Many of you know about this and use this type of car already. This is a reminder for those that haven't tried it, and for the new modelers who may not have heard of or seen such a thing yet.
I recently built a pair (you've got to have 2, in my opinion) of track cleaning cars. I was working on some cheap Bachmann gondolas, converting them into low-sided gons, and since I had to remove the flat weights anyway they seemed like the perfect cars to make into track cleaners. In case you've never seen a masonite track cleaner, it's just a pad of masonite with a couple nails glued to the smooth side. The rough side runs on the rails and scrubs away dirt and oxidation, and the nails fit into holes drilled into a car floor.
Why did removing the weight help? Simple - because I didn't have to drill through the weights. I could have, of course, but why do more work that you have to? I hate drilling through steel like that, since I don't have a drill press.
To make the cleaning pad, I cut some scraps of masonite, 1 5/8" x 2 1/2", and cut a little bevel on the narrow ends, on the rough side. A table saw made quick work of that. I then grabbed a scrap block of wood and, selecting a drill bit a size larger than the 16d nails I would be using, drilled two holes as perfectly vertical and as close to 2" apart as possible. The 2" part is not critical, but it does need to be the same as the spacing of the holes in your car floor. I loaded two nails into the holes I'd just drilled, then clamped the block to the fence on my table saw (a convenient place to work), slipped a piece of masonite underneath, and glued the heads down using super glue.
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After removing the pad from the block, it worked very well, with one minor flaw. 16d nails are a good bit longer than the vertical clearance on an HO layout, meaning they would not fit through tunnels or under bridges. Oops. I slipped the nails back into my jig, put a scrap of wood under the pad to leave anything over 2" of the nails sticking out the top, and used a cutoff wheel to remove the ends of the nails. With that, the thing worked perfectly. Here is one of the finished cars, using 4 12" nuts as weight:
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The pad simply floats, with no weight other than that of the masonite and nails. The holes in the car floor are a little oversize, to keep it from binding.
It is impressive how well this track cleaner works! I can put an engine on the track and barely convince it to move, but run the car in front of the engine and it will work almost instantly (as soon as the engine hits the cleaned part, of course). It won't clean paint or other heavy grunge (leave that for the bright-boy), but it will do wonders on dust and oxidation. I have heard that some people run a couple of these cars before every operating session, and some run them in every operating session, as part of some train. Look at what the pad looks like after just a couple trips around my small layout:
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Remember I said you need two of these cars? The best way I have found to run them is in a simple track cleaning train - a reliable and powerful locomotive with a cleaning car coupled to each end. That way, you can go into any piece of track from either direction, and the engine is always traveling on freshly cleaned rails.
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