Roughly it may be said , that the ratio of resistance in starting a car equipped with roller bearings, as compared to one equipped with solid bearings is eight to one in favor of the roller bearing". "As the speed of the train increases the difference in frictional resistance between the two types of bearings decreases rapidly, and above 10 mph the difference becomes very small. In cold weather the starting resistance of a train with solid bearings is quite high and therefore the acceleration of a train equipped with roller bearings is aided very materially". " As a general propostion it may be stated that, by the use of roller bearings, the journal friction will be reduced 50% at starting, approximately 10% from 5 to 35 mph and nothing above 35 mph".

Reckon he knows anything?

What do I call non roller bearings? Depends upon how many beers I have consumed.

Mike Brock


Re: Truck bearings: Solid vs. RB

John Hagen <sprinthag@...>
 

Very enlightening Dave and thanks for posting.



It would seem to me that the speed at which the oil layer would establish
itself would depend on how much weight was riding of the bearings. With the
weight of a loaded car versus that of an empty I think it would take a
higher speed to drag that oil completely around the bearing surface. And the
temperature would also effect it. In sub zero temps that oil is not going to
be easy to drag into that "squish" area.



I never really thought about all this but basically what has to happen the
lubricant must actually lift the weight of the car up off the bearing
surface. That fact that it even happens without an oil pump is somewhat
amazing to me. Here is a lesson for drivers. Even though your vehicles
engine has an oil pressures pump it takes a bit of time. Measured in
seconds, to get that pressure to the bearings. The colder the longer. That
is why all manufacturers recommend letting you engine idle for a bit before
moving off and not revving it even when not in gear.



If you have a relatively small car that can be easily pushed try pushing it
when it is fully warmed up. Then try it on a warm morning but before
driving. Lastly, wait for COLD weather and try pushing that now virtually
immobile block of icy metal. This will demonstrate just how resistant to
movement oil can become in frigid temps. Twenty-five years in the automotive
service business and I know the answers. It's a great thing to tell a
customer when he/she complains that the car gets poorer fuel mileage in cold
weather.



John Hagen



From: STMFC@... [mailto:STMFC@...] On Behalf Of Dave
Evans
Sent: Thursday, April 26, 2012 17:25
To: STMFC@...
Subject: [STMFC] Re: Truck bearings: Solid vs. RB





Gentlemen,

If we wish to be precise, then the term solid bearing is incorrect, and in
fact does not appear in engineering mechanics texts.

The bearings we are discussing are "journal" bearings, and they are of the
Hydrodynamic sub-type.

The term "anti-friction" bearing is applied to roller bearings and other
types of bearings where the main relative motion is rolling instead of
sliding.

I can understand why marketing types might then label Journal bearings
"friction" bearings, even if mechanical engineers never did.

Journal bearings use some form of lubrication between two sliding surfaces.
Hydrodynamic journal bearings draw lubricating oil into the bearing gap
using fluid mechanics. The lubricant is not under pressure (as it is in auto
engines, which use Hydrostatic journal bearings.)

From my engineering book:

"The film pressure is created by the moving surface itself pulling the
lubricant into a wedge shaped zone at a velocity sufficiently high to create
the pressure necessary to separate the surfaces against the load on the
bearing."

This is why the friction of hydrodynamic journal bearings can be so high
when they first begin to turn. They may first start with direct
metal-to-metal contact but even with a very thin oil film the drag can be
much higher than "normal". Since journal bearing friction is a function of
film thickness - the thinner the film, the higher the friction
(mathematically this friction is a function of one over the film thickness).
As speed increases the bearing is designed to induct more oil to create a
thicker film.

This is much different than roller bearings, and helps to explain why,
during the steam era, if the train got under a few mph and the locomotive
lacked the pull to accelerate, the train could just "grind" (figuratively,
not literally) to a halt. And it explains why steam era engineers didn't
walk out trains at very low speeds - better to keep the moving cars above
the speed that could lead to a sure stall as more cars were placed in motion
(and hence all of that slack action - a good reason for those buffered draft
gear and underframes).

So for steam era journal bearings, until the speed increased to a point
where the design film thickness was established, friction could actually
drop as speed increased. I do not know the "crossover" speed where drag
began to increase as speed increased. Conversely, this crossover speed was
also the speed where drag INCREASED as speed dropped. Perhaps it is in an
old railroad engineering book.

Makes one wonder if steam may have lasted a little longer if roller bearings
had been more widely applied - they are much easier to start and keep
rolling at low speeds, which was often a steam locomotive's greatest
challenge, and helps explain why steam locomotives pulling modern trains
under heavy loads seem to do so well - probably better than when they were
built.

This also explains why journal bearing cars appear to come to a sudden stop
in the last phase of coasting - they actually do stop quickly (think about
the implications for a journal bearing era hump yard.) As they slow, the
friction will increase significantly once the film begins to thin (and the
slower speed results in an even thinner film - so the friction rapidly
builds as the car comes to a stop). I bet hump rider's intuitively
understood this, even if they did not know the physics.

Richard is correct that once the steady state film thickness was established
(at some unknown, to me, speed) the friction increased with speed - but only
linearly, so the total friction per unit distance traveled was nearly
constant (no journal bearing fuel penalty for running faster - but there was
a fuel penalty for aerodynamic drag at higher speeds.) Note that friction
equals heat generation, so the high speed risk was that the heat generated
per unit time increased (but not per unit distance traveled), and it could
reach a point where the heat could not be rejected fast enough to the
atmosphere, and the oil would overheat, potentially resulting in loss of the
bearing film - and... Hot box)

And talk about Journal Bearing "hot boxes" - an older colleague at work once
told me stories of how when he was a kid, in Portage, PA (on the PRR main),
the kids use to take "those oily rags" out of the journal boxes in the
winter time to help start camp fires when they were outside playing ice
hockey. The innocence of youth....

Dave Evans

Nothing is ever fool proof, because fools are so ingenious ;-)

--- In STMFC@... <mailto:STMFC%40yahoogroups.com> , tyesac@...
wrote:

Richard, Pierre,

Right you are! If anybody thinks that solid bearings are obsolete
technology, think again. Anything driven by a crankshaft has solid bearings;
from a formula 1 race car to diesel locomotive. Properly lubricated, they're
a low resistance bearing that's able to tolerate heavy loads. A key issue
for the changeover for the railroads was that roller bearings have less
finicky lubrication requirements, typically only the roller cage requires
greasing at initial installation. Having large percentages of the freight
car fleet that doesn't require constant vigilance for oiling helped tip the
scales for the more expensive roller bearings.

Now if we could only get some model RR manufactures to drop the "friction
bearing" term.

Tom Casey


Thanks Richard, for that clarification. I've never been comfortable with
the "friction bearing" phrase myself and I've always wondered what the
correct term should be. In part because a solid bearing is closer to a
bushing than a bearing in my world of mechanical creations.
Pierre Oliver

--- In STMFC@... <mailto:STMFC%40yahoogroups.com> , Richard
Hendrickson <rhendrickson@> wrote:

Several times lately I have noticed members of this group using the
term "friction bearings" to differentiate solid bearings from roller
bearings, despite objections on previous occasions from myself, Tony
Thompson, and others. The correct terminology for solid truck
bearings is "solid." "Plain bearings" is an acceptable alternative.
"Friction bearings" is wrong and misleading. All bearings have
friction, including roller bearings. "Friction bearing" was invented
as an advertising ploy by roller bearing manufacturers to imply,
incorrectly, that roller bearings were frictionless. In fact, though
roller bearings have much less starting resistance than solid
bearings, they have considerable friction which - as with other
bearings - increases as load and speed increase. The term "friction
bearings" was never adopted by railroad mechanical engineers, who
knew better; it does not appear in the dictionary section of any
edition of the Car Builders' Cyclopedia. So please, guys, don't
perpetuate the mistake of calling solid bearings "friction" bearings.

Richard Hendrickson





-----Original Message-----
From: Pierre <pierre.oliver@...>
To: STMFC <STMFC@... <mailto:STMFC%40yahoogroups.com> >
Sent: Wed, Apr 25, 2012 7:49 pm
Subject: [STMFC] Re: Truck bearings: Solid vs. RB




Thanks Richard, for that clarification. I've never been comfortable with
the "friction bearing" phrase myself and I've always wondered what the
correct term should be. In part because a solid bearing is closer to a
bushing than a bearing in my world of mechanical creations.
Pierre Oliver

--- In STMFC@... <mailto:STMFC%40yahoogroups.com> , Richard
Hendrickson <rhendrickson@> wrote:

Several times lately I have noticed members of this group using the
term "friction bearings" to differentiate solid bearings from roller
bearings, despite objections on previous occasions from myself, Tony
Thompson, and others. The correct terminology for solid truck
bearings is "solid." "Plain bearings" is an acceptable alternative.
"Friction bearings" is wrong and misleading. All bearings have
friction, including roller bearings. "Friction bearing" was invented
as an advertising ploy by roller bearing manufacturers to imply,
incorrectly, that roller bearings were frictionless. In fact, though
roller bearings have much less starting resistance than solid
bearings, they have considerable friction which - as with other
bearings - increases as load and speed increase. The term "friction
bearings" was never adopted by railroad mechanical engineers, who
knew better; it does not appear in the dictionary section of any
edition of the Car Builders' Cyclopedia. So please, guys, don't
perpetuate the mistake of calling solid bearings "friction" bearings.

Richard Hendrickson





Re: Truck bearings: Solid vs. RB

Anthony Thompson <thompson@...>
 

Dave Evans wrote:
Gentlemen,
If we wish to be precise, then the term solid bearing is incorrect, and in fact does not appear in engineering mechanics texts.
The bearings we are discussing are "journal" bearings, and they are of the Hydrodynamic sub-type.
Nope. These bearings are journal bearings because they bear on the axle journals. The journal is the part of the axle that the bearings ride on. It does not matter whether they are roller bearings or solid (or plain, if you prefer) bearings, they are all journal bearings.

Richard is correct that once the steady state film thickness was established (at some unknown, to me, speed) the friction increased with speed - but only linearly, so the total friction per unit distance traveled was nearly constant (no journal bearing fuel penalty for running faster - but there was a fuel penalty for aerodynamic drag at higher speeds.)
Tests showed that at speeds like 30 or 40 mph, the difference in rolling resistance between plain and roller bearings was negligible. The big difference, and as Dave say, a very important difference for steam power, was at starting speeds.

Note that friction equals heat generation, so the high speed risk was that the heat generated per unit time increased (but not per unit distance traveled), and it could reach a point where the heat could not be rejected fast enough to the atmosphere, and the oil would overheat, potentially resulting in loss of the bearing film - and... Hot box)
This is probably true, but my impression from reading and from talking to railroaders of that era is that hotboxes occurred because the waste would get snagged or bunched and get into the bearing surface, and presto, much reduced lubrication. This could and did happen at quite modest speeds. Whether really high-speed trains ever had hot boxes from speed alone, I don't know, but if so, one would expect a LOT of the cars in such a train to have the problem.

Tony Thompson Editor, Signature Press, Berkeley, CA
2906 Forest Ave., Berkeley, CA 94705 www.signaturepress.com
(510) 540-6538; fax, (510) 540-1937; e-mail, thompson@...
Publishers of books on railroad history

88501 - 88520 of 197042