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[Desert Rose]

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[jward]

I am a little confused as to how adding knuckle couplers to talgo trucks is going to improve their operation during switching. You haven't eliminated the main drawback of these trucks, which is their tendency to skew sideways every time you back them up. Even on good track that's a recipe for derailments.

[Len]

I'm with you Jeff. If you're going to pay for the Kadee #5's or #148's that come with coupler boxes, why not just body mount them and be done with it?

Len

[Len]

The original trucks can still be used after removing the 'arm' holding the horn-hook coupler box.

Len

[jward]

The original trucks can still be used after removing the 'arm' holding the horn-hook coupler box.

Len

You're right. In many cases the truck frames themselves are usable. I've done many such conversions over the years, and they've generally worked well with proper wheelsets.  As a matter of fact, the Mantua cars featured body mounted couplers, with a modified Tyco style snap in truck. I've never had problems with those.

[jward]

I think you got your forces wrong here. The up and down force you describe isn't innate to backing, but a reaction to the true forces at play when backing talgos.

When backing freight cars, the couplers will swing to one side. This exerts sideways pressure. With body mounted couplers, this force is transmitted through the car itself, and its effect on the trucks is to push the wheels against one rail. But the wheels themselves will stay in alignment with the rail they are pushed against. With a talgo truck, the sideways force the couplers exert will be transmitted to the truck itself, with the talgo arm acting as a lever to multiply that force on the truck. The wheels are now skewed, and riding against the rail at an angle. They are looking for any irregularity or flaw in your trackwork as a place to climb the rail. This rail climbing action is the upward force you described, and it is caused by the rail itself, not the truck. Switchpoints and frogs are perfect places for this to happen, as are rail joints or places where the track is slightly under guage. In the case of frogs, in theory the guardrails would prevent the truck from derailing, but most commercially made switches have guardails and flangeways that are wider than NMRA tolerances. And switchpoints are often stamped pieces of metal mass produced, rather than actual rail tapered to a sharp point. These are just the sort of flaws that cause derailments with talgo trucks, and the more cars you are trying to back, the worse the problem becomes.



 

[trainman203]

I never had good operation with truck mounted couplers when I had them. To me they are one of the markers of the boundary between toy trains and Model Railroads. The day the last ones left the layout was cause for celebration.

A model railroad supposedly represents greater realism, which includes operations backing up. Real trains back up. They don't run in circles, with the possible exception of orphan railroad unit trains that run only from mine to power plant then back. Talgo trucks largely preclude reverse operation since they chronically derail at every molecular rail deficiency.  And by default are best suited to circular running toy train operation.

Talgo trucks are a manifestation of economy of manufacture, a real indication of the market that the car is intended for.  Along with the cheesy oversized flanges that these trucks often carry, model railroad operation demands a finesse in design and manufacture that represents an added cost.  Since the majority of toy trains run in circles, never back up, and are often only run a few times before being disposed of, refinement of the product is an expensive option that can be bypassed in favor of profit.

And, as Jeffrey said, putting Kadee couplers and scale wheels in Talgo trucks basically amounts to putting perfume on a pig. I'm sorry to say it, but these cheap trucks have no place on anything but a Christmas tree railroad.