The reason I seen sparking. The wheel brushes were not making contact with the wheels.
Electricity would flow through the wheels and the rail wipers would not spark.
I am mounting brushes on all wheels and interconnecting the driving trucks.
The best thing is if you can get good enough pickup, is to do without the wipers entirely.
But if you saw a lot of sparking, then they were handling (or trying to handle) a lot of current.
I remove all of mine from my USAT stuff, they have similar problems with the springs, and the wiper hanging up.
Regards, Greg
Visit my site: http://www.elmassian.com - lots of tips on locos, rolling stock and more.
Click here for Greg's web site
I been having a major problem with MTH's rail wipers. I been removing them and adding Aristo's wheel brushes.
I started to work on my MTH Challenger. I noticed a lot of sparking from the rail wipers. I found wheel brushes on two sets of drivers on both trucks. When I checked the brushes with a"OHM" meter. I seen the brushes were not contacting the wheels.
I removed the brush holder and brushes. I found the brushes were to tight of fit in the brush mounts. I had to reduce the diameter of the carbon brush. I also had to shim the spring. The brush holder is made so I could not remove the spring. I wanted to replace the spring with one from a ball point pen.
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