A useful tool to have in your arsenal of model railroad train supplies is a trammel. Essentially, a trammel is a large compass that will help you accurately draft curves before placing the sub-roadbed and laying flextrack. Building your very own trammel is cheap, easy, and requires few materials. This tool will assist you in planning your track layouts by providing a consistent arc every time.
Constructing a Trammel and Putting it to Use
Laying curved model railway track can be tricky. It takes a bit of planning and sketching before placing the sub-roadbed and laying the track. During this process, you can use a trammel to draw the curves. This method doesn’t require any estimating or guessing. With the trammel you will draft the exact radius curve needed for your track. In this particular video, NMRA Master Model Railroader Gerry Leone demonstrates how to create a homemade trammel to help you create 30-degree radius curves. Tracks are sold in various radii, but the trammel can adjust to any size needed.
Gerry demonstrates not only how to make a trammel, but also how to properly use it. Modeling trains often means working in tight areas around the layout. Gerry developed a trick for using the trammel when you lack a location to plant the focal point of the tool. It serves as a great technique for working in corner areas that are not obstructed.
Making a trammel will prove to be useful when creating curved model railway track. It is simple to create one just like Gerry’s. Follow along for the steps of creating and using the tool. With these tips and tricks, you will create a perfect arc every time.
I used something similar using 2 pieces of thin wood. the outer 2 were clamped to the benchwork and the center one ( a yardstick) used for the radius. I also drew my curves 1/4 to 1/2 inch inside the tangent track to allow for easement transition.
Trammel should be parallel to the plane of the roadbed to get the true radius desired. In the video, the trammel appears to be angled downward from the pivot point and not parallel to the roadbed.