I have searched the forum and the internet and I found 100s of posts and or questions about couplers, but none answered my exact question. I searched MTL’s website and still didn’t get my answer! So either I can’t explain it right or what I’m looking for doesn’t exist but I swear I’ve seen it. So the question is a couple parts. First off I have 99% rapido couplers and most of, if not all are truck mounted. I have a few places on the layout with hard to reach places. By the time I get the cars uncoupled it looks like a horrible derailment scene locos and cars on their sides scattered everywhere! Everything off the track etc. So to fix that problem I took a little tiny switcher and cut the hook part off the coupler so I can push cars to these locations and then back away without pulling the cars back. Then I get them with an engine with an unmodified coupler. Everything seemed ok. Then my son in law bought me a new fox valley models NS engine and six cars with knuckle couplers. Now I have two different styles. That’s the first part of the question are all knuckle couplers the same? If not will they couple together? Then the main part of the question is, do they make a knuckle coupler that has that t shaped shank like the rapido that will mount into the rapido “box” with no modifications. I want to say I’ve seen them on the internet but I can’t find them again. I really don’t want to have to replace all my trucks if I don’t have to. I know I can make an adaptor car but I rather change everything to the same coupler if it’s reasonable. Thanks for any help and or advice.
Your problem with trying to uncouple rapido couplers is a common one. They couple well, stay coupled well, but are difficult to uncouple. There are/were uncoupling ramps for Rapido couplers. They pushed up the pins on the bottom of the Rapido couplers to raise them and uncouple them. The big problem is, you can only uncouple on the ramp, and you can't push a car off the ramp, or anywhere else, without recoupling to it. I like your idea about cutting off the hook part to make a "pusher" locomotive, very clever!
There is an old system for close coupling cars that rarely get uncoupled. It involved cutting most of the hook off leaving just a 'T' shaped piece sticking out. The other end of the same car had its Rapido coupler, spring, and metal retaining strap, all removed, leaving only the empty coupler box. A string of these cars could be coupled by lifting the empty coupler box end of one car over the 'T' end of the next car. (see photos of ore cars)
Micro-trains does/did make 'T'-shank couplers. They are used in locomotive conversion kits, and do fit into the loco's original Rapido coupler box, but usually involve inserting a M-T coupler box inside the Rapido one. These conversion kits are very expensive, and each kit only fits one specific locomotive.
I would suggest forgetting about Rapido couplers, and switching over to all Micro-Trains couplers. Yes, the easy way to do that for cars is to replace the original trucks with M-T trucks with their excellent couplers attached. Yes, the wheels that come in those Micro-Trains trucks are plastic, not metal. Micro-Trains wheels, plastic, or their new metal replacement wheels, are excellent and roll very freely. I don't think Micro-Trains offers their trucks with their newly-introduced metal wheels in them, at least not yet. I use Micro-Trains trucks, but replace the plastic wheels with metal ones.
That brings up another subject. If like me, you prefer metal wheels, you may want to keep the metal-wheeled trucks you have now, cut the Rapido couplers off them, and body-mount Micro-Trains couplers. Do you have any locomotives, or cars, that have their couplers mounted to the body, and not on the trucks? I suspect that new NS loco that came with knuckle couplers, has those couplers body-mounted. That seems to be the current trend. I have not seen a locomotive with truck-mounted couplers in years. Even some new freight ,and passenger, cars are coming with body-mounted couplers now. The thing is, you would need to decide,(If you were going to switch over to M-T couplers) whether to use those M-T trucks with the couplers already on them, or to body-mount M-T couplers and not pay for new trucks (reuse what you have) but only pay for couplers.
The thing to avoid is having some body-mounted couplers and some truck-mounted couplers. It needs to be all one way or all the other. Mixing the two mounting options is a worst case scenario. You are far more likely to have derailments, and coupling/uncoupling problems, if you mix the two. I suggest picking out a few of your longest cars and body-mounting M-T couplers on them, Then run the heck out of those cars and see if they cause any problems.
You asked if all knuckle couplers were compatible with each other. In theory, yes. In actual practice NO. I advise people to use whatever brand of knuckle couplers come on any new cars they buy, until those couplers cause problems. Then replace them with Micro-Trains couplers.
good luck, have fun;
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