Maine Central, Lamoille Valley

Maine Central, Lamoille Valley
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Wednesday, January 14, 2015

Ways to Weigh

I have continued my rolling stock weighting program over the last few months. It has worked in conjunction with getting ready for operating sessions. I have been staging the railroad and getting the proper cars in the right places, and checking and updating waybills as necessary. In doing that I also check the cars for proper coupler movement and height, proper wheel gauge and tightness of truck screws to prevent wobbling. Along with this I also add the additional weight I am seeking.

It is a fairly easy task and lends itself well to the "try to do one thing everyday on the layout" method of getting (model railroad) things done. I can easily spend just 30 minutes getting 3 or 4 cars "upgraded". Over time that has added up and I now have well over 100 cars ready for "heavy" operations.

Some cars are easier to address the weight issue than others. Boxcars with removable underframes are the easiest. Ones with removable roofs may take a little extra work depending on whether they were glued or not. Covered hoppers also vary depending on the design. Kato ones were easy as the whole shell pops off the underframe, while older E&B Valley ones are a little tougher having to pry off a glued on roof.

Tank cars have been another matter entirely. In Mike Confalone's e-books he mentioned and showed a picture of an Atlas tank car where he simply drilled a hole in the bottom and filled the car with sand. Besides being extremely cost effective, the amount of sand in a Kaolin tank car puts it at 7.5 ounces, right where I want to be for appx. 40 foot cars. As there is no real easy way to disassemble the cars to add weight, this seems to be the best method.

Doing the drilling takes a little care. I started with smaller drill bits and worked up to a larger one, 1/2". Starting with a larger one can easily cause the drill bit to grab the plastic and start spinning the whole car, sending parts all over. Yeah, that happened once, and I took great care not to do it again!

Once I have a hole about 1/2" wide I use a paper funnel and slowly worked sand into the car. It takes  little longer than I would like and I needed to keep shaking the car to get the sand to work its way around the car. There is a weight that you will see that runs through the car, and the sand needs to work its way past the small openings along the edges to get to the top half of the car.

I fill it up until it weighs 7.5 ounces. There is not much more room to add sand at that point anyway, so weighing it makes it easy to know when I can stop. I plug the hole with some acrylic caulk and when it is dry hit it with a grimy black marker to make it nearly invisible.

This Atlas Kaolin tank car is filled with sand, weighing int 7 ounces. The white dot is the plug, which will be painted black. The paper funned and a dish to catch spills is on the right.

I found with Walthers tank cars that you can pry off one of the end caps using a finger nail. With practice, I was able to keep it attached to the handrail, add self stick weights and pop it back on.

The Walthers tank car can be opened up at the end allowing a quick and easy install of self stick wheel weights.
I still have a number of cars to do, and some will require some thought. Gondolas with a load are not too difficult. I have been able to add flat weights from older box cars underneath loads by Motrak models. Open hoppers I have decided to just add the self stick weights to the inside slopes even though they will be visible when a coal or wood chip load is not present. My layout height makes it difficult to see inside these cars most of the time. It is a compromise, but well with it for the better operating reliability.

A woodchip hopper with additional weight. I'll go back and weather the inside to help disguise the weights when the car runs without a load.

In operating tests, I have really liked the extra weight. The cars do not wobble, couple easily and stay on the tracks well. One or two cars that have derailed have identified either a truck issue or in one case a track work deficiency. On the Maine Central route there is not much in the way of grades. The LVRC does have a steep grade, but two RS3s are easily handling 10 freight cars (which represent about 5 pounds of trains). Ten cars should be the max I operate on this line, much like the prototype.


George Dutka said...

Hi Mike:
The tank car full of sand is a really good idea...will have to try that one...thanks for sharing...George Dutka

Shannon Crabtree said...

I definitely want to do this also. Glad your giving some inspiration! Great site and keep the excellent updates.

Cam said...

Mike you could paint the weights in the hoppers and they will be less noticeable.

Matthieu Lachance said...

For Atlas kaolin tank cars, I removed the top tank access hatch and poured sand through it. The hole is small, so it took some 30 to 45 minutes to fill each car. Not very time efficient but no scar on the car.

Colin 't Hart said...


Can you tell us how much weight you install in different length cars? I seem to recall your namesake Mike (Confalone) writing that he goes for something like 11-12oz in all cars regardless of length.

I also want to start superweighting my cars, but I'm having trouble deciding whether to go for "superheavyweight" or something a bit in between.

Does it also matter much if you have a few lighter cars in a consist? I'm worried that if I bring some cars up to 12oz that a tank car which can only be brought up to say 6oz using sand will cause problems!



Mike McNamara said...


It varies a little, but most 50' cars are 8.0 to 8.4 ounces. Most 40' boxcars are 7.5. Some covered hoppers are around 6.8. So I am not super weighting these like Mike C. does, but so far I am happy with the results. In some cases adding more weight will really present an issue. I was able to get 50' gondolas up to 8.0 by adding a flat weight under the load of scrap for example. But hoppers would be tough to get more weight because it starts to ride higher as you add more, and that might be an issue. And of course the Kaolin tank cars are full and come out to 7.0 to 7.5. It could be Mike C. has more varying weights, not sure.

I do know that the few light cars I have left operate OK so far, but I do not plan to leave them unweighted. I only have a small amount left to do, most of which are tougher because of how the model was constructed. Sometimes tough to do with out causing a little damage.

The other thing I have found is that when I pick up a regular weight car, even if it is at the NMRA 4.5 for example, it feels so light I cannot believe it even stays on the track! Interesting how quickly you get used to the extra weight!


Colin 't Hart said...

Thanks Mike! I hadn't thought that adding even more weights might raise the center of gravity, so that's indeed a good argument to go for the middle ground like you've done. I'll be following your guidelines then.