Saturday, 27 June 2020

Adding Weight to rolling stock

Correct weight??

In order to achieve a good running layout, I think it is wise to bring all the rolling stock up to a standard in weight. I chose to fairly closely follow the NMRA weight standard for rolling stock.
I have spent the last few days weighing each car on the layout. At this point probably 300 cars in total.

I found most of the newer Microtrains 50ft cars and some 40ft cars are on spec, but all the Atlas cars are under as is older rolling stock from Minitrix etc.

I have had a tub of lead shot (from 12 gauge shot gun cartridges) in my drawer for many years and decided to find the best way to add weight. In the majority of cases 2 x Zinc plated 5/16th hexagon nuts super glued to the floor of cover hoppers, coal cars and box cars did the trick. In some cases 2 x 3/8th nuts for the lighter cars. For the gons I either added a load that has some weight about it, or added the lead shot to the underside of the car and super glued it in place. For tank cars, I simply loaded them with lead shot up to the right weight and reassembled them. For the Atlas 90t coal hoppers with coal load, the load has 2 internal posts so I just placed the nut over the post to stop it float around in the car and placed the load back in place.

Here are a few pictures showing progress.

Here is the web page I used to do the calculation for me

As I have 2% grades on the layout and most newer loco's don't pull well, I have adopted the idea of a car to motive power ratio. I had read about this somewhere on the web.
The idea is that to add the right number of loco's to the train you count 2 cars per traction motor of the loco. As most D&H loco's are 4 axle then this is basically 8 cars per loco and my trains are up to 20 cars long and longer in some cases. For a 6 axle loco, like a C-628, or a U30C or a SD45, the ratio is 12 cars per axle.
This works out well as a lot of the early to mid 70's 4 axle diesels are only 2000hp to 2400hp and some only 1800hp. As I have a number of loco's and like big lash up's most trains have 3 loco's on the point.

If a train is made up of 40ft cars then it will be lighter than a train of 50ft cars or 90t hoppers.. So the appropriate motive power needs to be on the train. If the chosen loco's cant get the train up the grade I will just add another loco or do what the D&H did and use a set of helpers on the back end of the train.

Now for some testing to make sure I have not gone overboard. Most weights (nuts) are removable.


1 comment:

  1. I really like this weight to loco ratio. The real stuff has to do it so why not us little guys. That is one of the outcomes of the terrible accident in the USA many years ago. Not enough locos to control the train as it came down grade and it had a runaway causing huge damage and loss of life.