LGB 20670 Track Cleaning Locomotive Help needed

[Charles M]

Have a 20670 with a burned up electronics card . The motors both function for movement and cleaning use. Has anyone tried to wire up the motors to use this engine without the card? We just need to be able to clean track and don't need the flashing lights and variable speed control capability. Could we use a large resistor to set the speed of the cleaning motor and do that ? We are using DC track power .

The cost of a new or used locomotive is not an option at this time. We have 7 loops of track to clean with a total of 2000 feet of track and cleaning by pushing a cleaning pad is not much fun .

Any ideas would be appreciated . Thanks in advance .

Charles M

 

[Neil Robinson]

Charles M - 26/10/2009 9:52 PM
Has anyone tried to wire up the motors to use this engine without the card? We just need to be able to clean track Charles M

Yes, I have and it worked O.K.!

If you read my topic on Low voltage circuits for lights, smoke etc. in this section of the forum you'll find one way, but for analogue only there is a simpler way which may well suit.
The recommendation is to set analogue track power fairly high on these locos to power the cleaning motor at a fair speed and reduce the speed of the loco by using the loco's speed control knob. The following is based on a simplification of this.
In the diagram the track motor will run slower than the cleaning motor in one direction due to the number of diodes in the red box minus one. In the other direction the track motor will run quicker and the cleaning motor will freewheel. Experiment with the number of diodes to get a reasonable speed difference, you'll still be able to use the controller to adjust the speed of both, but not the relative difference of speed between the two motors.
If the loco runs with the system in reverse just swap over the track power leads.
BTW the thermal trip is the one already fitted as standard.

 

[Charles M]

Thank you very much for the information. We will have to try this out.

Charles M

 

[Neil Robinson]

Charles M - 27/10/2009 2:59 AM

Thank you very much for the information. We will have to try this out.

Charles M

You're very welcome.
Doubtless you are aware of much, if not all, of the following, but I'll add it for the record.

LGB designed these locos to work with the cleaning wheels turning in the opposite direction to the drive wheels. This is achieved by connecting the two motors the opposite way round to each other.
Some folks don't like this and prefer to reverse the cleaning motor connections. This cleans the track much less aggressively, and arguably less effectively, and lessens the tendency for the loco’s front end to bounce around.
Personally I prefer LGB’s arrangement. I think any bouncing about is mainly due to differing wear between the two cleaning wheels, which can be caused by cleaning curved track, the tighter the radius the worse the difference in wear. One way to reduce this is to put the loco on the track in the opposite direction every few circuits of your layout.

 

[Neil Robinson]

I don't know much about DCC so I can't help directly with solving the problem but I have an idea of what may be causing it.
I think the track cleaning motor is running in reverse at full whack, as it should be, and the cleaning wheels are overcoming any forward motion of the loco's driving wheels.

 

[jacobsgrandad]

55.5 - 27/10/2009 11:40 AM

Might as well jump onto the bandwagon with this topic. I have an analogue track cleaner which works fine on analogue.

It will also run in both directions on DCC as a loco but when the cleaning function is switched on, it just runs backwards with the lights flashing but totally out of control.

Any ideas of how to stabilise this condition would be welcome

You can only turn the track cleaner on when it is running "backwards" i.e. one way. Not sure what you mean by totaooly out of control. Mine needs quite a high setting to overcome friction of cleanng wheels but I assume that is the design

 

[stevedenver]

i too have had the backward running issue once in a while
mostly on a grade/curve and when track is wet

now that its been posted, i am thinking now about reversing the cleaning wires -i am thinking this might be the trick while running the engine slowly -it actually sounds like a pretty good option as i too sometimes get the bounce

 

[mike]

no, its because, as you state, its a anolog loco, running on zero streching.. your running it on digical, run s fine, turn on track cleaning funtion, manulally, its runs off backwards.. its the cleaning wheels, they are getting more,grip, and power, as theres noi control over them, by the limet anolg on bord controls..it needs chipping to work correctly, on a digical track..

 

[stevedenver]

well i reversed the cleaning motor leads and it works nicely-does reduce bounce and stalling due to 'tug-of-war"

clearly it wont get as much cleaning action in in this direction as running opposite-but running it slower seems to make it about the same