"stiff" drivers problem solving

[Keusink]

I have, in the past two years, bought quite a few steam locos. There have been a variety of brands (including a bunch of Bachmanns). I have lots of 22" flextrack curves on the set, walthers DCC friendly #6 turnouts.

The locos with large drivers e.g. a GS4 and a J class (both Bachmanns), even a Hudson J1e (BLI), are having trouble staying on the curves and on turnouts. They do not step off the tracks at any consistent place, but rather randomly. It is not necessarily the wheelbase length, as I have a couple of fancy 2-10-2's (Heritage 2000s) that do fine. Bachmann Connies do fine with 4 drivers, but the Hudson with three is tempermental. Hence my suspicion of large drivers.

Does the play in the drivers loosen up with time and use? Is there anything I can do to accelerate the process? I have checked track and wheel gauges per NMRA gauge, nothing wrong there. I have also added weight to the pilot wheels of the Northerns, which helps the pilots but not the drivers.

A bit frustrating, as I don't want to scenic until I don't have to worry about derailments.

Help please


Chris

[ebtnut]

In essence, it depends on the amount of "slop" built into the mechanism.  Some models are designed with some degree of lateral play in the drivers which aids in getting them around tight curves.  Big drivered locos have a long wheelbase, and if there isn't enough play, they will bind or derail on tight curves.  As a for-instance, if you measure you may find that the driver wheelbase of the Hudson might be close the same as your Connie.   

[rogertra]

Number six switches should handily easily any of the locomotives you have mentioned.

Are you sure they are all number sixes?

Are your locomotives derailing while simply taking the left or right leg of the switch?

Or.

Are your locomotives derailing while negotiating a crossover between two parallel tracks?

Are you absolutely, 100% positive that every single one of your switches is laid absolutely perfectly with no humps and bumps, no twisting, not laid on a grade transition whether at the bottom nor top of a grade, no rail joiners not correctly joined etc., etc.?

As I wrote above, number 6 switches should give you no problems.  Most problems with switches are poor workmanship when laying them.

[K487]

Chris:

A couple of years ago on a model railroad forum (don't remember which but it could have been this one) someone mentioned the following, I did it, and it helped a LOT.

I only have Bachmann brand steamers (all Berks - beautiful locos) and I had some loco drive wheels act contrary and were binding some.  The fix was easy - loosen the 2 or 3 screws on the plate under (that holds up) the driver axles.  Many of these screws were too tight from the factory which greatly restricted the sideways movements of the axles and hence the drive wheels.  When the screws were loosened ( roughly 1/2 to one to two turns) my Berks go through my old Model Power #4 (about 18" radius) easily.

K487

[bobwrgt]

Also check the wires and connections between the engine and tenders. Do the draw bars float and move freely ? Side to side and up and down.

Bob

[Keusink]

Thanks all, for your replies. I will try loosening the bottom plates a bit.

I was wondering if lubricating the axles was possible and recommended? If so, I assume it should be with light, non-conductive oil but I would like that confirmed by someone who knows?.

Yes, I am sure they are number six turnouts. I do not think it is the installation of the turnouts; they were laid first, and the track was built off that starting point. And the location of the step-offs is not consistent nor confined to the turnouts. The step offs do not seem to be in any pattern or regularity. A loco can pass a given point six times with no pattern, and step off the track at that point on the seventh go-round.

I have noticed that the drivers on the Hudson are very rigid with almost no play, and with the GS4 and J class it is usually the first driver that is the problem child.


Does anybody lubricate their driver axles to increase the amount of play available for curves?

Chris