Adding weight to some of our models can be challenging. I’m working on a couple of HO scale gondola kits and both of them need additional weight. Adding weight with a load is one avenue but I want these models to be run when empty, too. Time to review some options.
The National Model Railroad Association (NMRA) established weight recommended practices (RP) several decades ago and were updated in 1990. You can download a PDF of these recommendations through the NMRA site.
For HO scale, the recommendations start with an ounce for a car, then add a half ounce for each inch of the model. A 40-foot box car is about six inches long. Following the NMRA recommendations, the car should weigh about four ounces. Some modelers like to overweight their models and some keep the weight shy of the recommendations.
I target my freight cars to weigh about 75% of the NMRA recommended practices. That 40-foot box car would weigh three ounces for my layout. I am using trucks and wheelsets that roll better than most of the equipment used when the NMRA RP was established, and when it was updated. I also use smaller steam locos and want them to pull or push an appropriate number of freight cars. Set your own standards and practices that reflect what you want from your layout.
Open top cars
Adding weight to gondola and flat car resin kits can be a challenge. With the current two models on my workbench, some underframe details are sacrificed to add weight. When weighing the models during construction, make sure you include all the final parts and trucks for an accurate weight.
I cut sheet lead to size for these models. Please use caution when working with lead. After handling lead, wash your hands and tools. Do not touch your eyes, face, or mouth after handling lead. Lead can be toxic if you are exposed to it at length.
The Westerfield Models Pennsylvania Railroad GRa gondola, has fishbelly side sills that obscure viewing underframe details. I cut slabs of the lead sheet to fit onto the underframe and on each side of the cross members. I created a paper template to use for cutting the lead. This reduces the need to trim pieces to fit. The extra weight brought this model to three ounces.
The other model is an ancient Funaro & Camerlengo B&O O-15 gondola kit. It has straight side sills, so lead pieces can’t be stacked like on the previous gondola kit. I cut lead to fit between the two fishbelly center sills and to fit between the floor stringers.
Once these lead parts fit into place, I used Barge contact cement to glue them into place. I applied the cement onto the parts and the weight locations on the model using a microbrush. After 15 to 20 minutes, the parts were set into place. For the center sill weights, I glued those together as one unit before installing them in the center sill.
The model weighs in at two ounces now. It is about an ounce shy of what I want. I’m tempted to install a thin sheet of metal between the underframe and floor castings. The shallow interior depth would take a hit with the extra thickness. I’m still mulling over this approach.
On a previous gondola kit build, I used Liquid Gravity by Deluxe Materials. These are very small beads that can be poured into place and secured using cyanoacrylate (CA) glue. This model has deeper areas between the stringers, which accommodates more of the material to weigh the car..
Even after adding the Liquid Gravity to several areas on the underframe, this Nickel Plate Road gondola remained underweight. I added a slab of 26 gauge sheet metal under the floor, as seen in the above photo. I’m considering adding a similar piece of the sheet metal for the B&O gondola noted earlier.
These are just a few ideas to install additional weight on a light freight car kit. A load can easily disguise the extra weight but I still want the freight car to run well without a load. Each model will have a challenge. Sometimes you can use an old technique, try something new, or use a combination to push the project towards the finish line.
Thank you for visiting my blog. You can share a comment in the section below. Follow the instructions so your comment can be posted. All comments are reviewed and approved before they appear. Please share the blog link with other model railroaders. To subscribe to this blog, add your email address to the function at the bottom of the right column on the main page.