Atlas switch track issue

First use a multimeter to check if you have AC voltage between each of the 3 center rail segments and the outside rail.  Second, measure the distance between the two center pickup rollers on each engine.  Compare that distance with the gap between separate center rail segments where the diverging rails cross. Make sure you are measuring the metal, not plastic parts of the center rail. If the gap is equal or larger than the pickup roller separation, you will lose power.  In that case one option for the steam engine is to add a roller to the tender and tether it to the other rollers, or add a tether to an existing tender roller if the tender has IR (no tether).  Adding a third roller to a diesel or moving an existing one are options. If you move it, measure to make sure you are not creating the same problem on another turnout.

Bob

Daviddp posted:

I have a MTH Dash 9 Diesel engine and a MTH Big Boy Challenger Steam Engine whenever they go over one of the Atlas switch track they stop.  All my other smaller engines have no problem passing the switch track.  There is current going to the track.  Any thoughts would be appreciated.  dep

My dash 9's (railking) also mirrored your symptons over an atlas 7.5 but only at scale 3mph and under. I thought roller mods would provide the cure..they did not. RK six axle engines only have 2 wheels that are ground effective to the outside rails..plastic blind driver and traction axle do not provide ground path. I am in the process of changing the traction axles to solid non traction wheels. This problem doesn't exist with my premier 6 axle units as they have solid wheel sets front and rear at each truck.

willygee posted:

Daviddp posted:

I have a MTH Dash 9 Diesel engine and a MTH Big Boy Challenger Steam Engine whenever they go over one of the Atlas switch track they stop.  All my other smaller engines have no problem passing the switch track.  There is current going to the track.  Any thoughts would be appreciated.  dep

My dash 9's (railking) also mirrored your symptons over an atlas 7.5 but only at scale 3mph and under. I thought roller mods would provide the cure..they did not. RK six axle engines only have 2 wheels that are ground effective to the outside rails..plastic blind driver and traction axle do not provide ground path. I am in the process of changing the traction axles to solid non traction wheels. This problem doesn't exist with my premier 6 axle units as they have solid wheel sets front and rear at each truck.

 

That's good to know.  I am surprised that this would be an issue since you will always have 2 wheels solidly on an outside rail.  I suppose that dirty wheels or dirt/grease on the axles could be the problem.

Bob