The Usual Coupler Problem

[webenda]

I noticed that some Lionel and some Menards cars uncouple when running around the layout.
My six-pack of coal cars from Menards has one car that keeps uncoupling.
Here, that one car has uncoupled, and the Lionel engine uncoupled immediately after.

[webenda]

Here is a side view of a Menards coupler (on the left) and a Lionel coupler (on the right) that do not spontaneously uncouple.


And here is a side view of the Menards and Lionel couplers that spontaneously uncouple.

[webenda]

Here is the MENARDS mechanism that operates the knuckle pin. It does not fit tight against the bottom of the coupler and coupler shaft.


Here is what it looks like from the top when assembled.

[webenda]

A conventional repair using materials readily available but not necessarily the most technically correct solution.

[bluelinec4]

Those Menards couplers really are a pain and the only reliable fix is exactly what you did with the rubber band To make it less obvious you can use a black rubber band that kids use on their braces Very small and works good as you can still use the coupler. What most in the club did was use the small zip ties and they stay permanently closed The only couplers that do not have a problem are the older Atlas Master Line Lionel, Williams, MTH , RMT and Menards all like to deposit cars all around the layout

[webenda]

Lionel, Williams, MTH , RMT and Menards all like to deposit cars all around the layout

Thank you for the Braces Rubber Band and Small Zip Tie information, Ben.

[webenda]

[webenda]

Two toothpicks, a drop of super glue on the tips, wedged into the uncoupler slot.
--NOTE--
Hold the uncouple/couple mechanism tightly against the bottom of the coupler shank when driving the wedge in. (That is obvious, isn't it?}


I did not get the wedge in straight. It's too late now; I already breathed on the super glue, causing it to set up instantly.

The wedge was cut with wire nippers and sanded down with a Dremel sanding drum.


The uncoupler mechanism now snaps closed all the way.

Ugh, the truck has sanding dust on it now.

[Norton]

So the wedge trick worked? Good deal. I don’t have any Menards cars but now understand all the complaints about their couplers.
Also it doesn’t appear these can easily replaced to Lionel style couplers. I have a number of them from TMCC upgrades.

Pete

[webenda]

So the wedge trick worked? Pete

Yes, and it fixes the coupler to work the way the designer intended for it to work. It snaps open and snaps closed. No more sluggish half-closing of the locking pin.

But it is not as easy to implement as a rubber band (more about that soon.)

[webenda]

I have not gotten around to fixing more than one Menards uncoupler. But I did connect as many cars as will fit on a door layout to the Menards coal cars. Out of the six-pack of coal cars that I purchased, five have uncouplers.

The result of the train uncoupling when the engine is chasing the tail end of the train = a realistic-looking train wreck.


I was a little surprised to find a Lionel car with an uncoupler. It is Southern 539889.


Even more surprised to see that the truck/coupler is almost identical to the Menards truck/uncoupler on the coal cars.


And surprised again when examining the coupler pin mechanism... it closes all the way yet the coupler uncouples anyway.

Because the pin already closes all the way (and I do not want to drill the rivet out) I am going to do a band-aid fix (rubber band around the coupler shank.)

[G3750]

Nice fix, Wayne!

Isn't it crazy though that we're having these issues in this day and age?

George

[sarge]

Why not cut the trip pin off flush with the upper surface of the lever, drill and tap 1/72 or 0/80 (or whatever is appropriate based on the diameter of the pin you cut off), then you've replaced the pin with a screw driven up in deep enough to catch the knuckle reliably. If the springiness of the lever underneath changes over time, you can adjust it with a jewellers' screwdriver.

An adjustable metal trip-pin.

[webenda]

Why not cut the trip pin off flush with the upper surface of the lever, drill and tap 1/72 or 0/80 (or whatever is appropriate based on the diameter of the pin you cut off), then you've replaced the pin with a screw driven up in deep enough to catch the knuckle reliably. If the springiness of the lever underneath changes over time, you can adjust it with a jewellers' screwdriver.

An adjustable metal trip-pin.

Grand idea, Sarge.

Do you think the spring part is thick enough for the idea to work on these couplers? (Keep in mind, this plastic part is soft and slippery.)

[sarge]

Wayne, I think it'd be worth a shot.

It's not like you are using it as a fastener. A lot depends on the diameter of the current pin; the major diameter of the screw having to be smaller (unless you drill it out). Beyond that, I'm not convinced even that is critical. I'd bet the shear strength of a 0/80 or even a 00/90 is plenty for the purpose.

Not having one to hand to be sure, but you could even put a nut on the screw and drill a little into the base of the shank to clear if you have the depth available.

If it all goes sideways and the idea is a failure, just drill, tap, and drive one through the shank to capture the knuckle, making it inoperative (the same result you've gotten with an elastic band) and we've all learned something.

It sounds to me like everyone is depending on the plastic to flow to the full extent of the cavity in the mould that forms the length of the pin, and not caring whether it really does or not. Just assemble it, get it into the box, in the container, and on the ship to Long Beach.