Topics

Tank Car Reweigh and Other Markings


Ray Carson
 

Hello everyone,

With the release of Tangent's new run of 8000 gallon 1917-design tankers, I was interested in something that got me confused months before.

So I was reading on Tony Thompson's blog regarding an SP tank car he was building in 2014 (https://modelingthesp.blogspot.com/2014/04/modeling-sp-gasoline-tank-car.html) and in one part he says:

On the tank at this point, there is no reweigh date. Tank car cargoes were billed by gallonage, not by weight, so the car’s light weight was of no importance (unlike all other types of freight cars). Prototype photos commonly show tank cars having weigh dates a decade, or even multiple decades, prior to the photo date. But when cars were repaired, they were ordinarily reweighed, and SP tank cars often do show that change.

Okay, that makes sense. However I've seen photos of tank cars with their dates reflecting when the photo was taken in service. I even recall seeing photos of tank car models with reweigh dates for some modelers modeling a year. Was this something overlooked or am I getting myself confused with tank cars?

So in the end, would a Tangent 1936+ scheme tank car fit my 1939 year without making any decal changes? How about older tank cars that are 5+ years older? I'm overall used to the concept of freight cars being reweighed every 1-2 years depending on whether wood or steel bodied and tank cars being an exception confuses me a bit.

Thanks, Ray


Bruce Smith
 

Ray,

I'm not sure why you are confused. Tony's comments are clear. Tank cars are not box cars. They were not required to be reweighed on a regular interval. Their cargos were not billed based on weight, but on volume. This a shipper has no need for an accurate light weight of the tank car, since the car will not be weighed and the weight of the cargo will not be calculated from the total weight minus the light weight. Thus, just as Tony says, there are plenty of examples of tank cars with reweigh dates a decade or more old.  And yes, they can also have more current dates if they have undergone some kind of service, again, just like Tony sez...

So to answer your question, the relevance of an older scheme depends on several issues, but generally not reweigh. Older lease schemes can be inappropriate due to the lease having ended. Likewise if an owner has changed paint schemes in the intervening years, the car may have been repainted into the newer scheme. 

Regards,
Bruce Smith
Auburn, AL


From: main@RealSTMFC.groups.io <main@RealSTMFC.groups.io> on behalf of Ray Carson via groups.io <PrewarUPModeler@...>
Sent: Sunday, October 4, 2020 8:58 PM
To: main@RealSTMFC.groups.io <main@RealSTMFC.groups.io>
Subject: [RealSTMFC] Tank Car Reweigh and Other Markings
 

Hello everyone,

With the release of Tangent's new run of 8000 gallon 1917-design tankers, I was interested in something that got me confused months before.

So I was reading on Tony Thompson's blog regarding an SP tank car he was building in 2014 (https://modelingthesp.blogspot.com/2014/04/modeling-sp-gasoline-tank-car.html) and in one part he says:

On the tank at this point, there is no reweigh date. Tank car cargoes were billed by gallonage, not by weight, so the car’s light weight was of no importance (unlike all other types of freight cars). Prototype photos commonly show tank cars having weigh dates a decade, or even multiple decades, prior to the photo date. But when cars were repaired, they were ordinarily reweighed, and SP tank cars often do show that change.

Okay, that makes sense. However I've seen photos of tank cars with their dates reflecting when the photo was taken in service. I even recall seeing photos of tank car models with reweigh dates for some modelers modeling a year. Was this something overlooked or am I getting myself confused with tank cars?

So in the end, would a Tangent 1936+ scheme tank car fit my 1939 year without making any decal changes? How about older tank cars that are 5+ years older? I'm overall used to the concept of freight cars being reweighed every 1-2 years depending on whether wood or steel bodied and tank cars being an exception confuses me a bit.

Thanks, Ray


Ray Carson
 

I was mainly confused due to seeing prototype photos with a "reweigh" date taken before photos (don't have any example photos, sorry) and I kept assuming tankers were treated the same as other freight cars. However I guess I was overthinking a bit on Tony's post due to me being used to the concept of freight cars reweighs as I continue to learn more about freight car assignments.

-Ray


Steve Summers
 

I’ll jump into this and hopefully not add to any confusion but there is another reason for not listing the car weight on tank cars back then.  Only the largest manufacturers or customers had a scale to weigh a tank car. 

Even today due to the high cost to purchase a scale with the weight capacity needed for heavy rail cars, there are only a few customers with scales.  In fact, several manufacturers still do not have scales today, hence the use of volume (gallons) which can be measured by a meter like at a gas pump.


On Oct 4, 2020, at 10:14 PM, Ray Carson via groups.io <PrewarUPModeler@...> wrote:



I was mainly confused due to seeing prototype photos with a "reweigh" date taken before photos (don't have any example photos, sorry) and I kept assuming tankers were treated the same as other freight cars. However I guess I was overthinking a bit on Tony's post due to me being used to the concept of freight cars reweighs as I continue to learn more about freight car assignments.

-Ray


Dave Parker
 

On Sun, Oct 4, 2020 at 06:58 PM, Ray Carson wrote:
So in the end, would a Tangent 1936+ scheme tank car fit my 1939 year without making any decal changes? How about older tank cars that are 5+ years older?
Strictly speaking no.  Despite the absence of periodic reweighing, tank cars would still have had stencils redone periodically,  Specifically:

1.  Regular brake service.  Every 12 months starting back in 1901, increased to 15 months in 1933 (I believe).  This was for K brakes.  The interval was longer for ABs.  Tony has a blog piece on this.

2.  Regular journal box repacking.  Every 12 months starting in 1920; I think this also increased in the mid-1930s as there was some movement towards standardizing intervals.  I should know how/when it changed, but can't put my hands on it right now.

3.  Tank cars required periodic testing of both valves and tanks.  The block of lettering at the right end of the car-sides had to be redone or touched up to reflect the new testing dates.  From 1930 forward, the interval was after 10 years since construction, and every five thereafter.  In the 1920s, the intervals were different for valves and tank, and varied some with car class.

All of these stencils are small and generally difficult to read without magnification (in HO).   But many of us have cameras capable of capturing these <2" stencils, and pad-printing makes them quite sharp on many RTRs.

If one is really fastidious about having every stenciled date correct for the chosen model year, this is unlikely to be easily achieved with many/most tank-car models.  I suspect most folks compromise. 

PS:  Brake stencils are often more obvious on tank cars because the reservoir is often easier to see.  Conversely, the repack stencils can be harder to see on cars without stub-sills, as they were generally applied to the center sill.

Hope this helps.
--
Dave Parker
Swall Meadows, CA


Bruce Smith
 

Steve,

Um, most shippers did not have scales, so this is nothing special or specific to tank cars. It also does not present any problem. Shippers or consignees had cars weighed by the railroad. Tank cars would be no different, if billing was by weight (which it was not). 

Regards,
Bruce Smith
Auburn, AL


From: main@RealSTMFC.groups.io <main@RealSTMFC.groups.io> on behalf of Steve Summers via groups.io <summers1218@...>
Sent: Sunday, October 4, 2020 10:54 PM
To: main@realstmfc.groups.io <main@realstmfc.groups.io>
Subject: Re: [RealSTMFC] Tank Car Reweigh and Other Markings
 
I’ll jump into this and hopefully not add to any confusion but there is another reason for not listing the car weight on tank cars back then.  Only the largest manufacturers or customers had a scale to weigh a tank car. 

Even today due to the high cost to purchase a scale with the weight capacity needed for heavy rail cars, there are only a few customers with scales.  In fact, several manufacturers still do not have scales today, hence the use of volume (gallons) which can be measured by a meter like at a gas pump.


On Oct 4, 2020, at 10:14 PM, Ray Carson via groups.io <PrewarUPModeler@...> wrote:



I was mainly confused due to seeing prototype photos with a "reweigh" date taken before photos (don't have any example photos, sorry) and I kept assuming tankers were treated the same as other freight cars. However I guess I was overthinking a bit on Tony's post due to me being used to the concept of freight cars reweighs as I continue to learn more about freight car assignments.

-Ray