This item was originally put together to assist in track ballasting. With a simple level laid across the track I could never remember which side the ballast needed to go under till I lifted the level to bring the bubble back to center. This unit worked so well I can also spot other track problems and can actually push it around and watch the level to see how level or unleveled it is and get an indication of the grade.
Construction
I took a flat car kit made by HLW. I found a two way level at a RV store that was designed to fit on the trailer tongue. I added metal wheels to the flatcar for good tracking weight. I left the poles on the car to move it around easily. The level I purchased had levelers on it so it could be set to take up any inconsistencies in the flat car and wheel combination. I added some labels to show which was the high side. I figured if I knew this the other would be the low side.
When I was testing it I actually found a small ding in the track that had been unnoticed till this time. Some random wheel problems may have been caused by this ding.
Photo below is a close-up of the top of the car.
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