What’s the secret to locking cheap/weak/old coupers?

Zip ties and flush nippers 

Kaydee rubber bands. Wrap them around the coupler and it stays shut. Option 2 a dab of super glue.

I have been using some small rubber bands that I got at Michaels. They hold the coupler shut but they will still open on most of my uncoupling sections of track

is there a pin holding the knuckle back?  Maybe it is not up far enough, bend the bottom plate up a tad with some needle nose plyer, it just may be out of allignment.  i would do that before a perm fix.

Super Glue!  I have been using it for years on couplers that will not stay shut and all have held.

Good luck,

Don

I agree with the comments. Also have used black electrical tape. 

Lionel went through a period back in the mid- to late-eighties when about every third car had couplers that wouldn’t stay shut. They eventually fixed the problem, of course, but not until considerable frustration was felt!

DGJONES posted:

Super Glue!  I have been using it for years on couplers that will not stay shut and all have held.

Good luck,

Don

I did the same, cementing them shut with SuperGlue at the hinges = no problem afterwards.

FrankM

Small black zip ties. 

Another vote for small black zip ties

Black dental rubber bands. They are small enough, tough enough, and cheap enough. They hide really well. 

Most couplers can still be worked too.

I think the pins were kinda too short for a while on later PW.

I vote for super glue. 

I use the black rubber bands.  That way if I ever get energetic and decide to fix the couplers, I still can.

Very small black wire ties.  Also removable later.

My kids were in braces and I used the little rubber bands

back then clear no black (which would of been better)

worked  great also removable if long term fix desired 

Steve Taylor

Westfield P & S railroad

I use black "Duck" brand duct tape cut into thin strips.  It holds, and is removable. 

Thanks folks. I’ll play with super glue, or maybe order a bag of rubber bands. It’s the Christmas layout, so glue is probably easiest

gunrunnerjohn posted:

I use the black rubber bands.  That way if I ever get energetic and decide to fix the couplers, I still can.

I knew a guy who used hot glue for the same reason - it's not really permanent, he said.

For some reason I have had few failing couplers (fingers crossed). Some, though. Most I have been able to fix. The modern Lionel RS couplers are unfixable, it seems - and are way too long, anyway. I prefer thumbtacks. The Lionel PW design was almost brilliant, and no thumbtack or too-long shank. Still the best 3RO couplers out there, and I'm not a PW guy. Design and materials were the secret. Change any of it and the performance goes down. And did I mention the PW easily installed coupler kit when all else failed? Bend a few tabs and badda-bing, badda-boom - fixed. I've used them on Marx, Weaver, old 2-rail trucks, others.

Another problem can be that sliding shoe activated couplers going over certain switches can cause the coupler to activate.  This, in my case, is mostly true with my Atlas switch tracks.  I hate the sound of an engine smacking into the rear of a string of detached cars.  My stomach turned when I heard this happen to the rear end of my green 2400 observation car.  The sinking feeling came knowing that there was no rear coupler protecting the car from the engine's impact.  There was only a minimal paint chip as a result, but I imagined much worse until  I looked at the car.  Even this small damage was upsetting.  This vintage of cars I run are in high end collector condition so that pits my stomach.  I'm past worrying about the damage to the resale price; it's more the damage to what I consider vintage industrial art.

The solution that I came up with is to string small cable ties around the coupler plate and through the groove in the sliding shoe.  This elevates the shoe as well as acting as an insulator over the contact.  Elevating the shoe is important because sometimes having the shoe catch on modern track can rip it off.  Also the cable ties smooths out the groove in the shoe so that there a lot less edge in the shoe to catch on the track.

Alan

Ideally, replacement or repair.

I did spring replacements on mid 90’s Railking hoppers. There was a batch with weak springs that went out and MTH sent me the springs for free. 

Try pin adjustments next as was mentioned. Finally I have used silicone glue applied with a toothpick. Idea being you could take it off later but I never have. 

I been using small neoprene O rings for years available at flea markets, hardware stores, eBay etc. The couplers still open when you use the magnetic uncoupler track.

I put the largest nail set in my drill press, and leaving it turned off, use it like a rivet press to tighten the rivets.

There's nothing worse then wondering why the trains running faster when your not looking, then CRASH SMASH!

I have used the dental / brace rubber bands for weak couplers.  I had to buy clear ones  but a sharpie turns them black quickly.  I plan to try Alan's idea of the cable ties on the sliding shoes.  Seems that most of my issues are with operating cars and I hate to super glue them if the shoe is the cause.  

Can someone post a pic of this fix? Not sure I understand where to place the zip tie or rubber band or whatever.

I use zip ties but some you can't  tie so they Get super glued shut.