Sunday, October 25, 2015

Adding Weight to an Intermountain 60ft Flatcar

About 8 years ago, I acquired on a whim an undecorated Intermountain 60' flat car at a the local hobby shop. The car looked good and I decided to paint it in a hypothetic modern QRL&PCo paint scheme. Unfortunately, the car quickly was retired from operation due to poor tracking.


In fact, Intermountain 60' flatcar is notoriously known for its feather-like weight. The car is very nice, but weights no more than 1.1 oz...

Many ways were deviced by modelers to enhance the car's running. The easiest way is to add loads onto the car. Makes for an attractive solution but I'm not too eager to have permanently fixed loads on a car supposed to simulate real operation. For a switching layout, having the opportunity to run the car empty is crucial.

Thus, the other way is  to simply add weight below the wood deck. Filling the empty space under with lead shots is probably the most efficient way, unfortunately, I don't have accept to such product. I thought I could use sand glued with diluted white glue in the same manner as ballast. The idea would work with most flat cars. However, the Intermountain deck isn't 100% sealed and I feared white glue would find it's way on the deck and ruin the model.

The only remaining option was to use lead wheel weights. No particularly the easiest way out there, but feasible. To do so, I removed some internal bracings and details to make more room. I was careful to keep all the details that could be seen from the side. Lead weights required some trimming to fit the space.

After this invisible surgery, the car now weights a honest 3.9 oz. compared to the initial anemic 1.1 oz. For such a car, NMRA would recommend 5 oz., but there's a limit to what you can do. If I had other lead supplies, I could have stuffed about 1 more ounce under the car.

Now, the fun start as this car will be repainted as a CN car to fit our fleet.


  1. You solve a very tricky problem. I originally came to your site because of your great work on Tichy ore cars. The weight issue is dogging me on these cars (when empty).

    My (incomplete) solution: I bought a 25 lb bag of #12 lead shot. It consists of tiny balls of lead that can be poured into almost any crevice. I also bought a digital cooking scale. I put the cars on the scale and pour in lead shot in the hopper to suit. It makes it incredibly easy to get the weight just right.
    The problem is with the empties. I have to figure out how to spot the lead around the frame so that it doesn't show. Ideas?

    1. Thanks!

      I think the lead shot is the best solution. It would have made adding weight to the Intermountain car a walk in the park.

      The Tichy ore cars are really tricky. Would you believe me if I told you the blog statistics are clear: most people coming here have the same problem you have!

      I think part of the solution is using all metal trucks (like Kadee) in combination with additional weight. Unfortunately, there's no way to visually conceal the weight. There's two solutions, all using lead shot. First, fill the frame open areas over the trucks. Not very nice, but could do the job to some extent. Not easy to do since the glue could run out and ruin the model. I'd paint the lead shot/glue mix black to make sure the original structural members stand out.

      The other option is to fill the hopper bay up to the frame. I suspect it could hold about 1/2 oz. Also, when you turn the car upside down, there's some space between the bay and the frame. Depending the size of the lead shot, it could be filled with weight without problem and wouldn't be visible during normal operation. There's some other empty spaces under the frame that could be filled with lead shot. I'd take any opportunities to add weight.

      Taking in account metal trucks and lead shots, I wouldn't be surprised the car total weight could reach NMRA recommended practices. Adding weight inside the hopper bay could be the last resort if filling the underframe proves to be insufficient. The visual impact would be at least minimal depending the level of realism your want to achieve. Unfortunately, these cars should have a metal underframe.

      If your experiments works well, let me know and I'll post a blog entry. That should be helpful to many people!

      Best regards!