MTL couplers and the "inchworm" (slinky) effect

Mark Truelove Jul 15, 2021

  1. Doug Gosha

    Doug Gosha TrainBoard Member

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    I wasn't implying "whiskers" wouldn't work in N scale. I was just replying to the idea that the only purpose of the coil spring is to center the coupler.

    Doug
     
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  2. Inkaneer

    Inkaneer TrainBoard Member

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    Folks, all this debate about 'slinky effect' is useless. There are solutions available. If you use cabooses the retarder spring works. If you model the modern era with no caboose then you need the "Firefly Fred" This is a patented self contained truck mounted EOT that uses track power to light a blinking LED. The electrical pickups on the wheels provide the needed rolling resistance. Here is the URL for the facebook page:

    FireFly FREDs - Home | Facebook
     
  3. bill pearce

    bill pearce TrainBoard Member

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  4. JMaurer1

    JMaurer1 TrainBoard Member

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    I used to have an office window that looked out on the SP tracks that included a passing track on a very slight grade. As the 1:1 scale trains would come to a stop you could hear the bam-bam-bam-bam coming down the track as the slack was taken out of the train (or was it being put back into the train?). Slinky is prototypical, I've seen and heard it.

    Why did Kadee/MT never 'fix' this? Maybe because they had a patent for the coupler with the spring...maybe they never really saw it as a problem. I don't see it as a problem and even if a 'solution' (i.e. new coupler) came out, I'm WAY TOO invested in MT to change and that's all that matters to me. Sometimes 'good enough' is good enough...
     
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  5. acptulsa

    acptulsa TrainBoard Member

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    I finally found that picture worth a thousand words.

    [​IMG]

    Don't be too sure. A center screw or pin could be added to those. They might take up a bit more space as modified, but they'd couple and uncouple the exact same way. And you'd still have realistic coupler slack. What you wouldn't have is the slinky effect, which really is something quite different.

    They could introduce those tomorrow, you could buy cars so equipped, and you'd probably never notice. I don't know why MT didn't already do it. They'd work like the ones you have (minus the Variable Car Spacing "feature"), and work with the ones you have. When vids appear online telling my customers how to make my product behave, I really like to think I'd notice. The solution might cost a whole nickel a unit, maybe.
     
  6. Doug Gosha

    Doug Gosha TrainBoard Member

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    The "T" shank couplers aren't the ones to which people usually refer when talking about the slinky effect. It's the original MT-5 unassembled, MT-3 assembled (1025,1023) couplers with loop shanks with the spring enclosed in the loop.

    Also, could you explain the center screw or pin thing? I don't know what you mean.

    I don't think Micro-Trains had enough complaints to seriously invest money in a "correction".

    Doug
     
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  7. acptulsa

    acptulsa TrainBoard Member

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    Well, they would certainly produce that effect. I can't find a diagram of the 1023. Is it like the 1019?

    [​IMG]

    What I mean is that screw that the 1019 has, and HO Kaydees, HO McHenries, flipping horn hooks, and a whole bunch more couplers (including real ones) have that the T shankers don't.

    Of course, only these 1019-style things sabotage the goodness of center screws by running them through oblong holes. Leaf springs (whiskers, if you prefer) would be simpler and cheaper than those entrapped coils if they were molded in McHenry style, and work at least as well.

    Good!

    Hey, gang. If I patent an MT-compatible coupler which doesn't have this problem, anyone want to go in with me to get it in production?
     
    Last edited: Jul 19, 2021
  8. CSX Robert

    CSX Robert TrainBoard Member

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    The trains go bam-bam-bam coming to a stop and they go bam-bam-bam staring out, do they go bam-bam-bam while running along at track speed (if they do, you've? It's probably been said hundreds of times, and I'll say it again when someone says otherwise, but slinky is not slack action and is not prototypical. attach each car aoupler with a giant undampened spring then you'll get 1:1 slinky action. You also don't need slinky to get slack action - with a train of all Accumates and/or MchHenrys, you still get slack action, but no slinky.
     
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  9. acptulsa

    acptulsa TrainBoard Member

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    Sometimes, usually on a slight downgrade.

    I agree. Springs can cause an oscillation which slack cannot. On a long train, that can cause problems.
     
  10. CSX Robert

    CSX Robert TrainBoard Member

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    Ok, I should have said over and over and over again. Yes, slack goes in and out and different time throughout a run, but slinky action is prety much continuous, at least for periods of time.
     
  11. CSX Robert

    CSX Robert TrainBoard Member

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    The T-shank couplers shouldn't produce slinky action, when pulling, because the body of the coupler is pulling on the hard pocket. They would still slinky when pushing, though, when the coupler is pushing against the spring. I believe the 105 and 1016 body mount couplers are the same because the spring is on the other side of the post.
     
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  12. Doug Gosha

    Doug Gosha TrainBoard Member

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    The 1025/1023 couplers are basically like the 1019 without that long extension on the back. Also, the couplers would have to be completely redesigned for whiskers to work. The two halves of the knuckle have to be able to move independently and opposite of each other.

    Doiug
     
  13. John Moore

    John Moore TrainBoard Supporter

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    I have never noticed the slinky effect on my layout with running trains. It may be that I run short trains 40 cars or less and the current layout 30 cars and less. It also may be that I tend to put the heavier cars first in the consists running 40 foot boxes ahead of 28 foot ore cars. And also I run a mix of couplers mostly Kato couplers and MTs. I also have run power on the rear of the train with speed matched locos.
     
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  14. Inkaneer

    Inkaneer TrainBoard Member

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    It has been a long time since I held a McHenry coupler but if my memory serves me correctly the 'whiskers' only served to center the coupler. The coupler shank was one piece and all of the coupling and uncoupling action was in the coupler 'knuckle' itself and was activated by the exposed spring, just like the KD #5 HO coupler. This supposedly came out after the patent on the old KD #5 expired. There were three 'issues' with the McHenry. First was their size. They were much larger than the MT which was oversized itself. The second issue was that modelers objected to the visible spring although the same design was used on the KD No. 5 in HO and was well received there. The third issue was rarely mentioned. It involved the mounting of the coupler and the coupling distance between cars. It, like the Accumate and some MT's, had a hole in the shank that fit over a post or a screw. There was no T shank whereby the coupler could be used to replace older Rapido couplers. In addition the length of the shank from the mounting hole to the actual coupler was the same as the Accumate and longer than the MT 1015's. It did not need to be. A shorter shank plus darkening the actuating spring would have gone a long way for their acceptance by the N scale community. Offering a T shank would do likewise. As for the size, that may have been an engineering problem which may not have been solvable at the time but with advances in computer aided design and production since then the size could possibly be reduced. MT did come out with a scale size coupler which was initially greeted with much acclaim. However, they required almost perfect track work as their size was so small that any track irregularity could cause false coupling. I haven't heard anything about them in a long while.
     
  15. CSX Robert

    CSX Robert TrainBoard Member

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    Accumates work the same way as Micro-Trains and they use whiskers, one on each half.
     
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  16. acptulsa

    acptulsa TrainBoard Member

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    Oh. Sorry, guys. No patent.
     
  17. NtheBasement

    NtheBasement TrainBoard Member

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    I run 20+ car trains with all MTL trucks. The slinky effect is most pronounced at the back of the train. At slow (walking) speed the last car stops, jerks forward, stops, jerks forward... At faster speed it doesn't fully stop but the effect is still there.
     
  18. BoxcabE50

    BoxcabE50 HOn30 & N Scales Staff Member TrainBoard Supporter

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    Add a drag spring to one axle of the caboose.
     
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  19. CSX Robert

    CSX Robert TrainBoard Member

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    Actually, Micro-Trains, Accumates, and McHenrys all have very close to the same length shaft (Accumates are a hair longer and McHenrys are in fact just a hair shorter), one problem the Accumates and McHenrys share is the mounting post in the truck is farther out, causing the coupler to stick out farther. It appears this design was to maintain truck compatibility with rapido couplers because they still have the post in the back that the spring for the rapido mounts on, so they had to move the post for the Accumate/McHenry out. An additional issue with the McHenrys is the size of the head - even with the slightly shorter shaft length the end of the coupler is farther out if mounted on the same post.

    You can mount an Accumate coupler in a Micro-Trains truck and get a working coupler with no slinky, virtually the same coupling distance, and the coupler box will not "explode." Some people have done this with a lot of success, the problem is you've now got all of these Micro-Trains couplers that you spent good money for and aren't using. An additinal problem is you currently canot get buy Accumates alone, as in without the trucks, so again money spent on something you're not using. I've tried mounting the McHenrys in the Micro-Trains truck and they almost work, the coupling action works but the slightly shorter shank results in no side to side movemment of the coupler (you might could trim the front of the coupler box a little to fix it, I haven't tried that yet).
     
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  20. Shortround

    Shortround TrainBoard Member

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    Some real nice info before I can get into it. Thanks all.
     

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