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Dimensional Data - wrong assumptions


Aley, Jeff A
 

Hi Folks,

 

The dimensional data in the attached image doesn’t make sense to me.  I tried to puzzle it out using the ORER, but no luck.  Obviously I have a wrong assumption somewhere.  Here’s my thinking and you can tell me where I’ve gone wrong:

 

EX. W 10 – 5 is the Extreme Width of the car.  It’s the widest point of the car.  H. 13-1 is the Extreme Height of the car.  It’s the highest point on the car (over the running board or brakewheel).

E.W.  9-4 is the Eave Width of the car.  It’s how wide the car is at the eaves, so one will know if it’ll clear a canopy on a loading dock.  H. 14-0 is the height of the car at the eaves, again so that it can clear a canopy.

 

How can the Eave Height be 14-0, which is greater than the Extreme Height of 13-1?  Obviously I’ve misunderstood something, but what?

 

BTW, the ORER gives the “Height, To Extreme Height” as 14-8.  So what, then, is the “H 13-1” next to the EX. W??

 

I don’t think it’s a stencilling error, as I see a similar discrepancy on a UP A-50-21.

 

Thanks for your help,

 

-Jeff

 


Dave Parker
 

Jeff:

The EXW is, as you say, the extreme width of the car.  But EXH is not the highest point of the car, but rather the height at which the EXW occurs.

EW and EH are the relevant dimensions at the eaves, although there was some little twist in there having to do the with the latitudinal running boards.  It would take me a while to dig that nugget out.

BTW, the EXW and EXH stencils (for cars >12 ft at the eaves) were added to the ARA standard with an effective date of March 1, 1930.
--
Dave Parker
Swall Meadows, CA


Robert kirkham
 

Is it the width at those heights?

Rob

On Sep 5, 2020, at 11:01 AM, Aley, Jeff A <Jeff.A.Aley@...> wrote:

Hi Folks,
 
The dimensional data in the attached image doesn’t make sense to me.  I tried to puzzle it out using the ORER, but no luck.  Obviously I have a wrong assumption somewhere.  Here’s my thinking and you can tell me where I’ve gone wrong:
 
EX. W 10 – 5 is the Extreme Width of the car.  It’s the widest point of the car.  H. 13-1 is the Extreme Height of the car.  It’s the highest point on the car (over the running board or brakewheel).
E.W.  9-4 is the Eave Width of the car.  It’s how wide the car is at the eaves, so one will know if it’ll clear a canopy on a loading dock.  H. 14-0 is the height of the car at the eaves, again so that it can clear a canopy.
 
How can the Eave Height be 14-0, which is greater than the Extreme Height of 13-1?  Obviously I’ve misunderstood something, but what?
 
BTW, the ORER gives the “Height, To Extreme Height” as 14-8.  So what, then, is the “H 13-1” next to the EX. W??
 
I don’t think it’s a stencilling error, as I see a similar discrepancy on a UP A-50-21.
 
Thanks for your help,
 
-Jeff
 
<UP 183586 7-30-1950.jpg>


Dennis Storzek
 

On Sat, Sep 5, 2020 at 01:11 PM, Robert kirkham wrote:
Is it the width at those heights?
Rob has it right, the H dimension that follows the EXW dimension tells you how high up the car the extreme width is. Sometimes it's really low, like at the door latch bars on a plug door reefer. At thirteen feet up, it's likely the upper door track.

Dennis Storzek


Aley, Jeff A
 

Thanks guys, but I’m still puzzled. 

 

Now it appears that I don’t understand the ORER.  The ORER has a column labeled, “Dimensions – Outside – Height from rail – To Extreme Width”.  For this car, UP 183586, that dimension is 5’2” (which is probably a grab iron).  Am I misunderstanding this column?  I think not, because I did read the “Key Pages for Standard headings in registration pages” in the back of the ORER reprint (p786 in the NMRA 1953 ORER reprint).

 

All this arose because Jacob Damron asked about dimensional data for a custom decal set he’s making.  I looked up the car in the ORER, and gave him some numbers, but now I fear that I gave him the wrong numbers.  We wouldn’t want the decals to be wrong, now would we?

 

Thanks again for the further education.

 

Regards,

 

-Jeff

 

 

From: main@RealSTMFC.groups.io <main@RealSTMFC.groups.io> On Behalf Of Dennis Storzek
Sent: Saturday, September 05, 2020 2:06 PM
To: main@RealSTMFC.groups.io
Subject: Re: [RealSTMFC] Dimensional Data - wrong assumptions

 

On Sat, Sep 5, 2020 at 01:11 PM, Robert kirkham wrote:

Is it the width at those heights?

Rob has it right, the H dimension that follows the EXW dimension tells you how high up the car the extreme width is. Sometimes it's really low, like at the door latch bars on a plug door reefer. At thirteen feet up, it's likely the upper door track.

Dennis Storzek


Dave Parker
 

In my experience, if you look at multiple ORERs over the years, the outside dimensions are often inconsistent, especially the various heights.  I'm not really sure what changed -- conventions, hardware on the car, other?  I also have seen examples of that H at the EXW being quite low (~5 ft), but am not sure I have seen it in an actual car stencil.

Whenever possible, I follow what's in a period-appropriate photo.  Absent that, I may go with what's in an ORER if it seems to make sense.  Absent that, I fake it.  If I don't know what the correct dimension is, what are the odds that somebody else will (and notice)?
--
Dave Parker
Swall Meadows, CA


Dennis Storzek
 

I looked at the ARA lettering diagram presented in the 1931 CBC, but at that time the arrangement only included EW and EH, which are the width and height of the eaves, with a not explaining that if the latitudinal platform is as wide as the eaves, the height over the platform should be used. I then checked the 1946 CBC, which used the same drawing, with a note that it was last revised in 1936 with the EXW dimension being added, but no mention of the corresponding height. I 'm sure that the data arrangement:

EXW 00-00    H 00-00
EW   00-00    H 00-00

was in use before the war but am at loss to explain why the info in the CBC wasn't updated. We need to chech an AAR field manual from the period, bi, unfortunately, don't have one.

Dennis Storzek


Dave Parker
 

Dennis:

The car lettering diagrams in the CBCs are not always up to date. For example, the diagram accompanying the "1920 Revision" that appears in the 1922 CBC dos not show the journal repack stencil that was adopted in 1920.

The absence of the  EXW and EXH stencils in the 1931 CBC is another example.  But, these stencils were proposed (pp. 616-620) and approved (p. 1020) in the 1929 ARA Proceedings.  Effective date to be March 1, 1930. 

The CBCs were effectively trade catalogs, and should be considered a secondary source for MCB/ARA/AAR standards or rules.
--
Dave Parker
Swall Meadows, CA


Tony Thompson
 

Well said, Dave. Sometimes the EXH of a house car is only 3 feet.
Tony Thompson 


On Sep 5, 2020, at 2:06 PM, Dennis Storzek <destorzek@...> wrote:

On Sat, Sep 5, 2020 at 01:11 PM, Robert kirkham wrote:
Is it the width at those heights?
Rob has it right, the H dimension that follows the EXW dimension tells you how high up the car the extreme width is. Sometimes it's really low, like at the door latch bars on a plug door reefer. At thirteen feet up, it's likely the upper door track.

Dennis Storzek


Dennis Storzek
 

On Sat, Sep 5, 2020 at 06:35 PM, Dave Parker wrote:
The CBCs were effectively trade catalogs, and should be considered a secondary source for MCB/ARA/AAR standards or rules.
Dave, I certainly agree. I simply stated what I found to save others the trouble of looking. Now, do you have a copy of the 1929 ARA proceedings and could you quote how the EXH stencil is defined? I think that's what people are looking for, the official word, so to speak.

Dennis Storzek


Dave Parker
 

Hi Dennis.

Yes, I have the digitized copy, and folks who have figured out to gain member access to the Hathi Trust collection (a subject of some prior posts) can find it here, and download the PDF:

https://babel.hathitrust.org/cgi/pt?id=mdp.39015021053742&view=1up&seq=5

The discussion and figures are quite interesting (to me), as they tie into the ARA clearance diagrams (for running cars through tunnels) as well as the columns of dimensional data in the ORERs.  Some relevant history as well.

This snippet is the actual change to the official ARA language that was approved by mail ballot:



There were also some minor changes to the Notes in the 1927 standard lettering diagram to bring everything into alignment.  So there should be a 1930/31 revision to that drawing (absent from the 1931 CBC as we have discussed) that has the revised notes as well the the EXW and EXH stencils.

Hope this helps and best regards.
--
Dave Parker
Swall Meadows, CA


Dennis Storzek
 

On Sun, Sep 6, 2020 at 11:38 AM, Dave Parker wrote:
Dave,
Do I interpret the second point correctly that they only want the extreme width that occurs above 12 feet over the rail, and the height to it? That would make sense if they were mainly concerned with tunnel clearances, as the top corners of the car would be most likely to impinge on the tunnel lining, but this puts this dimension at variance with what is reported in the ORER, which is looking for the widest point of the whole car and the height to it. That may be where some of the confusion comes from, and also explains the comment that one doesn't see low numbers in the EWH stenciling.

Dennis Storzek


Dave Parker
 

Dennis, I think you hit the nail on the head.  I am not sure the EXW had to occur above 12 ft, but rather that it be up near the eaves somewhere.  So, a car might have been right at 12 ft to the eaves (or actually the lat running board), but the the relevant widest point could have been the upper door track at something like 11-8 high or thereabouts.  I agree this could account for a lot of the confusion we have been discussing.  It follows then that the EXH dimension for stenciling may not be knowable from the ORER if the reporting road used one of the low protrusions at ~5 ft for the EXH entry. 

I note in passing that some roads seem to have never complied with this part of the standard.  I hoard B&M house-car photos, but have never seen an EXW and EXH stencil on one.
--
Dave Parker
Swall Meadows, CA


Dennis Storzek
 

On Sun, Sep 6, 2020 at 05:59 PM, Dave Parker wrote:
I note in passing that some roads seem to have never complied with this part of the standard.  I hoard B&M house-car photos, but have never seen an EXW and EXH stencil on one.
Are you sure? Both 40' steel boxcars on this Protocraft page have them:
https://protocraft48.com/category.cfm?ItemID=919&Categoryid=20

Dennis Storzek


Dave Parker
 

Well, I knew as soon as I wrote that someone would find an exception.

My excuse is that those steel cars are from the future.  I have never seen the EXW and EXH stencils on a 36-ft car, a USRA car, or an XM-1, regardless of when the photo was taken.  Including this one:



No Idea why the B&M did not apply these stencils on so many other cars.  But I think there are other examples out there as well, certainly for individual cars well past the 1930 implementation date.  I hesitate to say this, but I don't see them on any PRR cars in my rather meager collection either.  But then I don't have anything built later than the X29s.
--
Dave Parker
Swall Meadows, CA


Dennis Storzek
 

On Sun, Sep 6, 2020 at 10:17 PM, Dave Parker wrote:
No Idea why the B&M did not apply these stencils on so many other cars.  But I think there are other examples out there as well, certainly for individual cars well past the 1930 implementation date.  I hesitate to say this, but I don't see them on any PRR cars in my rather meager collection either.  But then I don't have anything built later than the X29s.
I think the reason was that these are low cars... admittedly your B&M example is 12'-5" to the eaves, but it had also been on the road a few years when the stenciling change was implemented in 1930. The requirement that all cars higher than 12'-0" at the eaves sounds rather arbitrary, and I'm sure that the railroad mechanical officers knew it. They also knew that the intent of the rule was to get these new dimensions stenciled on the new 10'-0" IH cars then being ordered by some roads, and indeed the car builders seemed to be cooperating. Existing cars in the fleet obviously weren't bumping anything and weren't changed

There was some sort of revision in 1936, it's mentioned in the 1946 CBC without saying what was revised, but I suspect that is when the format having the extreme width and height on one line and the eave width and height on the next line was implemented, which is easy to pick out in photos because the top two lines are longer and the block of data looks ragged. There was another variation of this arrangement, much favored by the Canadian National, where the size of the lettering in these two top lines is reduced and condensed so the data block becomes rectangular again. Some photos of 1950's era B&M cars on the Fallen Flags web site show that B&M adopted this practice also in the blue car era.

Dennis Storzek


Dave Parker
 

Dennis:

A good place to see some of the variation in how the EXH and EXW stencils were applied is to leaf through Ted's FOFC volume 9.  Most of the cars there had '34 or '35 reweigh dates, so it's early days. Some cars didn't have these stencils, but many did, and the format varied.  Some of this looks to be simple exigencies due to the presence of the truss members on these SS cars.

I'm not sure what changed in 1936, but note this wording in the 1929 Proceedings:



So, it seems that the initial idea was not include the "X", but instead the two sets of width and height figures would be differentiated only by the order presented.  Again referring to FOFC 9, I can find a couple of examples of this, but it looks like many roads went ahead and used the "X" to make it unambiguous as to which was which.

This is pretty speculative, but I have yet to find anything about these stencils after the 1929 Proceedings.
--
Dave Parker
Swall Meadows, CA


Aley, Jeff A
 

Guys,

 

               Many thanks for delving into these details to find the answer to my question (and confusion)!  I am grateful to your for taking the time.

 

Regards,

 

-Jeff

 

From: main@RealSTMFC.groups.io <main@RealSTMFC.groups.io> On Behalf Of Dave Parker via groups.io
Sent: Sunday, September 06, 2020 6:00 PM
To: main@RealSTMFC.groups.io
Subject: Re: [RealSTMFC] Dimensional Data - wrong assumptions

 

Dennis, I think you hit the nail on the head.  I am not sure the EXW had to occur above 12 ft, but rather that it be up near the eaves somewhere.  So, a car might have been right at 12 ft to the eaves (or actually the lat running board), but the the relevant widest point could have been the upper door track at something like 11-8 high or thereabouts.  I agree this could account for a lot of the confusion we have been discussing.  It follows then that the EXH dimension for stenciling may not be knowable from the ORER if the reporting road used one of the low protrusions at ~5 ft for the EXH entry. 

I note in passing that some roads seem to have never complied with this part of the standard.  I hoard B&M house-car photos, but have never seen an EXW and EXH stencil on one.
--
Dave Parker
Swall Meadows, CA


Dennis Storzek
 

On Mon, Sep 7, 2020 at 10:55 AM, Dave Parker wrote:
So, it seems that the initial idea was not include the "X", but instead the two sets of width and height figures would be differentiated only by the order presented.  Again referring to FOFC 9, I can find a couple of examples of this, but it looks like many roads went ahead and used the "X" to make it unambiguous as to which was which.
Dave,
As I mentioned before, the 1946 CBC presents the same drawing as was presented in the 1922 CBC, but adds the following note in text below the drawing with its included notes:

"Note 1 - 1936 Revision Provides for EXW Stenciling and Notes are Amplified."

The ARA itself may have realized two sets of identical dimensions showing different numbers was confusing and made the change itself in the first couple of years.

This discussion has been informative. Thanks for taking the time to clip parts out of the ARA proceedings and post them.

Dennis Storzek 


Dave Parker
 

Dennis:

That seems quite reasonable.  I have the ARA Proceedings from 1930-32, and I don't THINK this issue is addressed in them.  Someday I hope to catch up to a few more years worth, and might remember to check on the EXW and EXH stencils at that time.  ;-)
--
Dave Parker
Swall Meadows, CA