Hi All,
Recently got in the NJT comet cars, thought I'd share a bit of a warning to prevent possible damage and a potential fire hazard. It looks like theres a short in the truck of the comet cars causing the spring/pickup to go super critical:
This so far has happened to every NJT comet car I've received. The solution is using liquid electrical tape, or heatshrink to isolate the top of that piston to prevent the short 
One of the insulators melted before I was able to do that
because the spring is effectively providing the resistance, it doesn't pop the breaker either. I'm unsure why atlas hasn't done a recall on these yet but please check your cars to make sure this isn't occurring!
