Large Scale Central

Am I the only one?

Prototypes
#1

While on a delivery last week, I got stopped at the entry to PP&Ls freight yard as their 100 car coal drag pulled in. Now I’ve gazed at a few trains in my day, but I was looking at details. PP&L has two fleets of hoppers for their needs. The oldest are 100 ton three bays, and the newer are 100 ton aluminum ‘bathtub’ hoppers. The three bays are numbered from,at least, 99 to around2600 and the newer cars start from there. Now the reason for this post is while watching this drag I noted that the ‘Lt. Wt.’ and the ‘Ld. Lmt.’ were differant on the cars. I had always been under the assumption that a group of the same cars, built at the same time, by(more than likely) the same builder, would be the same.WRONG. Pay attention to the following pics The first two are the full cars

Now close up shots

Now this was just a small sampling,and though I didn’t take any pics of the newer cars the same differances were noted. Also, the reason I noted this is, I’m getting ready to start lettering my equipment ,and I wanted to know what info is needed for the cars.

#2

What’s a couple of thousand pounds among friends?

#3

Tell me If I am wrong, but Don’t all those cars total weight add up to 263,000???

#4

I don’t have an answer about them cars but if make another delivery, take me with you so I can fish their warm water discharge like I used to before 9/11… There’s freakin monsters in them spillways!!

#5

Load Limit 199,700

  • Light Weighter 63,300
    = Gross weight 263,000

Gross weight is the maximum weight for the trucks and bearings and car structure.
Light weight is the empty “tare” weight of the car.
This then gives you the maximum weight of the load you can put in the car.

Does this help?

Even when cars all built at the same time, there will be variance in the weight. Cars periodically have to be re-weighted due to wear and tear, major repairs and things like that that can change to cars empty weight.

#6

That’s what I was thinking Steve, but since I didn’t know for sure I didn’t answer. I figured it was like RV’s where every one of the same model that’s built has a different scale weight, but the frame and axles have a fixed capacity. Like the cars, the carrying capacity is the difference between the two and will vary from one unit to the next.

Weight differences on two new RV’s of the same model can be caused by differing hardware, scrap left behind in enclosed places by the builder, different plumbing fixtures, etc. On a new hopper just the difference in rivet count could make a hundred or two pounds difference.

#7

Thanks all, I didn’t do the addition Andy.
And Steve W. thanks for the added Gross weight figure.
I see the #s on models and they are always the same. Not a big deal for me just curiosity, but for the rivet counter a piece of info that may make a differance.

#8

The light weight (empty or tare weight) of the car could change each time the car was shopped. Turning down the wheels or replacing them, new brake shoes, etc. all make a difference in the weight. That’s why that number can vary between two seemingly identical cars. You’ll sometimes see references to when and where the car was weighed written on the car, too.

The “top” number I’ve seen either be the total capacity (Gross weight) or the load limit. I don’t know what the rules are governing which is used. The EBT always used gross weight (“capacity”). It would seem odd to me to use load limit as a number unless you can weigh the materials being loaded into the car prior to it being loaded, such as you could do on a box car, but then if you’ve got a string of identical hopper cars, presumably you know what the capacity is for all of them anyway.

Later,

K

#9
Steve Featherkile said:
What's a couple of thousand pounds among friends?
Very important Steve, especially if they are GBP (£). It could be spent quite happily at a train show. lol

An intriguing post Kevin: like many large scalers I have a keen interest in the 1:1 railroads of the USA. Living this side of the ‘pond’ means that any good photographic material puts further information my way and is usually not the kind I read in magazines.

The point Dave makes, about individual cars data, brought a smile to my face.

#10

Steve - Gross weight is the weight at the point where the wheels meet the rails. The tare weight is the weight of the empty car. There is no means for the scales to deduct the weight of the trucks and wheels from the measured weight.

I do it all the time when I go to the land fill with a large truck load of yard debris.

Bob C.

#11

Kevin,

To answer your question on weight while loading, I used to work for a company that made belt scales to read and calculate the tonnage of coal going across the scale during operation. They can actually tell within a couple of hundred pounds on the capacity of the whole care load. If yo are interested, check out www.jblco.com - that is where I worked.

Bob C.

#12

There can also be weight differences even amongst new rolling stock. During WWII for instance material shortages sometimes resulted in substitutions during construction that could vary the weights of the first cars from the later cars within the same order series. Too, a group of cars with identical specifications built by two different manufacturers would seldom have the same tare weights.

#13

As to the 263,000 pounds, that used to be the max car loading on US class 1 roads. Since then, the American roads have agreed to a general upping to 286,000 or 143tons. The shortlines around the US haven’t yet finished upgrading to the new weight limits and the roads are already talking upping the limits to 300,000lb limits.

The barber S2 roller-bearing trucks are still good for this as each one is supposedly structurally designed to carry 150tons each.