Freight Car Distribution on smaller RRs


Garth G. Groff <ggg9y@...>
 

Mike,

Consider that two of the same cars could mean your are twice as serious a prototype modeler than the rest of us!

Kind regards,


Garth G. Groff

Mike Brock wrote:


. . . All of this is freightening, of course, but trivial compared to the fact that I have two [ 2 ] UP CA-1 cabooses with the same number. Geeez. That would do it. Can you imagine? I painted and numbered a brass CA-1 and Walthers produced their model yrs later...with the same number. Reckon the police will excuse me? Hmmm. Yep, that's what I figure also...

Mike Brock


Dave Nelson
 

As a reminder, the hypothesis that Tim and I asserted always was qualified:

Ordinary, **foreign** road boxcars. Tim later suggested ordinary foreign
road flatcars were the same. Post WWII **mainline** trunk routes. That the
ratio of home to foreign road boxcars would vary along w/ economic
conditions (i.e., there is not one magic ratio everyone should use as
everyone has a different time period in mind). And last, but not least,
the sample size had to be large... As in at least 1000 foreign road boxcars.
Tim and I were studying railroads, not model railroads. Continuing, I
always argued against the inclusion of Canadian marked cars... Or if
included, to set their railroads contribution to distributed fleet at 10% so
as to match the FACT that only 10% of home road cars loaded in Canada were
sent south of the border and that the law required them to be returned to
Canada quite directly.

Not expressed, but IMO a reasonable addition, would be to add something to
take into account the complete ownership of one road by another, such as the
SN by the WP, the T&NO by the SP, and yes, perhaps even the CV by the CN.

All of that slices out of the picture a lot of locations and in some cases,
a lot of cars (i.e., counting CN cars on the CV as home road).

So right off the bat, Jack Burgess and his YV were out of scope. As were
all the PRR boxcars in Enola Yard. I'm not familiar w/ the Ball Line
Route... But I want to ask: Were those cars part of the common carrier fleet
or were they private road cars? One would expect a different movement
pattern for the later.

In recent years I have done futher analysis on the Western Pacific traffic
and seen a very distinct pattern of a large number of loaded boxcars
terminating in the SF Bay Area and correspondingly fewer outbounds.
Slightly more than a 2:1 ratio. Thinking on that fact led me to realize the
WP had little need for storing ordinary, home road boxcars in protective
service in this area as they were "blessed" w/ a a generous supply provided
by everyone else. Which led to the notion that in areas where the
opposite traffic conditions were true... Such, places like, say, Modesto,
CA, the opposite conditions for protective service would also be true. If
true, then there may have been a fair number of SP and ATSF boxcars sitting
aound in and near Modesto... from which some could have been loaned to the
YV when asked for.

Moving on... As for the interesting analysis of how to manage a modeled
freight car fleet... I agree the correct procedure is to reserve some
portion of the foreign road boxcars -- I thought in the 10-20% range of the
owners nominal count of on-layout foreign road cars, for double or tripple
the number of cars that percentage calculated to, but bearing the marks of
smaller roads, cycling them in and out regularly. The only problems I see
with that approach is storage, extra handling, and the bother of having to
do it. But the theory is sound and the variety it provides, both visually
and in the pleasure of collecting them, could still make it worthwhile.

Dave Nelson


Charlie Vlk
 

To build on Gene's observation, this is one of the objections I have to the Car Card Pocket / Waybill system as it is supposed to be used (waybills don't stay with the Car Card Pocket but are cycled through available appropriate car types.... but many don't ever leave the pocket and at best the car cycles through the four available waybills).
Seems to me that because of the route and traffic originating on railroads and the relationships between roads car usage is not really random. Certain actors get the parts more often than others. Selection of roadnames for "foreign" cars is more based on where inbounds originate than any mathematical or statiscial scheme. Yes, there are exceptions because of the intent of the interchange rules, but you are more likely to see a GN, NP or CB&Q car with lumber inbound to a road that has freindly connections to the Q than a Milwuakee road car. Not that you can't justify a Ribside Car Co. or Fox Valley MILW ribside on your layout, it just wouldn't be as common.
So I don't think you need the speration of Car Card and Waybill.... the role any given car plays should not be random.
It seems to me that with computers it isn't necessary to have the additional bulk of the car card pocket.... the "scripts" ... waybills .... and the car information can be printed and cut an pasted together on one card. The only problem is how to indicate the completion of a waybill on a card that has several on it (including delivery of empty cars to an online shipper for loading or forwarding to the car's owner in compliance (or total violation of) the interchange rules..... having the conductor mark the date of delivery after the waybill line can take care of that and eliminates the need for the layout owner to "flip" waybills in between sessions.
Anyone using such a setup???
Charlie Vlk

----- Original Message -----
From: Gene Green
To: STMFC@yahoogroups.com
Sent: Thursday, February 05, 2009 11:12 AM
Subject: [STMFC] Re: Freight Car Distribution on smaller RRs


It seems to me that the various mathematical or statistical schemes
have one starting in the wrong place.

On most model railroads there are loads that originate on the modeled
portion, loads that have a destination on the modeled portion and loads
that simply pass through the scene. (Jack Burgess' Yosemite Valley and
similar RRs that only connect with the rest of the world at one point
would not have that latter category, I suppose.)

First, I think, one should determine what gets shipped from or
delivered to points on the modeled portion. Those loads will
necessarily suggest, and in some cases demand, a certain type of car.
Next determine how much is shipped or received. Now you can determine
the number of the various types of cars needed.

Now one has the information needed to start using a mathematical or
statistical scheme ONLY IF better information is not available.

Gene Green

.


Jack Burgess
 

Gene wrote:

It seems to me that the various mathematical or statistical schemes
have one starting in the wrong place.

On most model railroads there are loads that originate on the modeled
portion, loads that have a destination on the modeled portion and loads
that simply pass through the scene. (Jack Burgess' Yosemite Valley and
similar RRs that only connect with the rest of the world at one point
would not have that latter category, I suppose.)

First, I think, one should determine what gets shipped from or
delivered to points on the modeled portion. Those loads will
necessarily suggest, and in some cases demand, a certain type of car.
Next determine how much is shipped or received. Now you can determine
the number of the various types of cars needed.

Now one has the information needed to start using a mathematical or
statistical scheme ONLY IF better information is not available.
That is exactly correct Gene, especially for railroads like the YV and
others that didn't have "through" traffic. Some of that "better information"
is obviously photos and there are numerous photos of YV trains with gondolas
so I bought many years ago when Westerfield first released kits for them.
Years later, I discovered that they were used to ship zinc concentrates
beginning in...ah...1944. That is why Mark Piece was able to buy a
Westerfield Milwaukee #307802 gondola from me last year....<g>

Jack Burgess
www.yosemitevalleyrr.com


Tim O'Connor
 

Jack was the zinc inbound, or outbound? If outbound, do
you know where it went? I suppose if inbound in a Milwaukee
gondola then it could have come from Idaho... and if it
was inbound, what industry used it?

Tim O'

That is exactly correct Gene, especially for railroads like the YV and
others that didn't have "through" traffic. Some of that "better information"
is obviously photos and there are numerous photos of YV trains with gondolas
so I bought many years ago when Westerfield first released kits for them.
Years later, I discovered that they were used to ship zinc concentrates
beginning in...ah...1944. That is why Mark Piece was able to buy a
Westerfield Milwaukee #307802 gondola from me last year....<g>

Jack Burgess
www.yosemitevalleyrr.com


Jack Burgess
 

Tim wrote:
Jack was the zinc inbound, or outbound? If outbound, do
you know where it went? I suppose if inbound in a Milwaukee
gondola then it could have come from Idaho... and if it
was inbound, what industry used it?

Tim O'
It was outbound from Merced Falls/the YV and was considered essential to the
war effort...they shipped 115 carloads in the first months of 1944. I don't
know where it went. Switch lists from August 1945 show gondolas from the
C&O, D&RGW, Erie, IC, PMcK&Y, and SP being used for this purpose. But it is
outside my modeling year so I had to get rid of my gondolas, whether they
were from an appropriate railroad or not...

Jack Burgess
www.yosemitevalleyrr.com


Steve Lucas <stevelucas3@...>
 

Gene--

IMHO, there is no one STMFC distribution model that can be universally
applied by all STMFC modellers. Each has its own merits. But it's
said that when the only tool that one has is a hammer, every problem
becomes a nail.

STMFC layout owners could use primary sources (i.e. switch lists,
wheel reports) for car distribution--if they were available. Of
course, for most this is not the case. But to rely on any one model
alone is fraught with peril. I like the N-G (seems to be mostly
overhead traffic on a transcon piece of the UPRR) data, but can I
really use it in MY STMFC layout roster? I'm more inclined to
consider (and favour the study of to determine my STMFC roster) what
was shipped/received/overhead traffic in my prototype line segment.

And this discussion makes me realise that those GA, D&H, and B&M
boxcars are not going to be seen on my 1956 Eastern Ontario layout too
often!

Steve Lucasv

--- In STMFC@yahoogroups.com, "Gene Green" <bierglaeser@...> wrote:

It seems to me that the various mathematical or statistical schemes
have one starting in the wrong place.

On most model railroads there are loads that originate on the modeled
portion, loads that have a destination on the modeled portion and loads
that simply pass through the scene. (Jack Burgess' Yosemite Valley and
similar RRs that only connect with the rest of the world at one point
would not have that latter category, I suppose.)

First, I think, one should determine what gets shipped from or
delivered to points on the modeled portion. Those loads will
necessarily suggest, and in some cases demand, a certain type of car.
Next determine how much is shipped or received. Now you can determine
the number of the various types of cars needed.

Now one has the information needed to start using a mathematical or
statistical scheme ONLY IF better information is not available.

Gene Green


Gatwood, Elden J SAD
 

Charlie;



Funny that you brought that up!



I have had that same problem with standardized car requirements/waybills on
my layout. It just didn't seem to replicate what I thought was going on in
real life.



I switched to an approach in which each industry generates a "demand" (car
number and type) each day, based on what they needed in empties and pick-ups.
A given entry on one day at USSteel might be "Need four MT 8K tank cars (ICC
103), twenty MT 70-t hoppers (or equivalent), and twelve clean MT gondolas
(two of which are 65'). Pick up all loaded gons, hoppers, and tank cars for
routing to Shire Oaks for classification". Only one card in many specifies
that they need two tanks of sulphuric acid, or a box car with electrical
parts for the mill. I can split that order up in two, for a morning and
afternoon local, so I can also serve other customers on that run (I am also
leaving out incoming scrap, flux stone, etc., but you get the drift).



In the winter months when the rivers freeze over and on-site coal supply gets
thin, one might them route coal into USS. There should be seasonal
variations, I guess.



A lumber yard might get more specific, since they need filled cars from
certain locations, like "Empire Lumber requires one load (50' box) of
interior-grade lumber, which is supplied from the Pacific Northwest (another
"pull" might specify southern pine). That way I get plausible cars with
imaginary or actual loads appropriate for that customer. Thus, for that
order I need an NP, SP&S, or GN 50' box car, or maybe a local road car that
has been sent back to me (not as common since most of those 50-footers on the
PRR would not have been going out that way).



I also have customers/industries that require certain loads once in a blue
moon, like a transformer at a power plant, or a flat car with a dozer at a
team track. Most of those demands are blank, then (team tracks were only
sporadically used by my date).



I then have to scare up cars out of staging to fill each train.



Large industries have a whole bunch of potential entries. Some small
businesses have only a few possible entries. Each of these lists is based on
research of the prototype industry, although some small ones are still
speculative. Specific loads are then loaded (or imaginary loaded in the case
of box cars, covered hoppers, tanks) into cars that have a specific purpose.



This requires me to write down the demands, obtain cars to fill it (via the
staging of trains), and then write up a switch list. I do not have to keep a
big stack of car cards (which drove me crazy), and my switch lists are a
one-time affair (although I kept some).



Yes, some cars appear much more frequently than others, due to demand issues.
If someone needs a 40' box, then most any 40' box could be sent from staging,
but if they need a real oddball (rarely), like a tank car in dedicated resin
service, they may have to wait until they become available.



This way of doing things allows me to generate lists of cars to be set out
(and pick up orders), in the sequence that makes blocking easy, and filling
out of switch lists easy, too.



No more waybills, just imaginary phone calls from customers, random event
cards, and easy switch lists.



Just another way to do it, I suppose.



Elden Gatwood



________________________________

From: STMFC@yahoogroups.com [mailto:STMFC@yahoogroups.com] On Behalf Of
Charlie Vlk
Sent: Thursday, February 05, 2009 12:39 PM
To: STMFC@yahoogroups.com
Subject: Re: [STMFC] Re: Freight Car Distribution on smaller RRs



To build on Gene's observation, this is one of the objections I have to the
Car Card Pocket / Waybill system as it is supposed to be used (waybills don't
stay with the Car Card Pocket but are cycled through available appropriate
car types.... but many don't ever leave the pocket and at best the car cycles
through the four available waybills).
Seems to me that because of the route and traffic originating on railroads
and the relationships between roads car usage is not really random. Certain
actors get the parts more often than others. Selection of roadnames for
"foreign" cars is more based on where inbounds originate than any
mathematical or statiscial scheme. Yes, there are exceptions because of the
intent of the interchange rules, but you are more likely to see a GN, NP or
CB&Q car with lumber inbound to a road that has freindly connections to the Q
than a Milwuakee road car. Not that you can't justify a Ribside Car Co. or
Fox Valley MILW ribside on your layout, it just wouldn't be as common.
So I don't think you need the speration of Car Card and Waybill.... the role
any given car plays should not be random.
It seems to me that with computers it isn't necessary to have the additional
bulk of the car card pocket.... the "scripts" ... waybills .... and the car
information can be printed and cut an pasted together on one card. The only
problem is how to indicate the completion of a waybill on a card that has
several on it (including delivery of empty cars to an online shipper for
loading or forwarding to the car's owner in compliance (or total violation
of) the interchange rules..... having the conductor mark the date of delivery
after the waybill line can take care of that and eliminates the need for the
layout owner to "flip" waybills in between sessions.
Anyone using such a setup???
Charlie Vlk

----- Original Message -----
From: Gene Green
To: STMFC@yahoogroups.com <mailto:STMFC%40yahoogroups.com>
Sent: Thursday, February 05, 2009 11:12 AM
Subject: [STMFC] Re: Freight Car Distribution on smaller RRs

It seems to me that the various mathematical or statistical schemes
have one starting in the wrong place.

On most model railroads there are loads that originate on the modeled
portion, loads that have a destination on the modeled portion and loads
that simply pass through the scene. (Jack Burgess' Yosemite Valley and
similar RRs that only connect with the rest of the world at one point
would not have that latter category, I suppose.)

First, I think, one should determine what gets shipped from or
delivered to points on the modeled portion. Those loads will
necessarily suggest, and in some cases demand, a certain type of car.
Next determine how much is shipped or received. Now you can determine
the number of the various types of cars needed.

Now one has the information needed to start using a mathematical or
statistical scheme ONLY IF better information is not available.

Gene Green

.


Dave Nelson
 

Gene Green wrote:
It seems to me that the various mathematical or statistical schemes
have one starting in the wrong place.

On most model railroads there are loads that originate on the modeled
portion, loads that have a destination on the modeled portion and
loads that simply pass through the scene.
First, I think, one should determine what gets shipped from or
delivered to points on the modeled portion.

I'll repeat myself: Tim and I were doing analysis of railroads, not model
railroads. Our hypothesis on the distribution of ordinary boxcars was for
real world data. That it might have some bearing on what an owner of a
model railroad could do has always been a bit problematic, if, for no other
reason, the huge reduction in the sample size. Modelers also often choose
to over-represent local movements...and area limits usually mean a gross
reduction in the representation of urban mfg areas...or even single sites.
And of course the cost of obtaining and using a foreign road boxcar fleet
large that is large enough to represent a national sample is another issue.
All of which adds to the difficulty of applying the hypothesis.

OTOH, for those few of us doing V-Scale -- that is computer sim railroading
-- we have the opportuity to do urban sites 1:1 (as I happen to be
modeling), to run 60, 70, 80 car freights (as I do), and to run over an
entire division of 100+ miles, with each town represented in full (as I
happen to be modeling). IOW, the difficulties of applying the distribution
to this method of modeling a setting disappears entirely.

All that said, I'll still stick to the premise that, absent historical data
for the site being modeled, the distribution model we offered is a pretty
decent place to start, whether one is modeling in plastic, resin, or
brass... or pixels.

Dave Nelson


Mike Brock <brockm@...>
 

Dave Nelson writes:

"I'll repeat myself: Tim and I were doing analysis of railroads, not model
railroads. Our hypothesis on the distribution of ordinary boxcars was for
real world data. That it might have some bearing on what an owner of a
model railroad could do has always been a bit problematic, if, for no other
reason, the huge reduction in the sample size."

One thing that I have been arguing for is that the process one chooses to develop a box car fleet [ other fleets for other types of cars will be needed ] is that such a fleet needs to be capable of producing trains that match...with compression...actual trains. My conception of the N-G theory is that it shows box car populations over a very long time period...perhaps a yr. The problem I have is, will it address train consists?

Consider: I model only a tiny part of Sherman Hill and only about 3 hrs of traffic during one op session. 8 frt trains in all. I compress both the layout and the frt trains...from 75 to 30 cars. About 100 box cars....or 12 per train if they were applied equally which they were not. Using the % of the entire box car fleet, I should have 4 SP box cars. However, in order to model the infamous X4005 train with its 36 SP box cars...very close to 50% of the known train...I would need 15 SP box cars [ 50% of a 30 car train ]. To do that and stay within the N-G envelope of 4% of the national fleet, I would need 375 box cars. But...I will need more SP box cars to populate other trains so I'll go with 20 SP box cars. I now need 500 box cars. The question then is...how do I apply these 500 box cars to my 8 frt trains and their average of 12 per train? In any session the number of box cars should be about 100...leaving 400 in their boxes.

What does this do for the MWR car? Well, nothing. The 1953 ORER shows 100 MWR box cars. For me to have one MWR box car and match the N-G data base, I would need 7400 box cars. Anyone think I'll make it? Incidentally, using the 500 box car data base, I could not use a box car if a RR had less than 1480 box cars. Whew. SP&S barely makes it in. Tucson, Cornelia, and Gila Bend with their 3 cars missed the cut along with the Montana, Wyoming & Southern...which might be over represented due to their close proximity to the UP except for the fact that they had no box cars.

BTW, will I have to run 7399 box cars before the MWR car can show? Of course not. It might be the first...or 640th...car. However, you can also toss 24 7's in a row at a crap table in a Las Vegas Casino except for the fact that, after the 12th such toss, your toss might be a bit off course since your fingers...among other items...will all be broken. Still...there is no reason why...

Mike Brock



Yes. Modeling the UP on Sherman Hill over a three hour time period with its 35 frt trains doesn't match well with, for example, a yr's worth of data. Then, compress the 8 trains by 60%...from about 75 cars to 30.

my 100 box cars, I cannot generate a
compressed version of X4005 and its 36 SP box cars. I mean...compressing by
60%, I still need 14 SP box cars and the SP national % of 4% only gives me 4
of my 100 total not allowing that. I would, in fact, need 350 box cars to
give me enough to produce the train in question. And, since I would need
other SP box cars in frt trains...say 20 in total...I would need about 500
box cars. In that case, I would have to spread the cars...do op sessions
with different cars. The trouble with that is that I cannot just randomly
select cars. I still only have 8 frt trains and I can only apply about 1/5
of the fleet to the session.

As is obvious, model RRs compress everything. Compressing the box car fleet
will eventually

Continuing, I
always argued against the inclusion of Canadian marked cars... Or if
included, to set their railroads contribution to distributed fleet at 10% so
as to match the FACT that only 10% of home road cars loaded in Canada were
sent south of the border and that the law required them to be returned to
Canada quite directly.

Not expressed, but IMO a reasonable addition, would be to add something to
take into account the complete ownership of one road by another, such as the
SN by the WP, the T&NO by the SP, and yes, perhaps even the CV by the CN.

All of that slices out of the picture a lot of locations and in some cases,
a lot of cars (i.e., counting CN cars on the CV as home road).

So right off the bat, Jack Burgess and his YV were out of scope. As were
all the PRR boxcars in Enola Yard. I'm not familiar w/ the Ball Line
Route... But I want to ask: Were those cars part of the common carrier fleet
or were they private road cars? One would expect a different movement
pattern for the later.

In recent years I have done futher analysis on the Western Pacific traffic
and seen a very distinct pattern of a large number of loaded boxcars
terminating in the SF Bay Area and correspondingly fewer outbounds.
Slightly more than a 2:1 ratio. Thinking on that fact led me to realize the
WP had little need for storing ordinary, home road boxcars in protective
service in this area as they were "blessed" w/ a a generous supply provided
by everyone else. Which led to the notion that in areas where the
opposite traffic conditions were true... Such, places like, say, Modesto,
CA, the opposite conditions for protective service would also be true. If
true, then there may have been a fair number of SP and ATSF boxcars sitting
aound in and near Modesto... from which some could have been loaned to the
YV when asked for.

Moving on... As for the interesting analysis of how to manage a modeled
freight car fleet... I agree the correct procedure is to reserve some
portion of the foreign road boxcars -- I thought in the 10-20% range of the
owners nominal count of on-layout foreign road cars, for double or tripple
the number of cars that percentage calculated to, but bearing the marks of
smaller roads, cycling them in and out regularly. The only problems I see
with that approach is storage, extra handling, and the bother of having to
do it. But the theory is sound and the variety it provides, both visually
and in the pleasure of collecting them, could still make it worthwhile.

Dave Nelson



All of which adds to the difficulty of applying the hypothesis.

OTOH, for those few of us doing V-Scale -- that is computer sim railroading
-- we have the opportuity to do urban sites 1:1 (as I happen to be
modeling), to run 60, 70, 80 car freights (as I do), and to run over an
entire division of 100+ miles, with each town represented in full (as I
happen to be modeling). IOW, the difficulties of applying the distribution
to this method of modeling a setting disappears entirely.

All that said, I'll still stick to the premise that, absent historical data
for the site being modeled, the distribution model we offered is a pretty
decent place to start, whether one is modeling in plastic, resin, or
brass... or pixels.

Dave Nelson


Dave Nelson
 

Mike Brock wrote:

Yes. Modeling the UP on Sherman Hill over a three hour time period
with its 35 frt trains doesn't match well with, for example, a yr's
worth of data.
I have never said a year long sample was required. I have always suggested
that a minimum of 1000 foreign road boxcars be counted and always felt more
comfortable w/ something closer to 1500. On some secondary line, seeing
1000 foreign road boxcars might take a rather long time, tho I still think a
year is way too long. On Sherman Hill, I suspect 1000 foreign road cars
would be seen in days.

Moving on, Mike, you continue to toss out the argument that since your data
has 1 train w/ a large number of SP boxcars in it that the distribution
hyposthesis isn't very useful. I have countered numerous times that 1) one
train does not make a sample and 2) the distribution hypothesis has nothing
whatsoever to say about the composition of a single train. I will fall
back, once again, on my Yoplait Yogurt in the shopping car example: I do not
purchase Yoplait at regular prices (tho my daughter may slip in one or two
when I'm not looking); However when they are half off I but a whole lot of
them. The composition of my carts therefore varies considerably when
examined individually but the average number of yoplaits I buy over numerous
trips is probably pretty constant over time if enough trips are recorded and
analyzed.

What does this do for the MWR car? Well, nothing. The 1953 ORER shows 100
MWR box cars. For me to have one MWR box car
and match the N-G data base, I would need 7400 box cars. Anyone think I'll
make it? Incidentally, using the 500 box car data base, I
could not use a box car if a RR had less than 1480 box cars. Whew. SP&S
barely makes it in. Tucson, Cornelia, and Gila Bend with
their 3 cars missed the cut along with the Montana, Wyoming &
Southern...which might be over represented due to their close proximity
to the UP except for the fact that they had no box cars.
That is all correct. Which is why Hendrickson was hyperventilating earlier
today about absurdites. Fortunately, yours is a hobby, not a job, so if you
want to enjoy a MWR car, go ahead. Just keep it out of sight when Richard
visits. 8-) Or leave it over on the shelf in a nice display, where it
probably belongs all of the time.

Let me return to discuss a point I mentioned earlier today, which is,
really, which hobby: The problems most often raised on this subject are the
problems of (physical) model railroads, not of the distribution hypothesis
itself (that does have objections but they're mentioned less often). I
operate a (virtual) model railroad and can have many hundreds of 60, 70, 80
car consists composed, in total, of thousands of individual cars. My
constraint is the limited availablity of models, not the number of them (and
certainly not the cost... As they are all free), and that makes for a very
big difference in the utility of the distribution hypothesis.

Dave Nelson


devansprr
 

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


Consider: I model only a tiny part of Sherman Hill and only about 3
hrs of
traffic during one op session. 8 frt trains in all. I compress both the
layout and the frt trains...from 75 to 30 cars. About 100 box
cars....or 12
per train if they were applied equally which they were not. Using
the % of
the entire box car fleet, I should have 4 SP box cars. However, in
order to
model the infamous X4005 train with its 36 SP box cars...very close
to 50%
of the known train...I would need 15 SP box cars [ 50% of a 30 car
train ].
To do that and stay within the N-G envelope of 4% of the national
fleet, I
would need 375 box cars. But...I will need more SP box cars to populate
other trains so I'll go with 20 SP box cars. I now need 500 box
cars. The
question then is...how do I apply these 500 box cars to my 8 frt
trains and
their average of 12 per train? In any session the number of box cars
should
be about 100...leaving 400 in their boxes.

What does this do for the MWR car? Well, nothing. The 1953 ORER
shows 100
MWR box cars. For me to have one MWR box car and match the N-G data
base, I
would need 7400 box cars.

Mike Brock
Mike,

One way to use the N-G distribution model is to assess "plausibility"
for the presence of foreign road box cars on your layout. Needing one
train with 15 SP box cars doesn't instantly drive you into a huge box
car fleet. But unless the train ran several times a day, it makes a
strong case for letting the X4005 train stay in staging some days, and
perhaps fiddling the other box cars in that train. If you want to
emulate N-G, then I would simply segregate the SP cars dedicated to
this train from the rest of your fleet balance targets. So now you
need 15 SP cars for X4005, and 100 for the rest of your trains to
maintain N-G.

To my thinking, the intent of N-G is make a model railroad visit more
like a stop along the prototype's track. If you randomly stoped along
sherman hill in your era for 3 hours (more if you run a fast clock),
would you expect to see X4005 every visit? IF yes - run it every session.

As for the MWR car, same concept, how may 3 hour visits to sherman
hill before you spot it? One, ten, one hundred? Stats would suggest it
would be pretty infrequent. Same for the Ann Arbor, D&H and other
small roads (although they would appear much more often than the MWR,
but certainly these roads would not be seen every visit).

My lessons learned from this thread are:

1) N-G should apply to mainline trunk routes where the nation's
traffic is traversing a layout.

2) N-G applies to general merchandise deliveries from staging to
almost any industry where captive cars were not used, for most layouts
that received traffic from around the country.

3) It is very doubtful that N-G applies to empties delivered to small
branch lines by a larger road. When/where MTs were in surplus the
large road might send what would take them the longest to get rid of.

4) N-G may apply to MT box cars passing across a layout. It is
doubtful, depending on the era and location, that it would apply to
MTs arriving from staging for use at a specific on-layout yard that
was collecting MT's for distribution.

5) It DOES NOT apply to branch lines, or even medium sized lnes that
were not "trunking" the nation's traffic, in part because some (or
many) cars may be in captive service.

6) Having cars from small roads is perfectly acceptable - but they
should be fiddled in - it could be on a dice roll, or more analytic.
It seems that having an extra 30-60 box cars from smaller lines (and
some of these may be well known lines for a smaller fleet), is all
that is required to provide some sense of "randomness" to trains
entering the layout from staging.

7) It may be worth creating three pools - one of the dominant road's
cars, where nearly all are used all the time (assuming the layout can
handle your collection), one from lines that appear less then every
session, but were numerous. Depending on the extent of your
collection, 20-50% of these cars would be fiddled in each session. The
third pool would be the rarities (e.g. MWR on your UP mainline). If
you had 20 of these cars, you might randomly draw two per op session.

We need to ponder if some of the "attraction" to the rare car is, in
fact, because they were spotted so rarely on the prototype. I would
guess that when 50% of the WWII fleet was owned by 11 roads, spotting
the rare car would be a memorable event. But if you rail-fanned
sherman hill, based on your conductors reports, and saw 8 trains go
by, just how many of the cars would be from fleets smaller than say
the 20th road (C&O)? N-G would suggest that 25% of the cars would be
from these "smaller" lines (SOO, WAB, Erie, N&W, SAL, PM, GTW, RDG,
ACL, SAL, NYNH, DL&W, and over 100 others) Yet the 12 lines listed
have 100 times as many box cars as MWR.

I think the concept has some very positive merit. The good news is
that having 50% of your fleet from the 11 major roads is probably
pretty easy to accomplish, unless your fleet is primarily resin, in
which case I think you can do whatever you want ;-)

And it would not take a large fleet of cars from smaller roads to
create a "prototypical" sense of the occasional rare car passing
through your layout.

The one down side to this is that you need to be able to fiddle your
trains in staging so you can provide a prototypical sense of
"randomness" (I hate to breach the subject of rare car classes and how
often they should appear... Nevermind.)

The interesting finding is that because 50% of the boxcar fleet was in
11 roads, the "fiddle" pools do not need to be huge - 30-60 cars
depending on the size of the layout and the length of the PP's memory
(don't let them collect on-layout wheel reports!) And it is quite
reasonable to run that MWR car once every few sessions. Just don't put
it in a string of D&H, B&M, D&LW, AA, and RDG box cars, or no one may
notice it!

Dave Evans


Mike Brock <brockm@...>
 

Dave Evans writes:

"One way to use the N-G distribution model is to assess "plausibility"
for the presence of foreign road box cars on your layout. Needing one
train with 15 SP box cars doesn't instantly drive you into a huge box
car fleet."

Right. I could simply strongly over weight the number of SP box cars in order to be able to generate X4005. Also, the other data shows a much greater representation of SP box cars so it would not be a problem. The 1956 box car data [ 18 trains ] shows:

UP: 157
PRR: 48
NYC: 45
SP: 43
Milw: 22
CNW: 17
GN: 17
SR: 13
B&O:13
NP: 13
ATSF:11

Note the much higher % of SP box cars compared to Pennsy and NYC. Both Pennsy and NYC cars should be double that of SP if the G-N theory holds. BTW, the '49 data supports this relation between SP, PY, and NYC.

"But unless the train ran several times a day, it makes a
strong case for letting the X4005 train stay in staging some days, and
perhaps fiddling the other box cars in that train. If you want to
emulate N-G, then I would simply segregate the SP cars dedicated to
this train from the rest of your fleet balance targets. So now you
need 15 SP cars for X4005, and 100 for the rest of your trains to
maintain N-G."

Which is exactly what I do. Great minds....

"To my thinking, the intent of N-G is make a model railroad visit more
like a stop along the prototype's track. If you randomly stoped along
sherman hill in your era for 3 hours (more if you run a fast clock),
would you expect to see X4005 every visit? IF yes - run it every session."

Possibly...but it wouldn't look the same.

"As for the MWR car, same concept, how may 3 hour visits to sherman
hill before you spot it? One, ten, one hundred?"

Well...each visit would for our purposes see 8 trains...about 240 box cars. If randomly distributed, in each group of 7400 box cars I would expect to see one MWR car. That would be 247 frt trains. IOW, I could expect to have to do 31 visits to expect to see one MWR car. UP, however, is moving 35 frt trains in one day, 1050 box cars, and the MWR car should appear once in each 7400 or once each 7 days [ the shortened time span from 10 to 7 is due to an increase in 1953 to 100 MWR cars from 75 ]. So, while a bum sitting beside the tracks might see an MWR car every 7 days [ and wonder what the heck it is doing there ], our illustrious frt car evaluation team, being whimps and only checking during a 3 hour time period, would expect to observe for 31 days to see what the bum saw in 7. Makes you wonder who should be in charge...

"Stats would suggest it
would be pretty infrequent."

Yep. And if you dozed off...

"Same for the Ann Arbor, D&H and other
small roads (although they would appear much more often than the MWR,
but certainly these roads would not be seen every visit)."

D&H? 2963 cars. In every group of 7400 box cars, 30 D&H cars, 185 trains, 23 visits....To fit the N-G theory I would need about 2 cars if I had a 500 box car population. In my current population....8 trains, about 100 box cars...alas...I could only have a fifth of 2 cars...perhaps everything but the trucks.

"My lessons learned from this thread are:

1) N-G should apply to mainline trunk routes where the nation's
traffic is traversing a layout."

I agree if one applies the "Close Association SP Syndrome" fudge factor.

"6) Having cars from small roads is perfectly acceptable - but they
should be fiddled in - it could be on a dice roll, or more analytic.
It seems that having an extra 30-60 box cars from smaller lines (and
some of these may be well known lines for a smaller fleet), is all
that is required to provide some sense of "randomness" to trains
entering the layout from staging."

I agree.

"I think the concept has some very positive merit. The good news is
that having 50% of your fleet from the 11 major roads is probably
pretty easy to accomplish, unless your fleet is primarily resin, in
which case I think you can do whatever you want ;-)"

"The interesting finding is that because 50% of the boxcar fleet was in
11 roads, the "fiddle" pools do not need to be huge - 30-60 cars
depending on the size of the layout and the length of the PP's memory
(don't let them collect on-layout wheel reports!) And it is quite
reasonable to run that MWR car once every few sessions. Just don't put
it in a string of D&H, B&M, D&LW, AA, and RDG box cars, or no one may
notice it!"

Yep.

Mike Brock


Tim O'Connor
 

Mike, your sample of 18 trains represents what... about
0.1% (or 1/1000) of the total freight trains passing over
Sherman Hill in 1956?

I'm sorry, but statistical analysis applies equally to
trains as to cars. Your sample is simply TOO SMALL to
have any statistical significance.

The hypothesis of 'random distribution' of foreign cars
on major main lines, subject to local variances, is not
ultimately 'proveable' by any scientific method. But it
is not inconsistent with known prototype practices of
the time, as well as a wealth of anecdotal evidence and
prototype studies and reports regarding car supply and
traffic and interchange data. There is also a wealth of
contrary data, especially of the anecdotal variety or
limited samples of conductor records.

As many have noted, as modelers with layouts, we can
create a traffic model for our operations (origins &
destinations & volumes) and simply let the (car) cards
fall where they may. Known examples of car assignments,
prototype train schedules, etc, can skew our layouts'
mix in any direction it takes us. There will NEVER BE
A SCIENTIFIC PROOF of any of this. It is POINTLESS for
us as modelers to question other modelers' preferences.

What we can do perhaps is answer specific questions
about specific prototype operations, traffic, etc at
specific places at specific times. What people choose
to do with that information is almost as random as the
car distribution model we're talking about.

I'll give you an example. I gave someone on this list a
prototypically correct kit the other day, and even went
so far as to identify EXACTLY the prototype class, and
paint scheme, car number, details, etc. That person then
built the kit and painted it INCORRECTLY because they
chose not to believe the information I had given them.
(I had also given them a correct set of hard to find
decals for the car.)

The example I think speaks volumes about our hobby!
People like Jack Burgess are indeed RARE -- someone
who truly models a prototype as faithfully as humanly
possible. The rest of us are pretty much doing what we
feel like doing, rationalizing the results, and calling
it prototype modeling. I'm not knocking it, I just think
it is what it is.

Tim O'Connor


Mike Brock wrote

Right. I could simply strongly over weight the number of SP box cars in
order to be able to generate X4005. Also, the other data shows a much
greater representation of SP box cars so it would not be a problem. The 1956
box car data [ 18 trains ] shows:

UP: 157
PRR: 48
NYC: 45
SP: 43
Milw: 22
CNW: 17
GN: 17
SR: 13
B&O:13
NP: 13
ATSF:11


Richard Hendrickson
 

On Feb 6, 2009, at 6:01 AM, devansprr wrote:
--- In STMFC@yahoogroups.com, "Mike Brock" <brockm@...> wrote:
What does this do for the MWR car? Well, nothing. The 1953 ORER
shows 100
MWR box cars. For me to have one MWR box car and match the N-G data
base, I
would need 7400 box cars.













So, given the size of your freight car fleet, you could run it maybe
once or twice a year over Sherman Hill without getting raised
eyebrows. Same is true for your Tennessee Central hopper. .But
certainly not in every operating session.



**************************************

...N-G DOES NOT apply to branch lines, or even medium sized lnes that
were not "trunking" the nation's traffic, in part because some (or
many) cars may be in captive service.






My point exactly. My remarks were directed specifically at the issue
of whether an MWR box car was even remotely plausible on Jack
Burgess' Yosemite Valley layout, to which the answer remains a
resounding NO.

For what it's worth, I have a model of an MWR box car which, when
built, I will include VERY occasionally in one of the trains on my
diorama representing the Santa Fe main line in Southern Calif. in
1947. Odd-ball cars did turn up occasionally on main line trunk
railroads, so there's nothing wrong with modeling them if you don't
overdo it. But it is very easy to overdo it, and the temptation to
overdo it seems almost irresistible to some modelers who are
fascinated by the obscure.


Richard Hendrickson


Mike Brock <brockm@...>
 

Tim O'Connor says:

"Mike, your sample of 18 trains represents what... about
0.1% (or 1/1000) of the total freight trains passing over
Sherman Hill in 1956?"

Well...lessee. The time period is about a month. If so, UP was running about 35 trains per day. Hmmm. In 30 days UP ran about 1050 trains over the HIll. I have data on 18...or about 1.7% of the actual data.

"I'm sorry, but statistical analysis applies equally to
trains as to cars. Your sample is simply TOO SMALL to
have any statistical significance."

Of course it is. But...it's all we got. Plus the '49 data and some video. Certainly the real data does not predict the consist of the next train...anymore than what the guy in Vegas will roll after his 12th "7". It DOES tell us the consist of specific trains and since we are trying to simulate those in miniature, it IS a choice of something to use as a guide.

"The hypothesis of 'random distribution' of foreign cars
on major main lines, subject to local variances, is not
ultimately 'proveable' by any scientific method."

Right again. You're doing good.

But it
is not inconsistent with known prototype practices of
the time, as well as a wealth of anecdotal evidence and
prototype studies and reports regarding car supply and
traffic and interchange data."

"There is also a wealth of
contrary data, especially of the anecdotal variety or
limited samples of conductor records."

Oooops. Now what might that be?

"As many have noted, as modelers with layouts, we can
create a traffic model for our operations (origins &
destinations & volumes) and simply let the (car) cards
fall where they may."

Car cards?

"Known examples of car assignments,
prototype train schedules, etc, can skew our layouts'
mix in any direction it takes us. There will NEVER BE
A SCIENTIFIC PROOF of any of this. It is POINTLESS for
us as modelers to question other modelers' preferences."

Yep. OTOH, it IS interesting to speculate or to promote various theories...not unlike what those in historical fields do from time to time...you know...what would have happened had if UP and SP not been broken up?

"What we can do perhaps is answer specific questions
about specific prototype operations, traffic, etc at
specific places at specific times. What people choose
to do with that information is almost as random as the
car distribution model we're talking about."

Yep.

"I'll give you an example. I gave someone on this list a
prototypically correct kit the other day, and even went
so far as to identify EXACTLY the prototype class, and
paint scheme, car number, details, etc. That person then
built the kit and painted it INCORRECTLY because they
chose not to believe the information I had given them."

Reminds me that I have numbered one of my SC&F Harrimans incorrectly. The trouble is...I can't blame it on anyone except UP for renumbering the damned things without my permission.

"The example I think speaks volumes about our hobby!
People like Jack Burgess are indeed RARE -- someone
who truly models a prototype as faithfully as humanly
possible. The rest of us are pretty much doing what we
feel like doing, rationalizing the results, and calling
it prototype modeling. I'm not knocking it, I just think
it is what it is."

The late Terry Metcalfe modeled a PFE reefer train. I thought that was kind of neat...a goal. Then along came X4005 with its 36 SP box cars of every imaginable class. Sorta hard to duplicate since many...if identified...probably aren't available. Like I say...I'm a serious model RRer but I don't take it seriously. I'll do about 12 of the SP box cars.

Mike Brock


Anthony Thompson <thompson@...>
 

Mike Brock wrote:
The late Terry Metcalfe modeled a PFE reefer train. I thought that was kind of neat...a goal. Then along came X4005 with its 36 SP box cars of every imaginable class. Sorta hard to duplicate since many...if identified...probably aren't available. Like I say...I'm a serious model RRer but I don't take it seriously. I'll do about 12 of the SP box cars.
Which classes aren't available, Mike?

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@signaturepress.com
Publishers of books on railroad history


Tim O'Connor
 

The late Terry Metcalfe modeled a PFE reefer train. I thought that was kind
of neat...a goal. Then along came X4005 with its 36 SP box cars of every
imaginable class. Sorta hard to duplicate since many...if
identified...probably aren't available. Like I say...I'm a serious model
RRer but I don't take it seriously. I'll do about 12 of the SP box cars.
Mike Brock
Mike

Actually for your era, chances are good that almost
all of the SP classes can be modeled.

Tim


Tim O'Connor
 

Tony

Some of the automobile classes are not available, like
the A-50-10. But almost everything is there, it's quite
amazing really -- SP and PFE modelers are very fortunate.

UP modelers on the other hand, have gotten the short end
of the stick. Those darn ACR sides... :-)

Tim O'

At 2/6/2009 04:24 PM Friday, you wrote:
Mike Brock wrote:
The late Terry Metcalfe modeled a PFE reefer train. I thought that was
kind of neat...a goal. Then along came X4005 with its 36 SP box cars
of every imaginable class. Sorta hard to duplicate since many...if
identified...probably aren't available. Like I say...I'm a serious
model RRer but I don't take it seriously. I'll do about 12 of the SP
box cars.
Which classes aren't available, Mike?

Tony Thompson


Anthony Thompson <thompson@...>
 

Tim O'Connor wrote:
Tony
Some of the automobile classes are not available, like the A-50-10. But almost everything is there, it's quite amazing really -- SP and PFE modelers are very fortunate.
Yes, I knew that--wondered if Mike had some in mind I didn't know about.

UP modelers on the other hand, have gotten the short end of the stick. Those darn ACR sides... :-)
Quite right.

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@signaturepress.com
Publishers of books on railroad history