Coil and Magnetic Couplers

[servoguy]

If you are concerned about wearing out the sliding shoe, put some oil on the control track control rails.  I think the problem is more wear of the plastic part of the shoe as it traverses switches and crossings.  I have some old cars that show some wear on the shoe.

[gunrunnerjohn]

I'm converting some operating cars to function with TMCC to avoid the issues of having to use an operating track.  So far I have the milk car, the log dump car, the target launcher, and the barrel car working with TMCC.

[nickaix]

Unless you intend to unload while moving, you can probably just back the train up slightly to re-couple the car. You have to sequence thru reverse before starting again anyway.

[lionelsoni]

Remember that the coils are effectively in series, with the car's frame and the outside rails as the midpoint between them.  I called for an isolated transformer, but one with a center tap to layout common would work the same way, giving each coil half the voltage.  The controller would need some rewiring at the least.

[ADCX Rob]

lionelsoni

Reading Rob's post, it occurred to me that it might be possible to get around this problem by activating the unloading with an isolated transformer connected between the shoes on the two trucks.  Each coupler would then get half the transformer's output voltage, which might be low enough to prevent uncoupling.

Any power supply that the coupler coils have no reference potential to would work.  This is easily duplicated on the workbench.

[ADCX Rob]

kgstones

Ahhhh, so the coil couplers are on trucks that have the shoes that also operate the dumping mechanism? 

Not necessarily.  The the 3469 & 3461 cars do not have coil couplers.  All coil coupler cars, operating or not, do have them.

kgstones

Are all coil couplers on trucks with shoes then?

No, the 3469 & 3461 operating cars , and dozens of others, do not have coil couplers.

kgstones

Can you uncouple say a 3459 without dumping the load?

Yes.  The controller directs the same voltage(whether track voltage or accessory voltage) to both shoes, activating the couplers, which are grounded to the chassis.  The solenoid activating the dump mechanism gets the difference the difference(potential) in voltage between the two shoes, which would be zero.

kgstones

One of the things I don't like about having a 6019 or similar uncoupling track on a main line is that every time one of the cars with the shoes goes over it the shoes are touching and rubbing on those extra sections of rail.  Sooner or later that's got to wear them out.

It takes a long time.  I have several cars, in use on the layout now since ~1971, & many more, and I've never had to replace the shoes.  It's easy to do, though(they break before they wear out, usually).

kgstones

I guess that's what the 6-65149 uncoupling track is for.  But then you can't uncouple a coil coupler at that spot.   Do I have this right?

Thanks, Mickey

Yes.

 

[lionelsoni]

Reading Rob's post, it occurred to me that it might be possible to get around this problem by activating the unloading with an isolated transformer connected between the shoes on the two trucks.  Each coupler would then get half the transformer's output voltage, which might be low enough to prevent uncoupling.

[kgstones]

Ahhhh, so the coil couplers are on trucks that have the shoes that also operate the dumping mechanism?  Are all coil couplers on trucks with shoes then?  Can you uncouple say a 3459 without dumping the load?

One of the things I don't like about having a 6019 or similar uncoupling track on a main line is that every time one of the cars with the shoes goes over it the shoes are touching and rubbing on those extra sections of rail.  Sooner or later that's got to wear them out.  I guess that's what the 6-65149 uncoupling track is for.  But then you can't uncouple a coil coupler at that spot.

Do I have this right?

Thanks, Mickey

 

[ADCX Rob]

The transition started in 1948.  Several items continued with coil couplers beyond 1950 until electro-mechanical replacements were engineered or the item was discontinued or redesigned with different trucks.

Any 5 rail operating track will work the coil couplers, 6019 included.  The couplers work off the same activation rails as operating cars that used them.

The disadvantage of the 3459 & 3451 vs the 3469 & 3461 is that on the earlier cars, one of the couplers will come uncoupled when the unloading mechanism is activated.  This wasn't an issue when this system was developed in the prewar era because the box couplers work by gravity and the train remained coupled when you released the "unload" button.   Not so with the knuckle couplers used in 1945 & after.

[kgstones]

In searching for various running stock it seems that around 1950 Lionel changed from coil couplers to magnetic couplers.  Is there an advantage in one over the other?  What operates the coil coupler and/or will a 6019 uncouple a coil coupler?  I've been looking at various versions of both the coal (3459 & 3469) and log (3451 & 3461) dump cars and have shied away from the 3459 and 3451 versions just because of the coil couplers.

Thanks to all as you guys have helped me a ton in the past.

Mickey