shunted brushes

[dsmith]

Has anyone tried the shunt wire brushes in a postwar Lionel engine and did you notice any difference?  Shunted brushes have a braided copper wire molded into the end of the carbon brush.  This is supposed to increase conductivity by allowing the current to flow directly into the brush instead of through the spring/brush connection.  I used to race 1/24th scale high tech slot cars and they used shunted brushes but the current flow through the motors was extremely high (more than 10 amps at 12 volts) compared to 1 or 2 amps that my engines run at.

[lionelsoni]

Never tried that; but my guess is that the brass brush holders in (most?) Lionel motors would effectively shunt the brush spring, making any improvement unlikely.

[phillyreading]

Not sure if that will work but you can try it.  What I did with an Aurora H.O race car was to use the pick-up springs from a T-Jet 500(1966) in an AFX motor(1973) instead of brushes and I gained quite a few scale mph, so it may work.  The only problem that I can think of is that you may harm the armature brush contact plates in any long term use.

Lee F.

[sir james I]

I use them in all brush replacements. Solder the wires to the brush holder for a good contact to prevent arcing. As far as I know Lionel now uses that type brush in all of their AC motors.

[USNRol]

I would suspect the benefit to show up after many hours of run time as the inner wall of the brass brush holder becomes gunked up with carbon or whatever black stuff accumulates in motors.  The shunted brushes would continue to conduct unfettered and you'd see less performance drop-off associated with a motor in need of overhaul.

Roland