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Coupling Resistance

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Coupling Resistance
Posted by Southgate 2 on Wednesday, October 6, 2021 9:30 AM

I was going to make this comment in the "Free Rolling" thread since it has come up there a couple times, but it's probably far enough off the original subject to be off topic.

A car's ability to couple freely rather than be pushed sown the track has more to do with couplers and not as much with weight of the car, grade, and lack of rolling resistance. All of the following is regarding already the exclusive use of Kadee couplers, not knock offs. 

With new #148s or other Kadee whisker couplers, or shiny new #5s in centered Kadee draft gear boxes, I can't MAKE a car roll down a grade without coupling at a decent slow approaching speed. If they don't couple, it's the couplers.

Off center: This happens mostly on rolling stock that has screw mounted draft (draught?) gear that can get turned out of center. Not aligned properly, no couple.

Coupler knuckle opening resistance: Somehow the knuckles have gotten gummed up, or even so old that a tiny bit of zinc pest  has made them tight. (rare, but I've seen it) Painting couplers can do it. If they don't swing upen freely, they won't couple consistantly. And delayed uncoupling is impossible.

Knuckle face resistance: If the face of the knuckle isn't shiny, but dull and flat, that will cause resistance to them slipping freely past each other on coupling. Again zink pest on some oldies contributed, but worse was when I once paiinted some couplers a realistic flat brown. I could push some of them all day until I slam coupled them.

Draft gear boxes: if the centering springs are restricted and the coupler can't swing laterally correctly and /or recenter properly, in both directions, that'll do it too. There have been discussions on making Athearn metal clips work better. I'll add that whisker couplers work better in these than bronze centering spring plates, but NOTHING improves a #5's behavior better than putting it in a Kadee box with the tapered out bottom plate, except a Whisker coupler in it's own box.  Blowing dust out with that canned stuff for computers can help.

A tough one, car length over the truck pivot to the body mounted coupler. The longer they are, the harder to couple on any sort of curve. I don't use truck mounted couplers, but all my cars are 50 scale feet or shorter. 

Coupling on a curve: Troublesome most anytime with body mounted couplers proportional tho the radius of the curve. I put uncouplers on straight track only, and keep the track straight where cars are expected to couple.

Horizontal misalignment: I've gotten away with this misdemeanor somehow more than I'd expect, but, yes, get that Kadee coupler  height tool out and make them consistant. Saves trip pin caused derailments too.

Use the genuine article, Kadee.  This has been driven into the ground enough. 

I recently went and changed out the draft gear boxes on all my Athearn tank cars, previously equipped with #5s in the Athearn box, for 148s in their own boxes. How nice it is to be able to use the delayed uncoupling feature with very consistant  operation! I'll add that #148s do an even better job in delayed uncoupling than #5s in general, but clean free moving 5s are acceptable.

These are my observations on my layout, but proven over decades of operation. I've probably missed some other contributing factors to inconsistant coupling, feel free to add them in. Dan

 

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Posted by Graham Line on Wednesday, October 6, 2021 4:28 PM

Coupling on curves I can't help you with, but installing the proper Kadee uncoupling magnet on your test track helps otherwise.

[In HO gauge, Kadee has coupling magnets sized for use with Code 83 and Code 100 rail. If the wrong height magnet is mounted in the wrong track, it doesn't work.]

Passing a car's coupler over the magnet shows me if the knuckle opens properly, and if the coupler swings correctly from side to side. Centering capabilities are a visual check.

This is why I won't allow the club fussbudgets to nip the iron J-shaped coupling pins off of the Kadees -- it takes away a testing tool that improves reliability.

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Posted by JDawg on Wednesday, October 6, 2021 6:33 PM

I have to disagree here. I have had brand new cars, with brand new kadees that will not couple PERIOD. I can increase the locos speed and then they will couple but at SS1 they just won't. Of course, my Alco S2 runs exceptionally slow. But I'm just saying, this, for me at least, happens for no reason other than the fact that the couplers have more resistance that the wheelsets. The couplers have this resistance for none of the reasons you stated above. They are just like that. Now, I just adapt to these cars and give them an extra bump when I switch them. No big deal.

JJF


Prototypically modeling the Great Northern in Minnesota with just a hint of freelancing. Smile, Wink & Grin

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Posted by gregc on Thursday, October 7, 2021 4:53 AM

Southgate 2
These are my observations on my layout, but proven over decades of operation. I've probably missed some other contributing factors to inconsistant coupling, feel free to add them in

wow, that's pretty comprehensive.

i'm just curious if a touch of teflon lube on the knuckle face would be helpful in some cases?

greg - Philadelphia & Reading / Reading

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Posted by mvlandsw on Friday, October 8, 2021 1:58 PM

Graphite or Neolube might adhere better and be less visible than teflon.

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Posted by FRRYKid on Sunday, October 10, 2021 2:48 AM

Southgate 2

Draft gear boxes: if the centering springs are restricted and the coupler can't swing laterally correctly and /or recenter properly, in both directions, that'll do it too.

I have sometimes found that sometimes when the coupler won't center properly, it's one of two things especially on couplers that have screw-on covers. Either a whisker has gotten caught under the cover or else the coupler cover is over tightened. And yes, I have done both more times than I care to admit.

Southgate 2

Horizontal misalignment: I've gotten away with this misdemeanor somehow more than I'd expect, but, yes, get that Kadee coupler  height tool out and make them consistant. Saves trip pin caused derailments too.

I have found this as well when recommended couplers for one car don't match up to the recommended couplers for another but yet the height gauge says they're right for the car. Good example: The coupler on the engine for my coal train didn't match up with the coupler on the coal car. Yet both are "right". Ended up changing coupler on the engine.

Just my experience as well.

"The only stupid question is the unasked question."
Brain waves can power an electric train. RealFact #832 from Snapple.
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Posted by cefinkjr on Sunday, October 10, 2021 11:23 PM

Southgate 2
Knuckle face resistance: If the face of the knuckle isn't shiny, but dull and flat, that will cause resistance to them slipping freely past each other on coupling. Again zink pest on some oldies contributed, but worse was when I once paiinted some couplers a realistic flat brown. I could push some of them all day until I slam coupled them.

Totally agree with your point about the face of the knuckle.  A few light, HORIZONTAL swipes with a file will remove the paint on the knuckle and allow much easier coupling.  Bonus: I don't recall ever seeing a prototype knuckle that wasn't a little shiny.

For the last several years, I have been painting Kadee couplers with no real problems when coupling.   The trick, I think, is to use the absolute minimum amount of paint -- almost a "dry brush" approach -- and very carefully avoid the 'hinge' at the coupler's wrist.  It probably helps, too, that I always flex the knuckle several times after the paint has dried.

One thing you didn't mention is the paint Kadee puts on the part of the coupler that's inside the draft gear box.  I've seen some that had very thick paint there.  Step 1 for me when installing #5s is to remove all of the paint from all surfaces that wil be inside the draft gear box.  This and a tiny squirt of graphite after assembly helps both the self-centering and delayed coupling features.

Chuck
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Posted by ricktrains4824 on Monday, October 11, 2021 1:15 PM

I have found, as I posted in the other thread, that some cars are indeed so free-rolling, that they move if you breathe in the vicinity. These cras, no matmer how much you adjust the couplers, will consistently run away from coupling.

These cars, along with all my Accurail/BB kit cars, all get added weight.

Once the cars weight forces the coupler resistance to no longer be a factor, the issue disappears.

Pease Note: I am in no way stating your tips are incorrect. They are all good to follow.

It's just sometimes, certain combinations, do not let these tips and asjustments work out enough. In those cases, you need to either -

A: "Slam couple", 

B: Use the 0-5-0 as a holder,

C: Have some kind of "braking" system, be it static grass, pins, axle wipers, etc...

or D: Add weight to the offending cars.

Three of these are not exactly prototypical, one depends on location, and sometimes the most prototypical are harder to do. So, where possible, and all other options are exhausted, add weight. When not feasable, sometimes the less prototypical option(s) are the only option(s).

Ricky W.

HO scale Proto-freelancer.

My Railroad rules:

1: It's my railroad, my rules.

2: It's for having fun and enjoyment.

3: Any objections, consult above rules.

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Posted by NHTX on Tuesday, October 12, 2021 10:48 PM

     I see the use of graphite recommended as a cure for various coupler problems.  I also use graphite to enhance coupler operation but, the method of application I use is different.  The good old yellow, No.2 graphite (lead) pencil.

    First of all my couplers get brush painted which sometimes "locks" them.  Once they have dried hard-at least a week, the knuckle swing is restored by prying it open, and attempting to wobble the knuckle pivot pin in all directions.  Once the knuckle opens and closes freely, with spring action alone, using the pencil, all portions of the shank that will contact the draft gear box, are treated with graphite using the pencil in a coloring motion.  The knuckle mating face is also treated in the same way.

       Graphite is also applied to the upper and lower inside surfaces of the draft gear box, that will contact the coupler shank, especially around the center pin.  I have found coupler problems to be nil, not requiring any 40 MPH collisions or chasing runaway cars at 65 MPH.

              

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Posted by ATLANTIC CENTRAL on Tuesday, October 12, 2021 11:06 PM

The only coupling resistance problem I have ever had is coupling semi scale couplers to regular original Kadee couplers.

That is one of the reasons I don't use semi scale couplers.

My cars are very free rolling but I have no problem coupling them gently.

Sheldon

    

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Posted by Southgate 2 on Wednesday, October 13, 2021 3:35 AM

Thanks for the input, Gents.   Ricky, In my opening statement, I don't know why I erroniously included weight among things that don't factor much. I very well know that weight DOES factor in, and add weight to all light cars.Embarrassed

JJF, your experience is as valid as mine. I should of added the o'l "your milage may vary" caveat.

Chuck, I didn't mention Kadee's own paint on them, cuz I've never noticed it. I'll watch for that too, or whatever else may interfere thickness wise.

NHTS, The #2 pencil idea is brilliant! I hope I'm not the last guy in the world to have heard of it, and I'll try it. 

Sheldon, I can't get good behavior from the semi scaled couplers either, nor do I try after first attempts. 

Thanks again, I got new stuff to look for. Dan

 

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Posted by Doughless on Wednesday, October 13, 2021 10:57 AM

JDawg

I have to disagree here. I have had brand new cars, with brand new kadees that will not couple PERIOD. I can increase the locos speed and then they will couple but at SS1 they just won't. Of course, my Alco S2 runs exceptionally slow. But I'm just saying, this, for me at least, happens for no reason other than the fact that the couplers have more resistance that the wheelsets. The couplers have this resistance for none of the reasons you stated above. They are just like that. Now, I just adapt to these cars and give them an extra bump when I switch them. No big deal.

 

This.  RTR cars out of the box will do this.

- Douglas

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Posted by ATLANTIC CENTRAL on Wednesday, October 13, 2021 11:49 AM

Doughless

 

 
JDawg

I have to disagree here. I have had brand new cars, with brand new kadees that will not couple PERIOD. I can increase the locos speed and then they will couple but at SS1 they just won't. Of course, my Alco S2 runs exceptionally slow. But I'm just saying, this, for me at least, happens for no reason other than the fact that the couplers have more resistance that the wheelsets. The couplers have this resistance for none of the reasons you stated above. They are just like that. Now, I just adapt to these cars and give them an extra bump when I switch them. No big deal.

 

 

 

This.  RTR cars out of the box will do this.

 

Do these cars have semi scale couplers? Are they real Kadee couplers? How many brands are actually installing actual Kadee couplers? Do you have a mix of regular head and semi scale head couplers?

The answers to these questions define your problems.

Sheldon

    

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Posted by Doughless on Wednesday, October 13, 2021 12:27 PM

ATLANTIC CENTRAL

 

 
Doughless

 

 
JDawg

I have to disagree here. I have had brand new cars, with brand new kadees that will not couple PERIOD. I can increase the locos speed and then they will couple but at SS1 they just won't. Of course, my Alco S2 runs exceptionally slow. But I'm just saying, this, for me at least, happens for no reason other than the fact that the couplers have more resistance that the wheelsets. The couplers have this resistance for none of the reasons you stated above. They are just like that. Now, I just adapt to these cars and give them an extra bump when I switch them. No big deal.

 

 

 

This.  RTR cars out of the box will do this.

 

 

 

Do these cars have semi scale couplers? Are they real Kadee couplers? How many brands are actually installing actual Kadee couplers? Do you have a mix of regular head and semi scale head couplers?

The answers to these questions define your problems.

Sheldon

 

Should have said new kadees into new RTR cars.  Walthers Proto appears to use kadees though.  Metal spring along the knuckle.

Installation is not that complicated.

The problem is the lack of wheel resistance to such a degree that it causes a car to free roll on a 0.25% grade.  

Can't couple on SS1 or SS2.  Gotta bang the cars more.

Kadee cars have Kadee couplers installed, of course.  But Kadee wheels and trucks on these RTR cars are some of the least free rolling RTR cars made.  Maybe they know something.

I've just installed kadees into old Walthers cars with the plastic wheels.  Kadees work great on SS1, but the cars don't roll very well.

- Douglas

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Posted by JDawg on Wednesday, October 13, 2021 12:36 PM

Doughless

 

 
ATLANTIC CENTRAL

 

 
Doughless

 

 
JDawg

I have to disagree here. I have had brand new cars, with brand new kadees that will not couple PERIOD. I can increase the locos speed and then they will couple but at SS1 they just won't. Of course, my Alco S2 runs exceptionally slow. But I'm just saying, this, for me at least, happens for no reason other than the fact that the couplers have more resistance that the wheelsets. The couplers have this resistance for none of the reasons you stated above. They are just like that. Now, I just adapt to these cars and give them an extra bump when I switch them. No big deal.

 

 

 

This.  RTR cars out of the box will do this.

 

 

 

Do these cars have semi scale couplers? Are they real Kadee couplers? How many brands are actually installing actual Kadee couplers? Do you have a mix of regular head and semi scale head couplers?

The answers to these questions define your problems.

Sheldon

 

 

 

Should have said new kadees into new RTR cars.  Walthers Proto appears to use kadees though.

Installation is not that complicated.

The problem is the lack of wheel resistance to such a degree that it causes a car to free roll on a 0.25% grade.  

Can't couple on SS1 or SS2.  Gotta bang the cars more.

Kadee cars have Kadee couplers installed, of course.  But Kadee wheels and trucks on these RTR cars are some of the least free rolling RTR cars made.  Maybe they know something.

 

 

I use only true kadee couplers. No imitations. I also use the standard size coupler, not the scale #158s. I do not suffer this problem on cars with plastic wheelsets, only on cars with metal wheel sets. I have fallen out of favor with the metal wheel sets because they make lots of noise while moving and lack enough resistance to couple to consistently. This is just my experience with coupling resistance. I'm not saying that I do everything perfectly, but I do know that everything is in gauge, installed correctly, yadda, yadda, yadda.

 

P.S. I'm not trying to start a fight with anyone, but I know what I know, and if I don't know it, I won't say it!

JJF


Prototypically modeling the Great Northern in Minnesota with just a hint of freelancing. Smile, Wink & Grin

Yesterday is History.

Tomorrow is a Mystery.

But today is a Gift, that is why it is called the Present. 

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Posted by Doughless on Wednesday, October 13, 2021 12:52 PM

JDawg

 

 
Doughless

 

 
ATLANTIC CENTRAL

 

 
Doughless

 

 
JDawg

I have to disagree here. I have had brand new cars, with brand new kadees that will not couple PERIOD. I can increase the locos speed and then they will couple but at SS1 they just won't. Of course, my Alco S2 runs exceptionally slow. But I'm just saying, this, for me at least, happens for no reason other than the fact that the couplers have more resistance that the wheelsets. The couplers have this resistance for none of the reasons you stated above. They are just like that. Now, I just adapt to these cars and give them an extra bump when I switch them. No big deal.

 

 

 

This.  RTR cars out of the box will do this.

 

 

 

Do these cars have semi scale couplers? Are they real Kadee couplers? How many brands are actually installing actual Kadee couplers? Do you have a mix of regular head and semi scale head couplers?

The answers to these questions define your problems.

Sheldon

 

 

 

Should have said new kadees into new RTR cars.  Walthers Proto appears to use kadees though.

Installation is not that complicated.

The problem is the lack of wheel resistance to such a degree that it causes a car to free roll on a 0.25% grade.  

Can't couple on SS1 or SS2.  Gotta bang the cars more.

Kadee cars have Kadee couplers installed, of course.  But Kadee wheels and trucks on these RTR cars are some of the least free rolling RTR cars made.  Maybe they know something.

 

 

 

 

I use only true kadee couplers. No imitations. I also use the standard size coupler, not the scale #158s. I do not suffer this problem on cars with plastic wheelsets, only on cars with metal wheel sets. I have fallen out of favor with the metal wheel sets because they make lots of noise while moving and lack enough resistance to couple to consistently. This is just my experience with coupling resistance. I'm not saying that I do everything perfectly, but I do know that everything is in gauge, installed correctly, yadda, yadda, yadda.

 

P.S. I'm not trying to start a fight with anyone, but I know what I know, and if I don't know it, I won't say it!

 

Fights usually start because one side can't accept the other's position.

I use either the standard #5 or have a few of the whiskers too. 

I would switch back to plastic wheelsets in a heartbeat, but my modern era uses almost exclusively cars with 36 inch wheels.  Only in the late Athearn BB days were there 36 inch plastic wheels.  I don't think that 36 inch plastic wheels exist in the market.

- Douglas

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Posted by doctorwayne on Wednesday, October 13, 2021 3:41 PM

JDawg
...I also use the standard size coupler, not the scale #158s. I do not suffer this problem on cars with plastic wheelsets, only on cars with metal wheel sets. I have fallen out of favor with the metal wheel sets because they make lots of noise while moving and lack enough resistance to couple to consistently. This is just my experience with coupling resistance....

 

I've been using Kadee couplers since the mid-'50s, and have used various versions of them over the years, including the semi-scale ones.  I don't have too many issues with coupling, but do agree with your comments on metal wheels, especially the noise factor. 

If I buy a car or kit with metal wheels, I do tend to keep them, but I don't like the racket they make, and I also don't like the shiny- and overly-wide wheel treads, as they draw one's eye to that very out-of-scale feature. 

Even the narrower "semi-scale" metal wheels don't look right, as they exaggerate the gap between the face of the wheel and the back of the sideframes. 
On real freight cars, the outer face of the trucks' sideframes are nowhere near the same width as the car-body they're carrying.

Perhaps if I'd noticed this earlier, I would have opted for Proto 87 standards, but it's a little too late for me to make that change.

As for free-rolling characteristics, check out this LINK which will take you to the last page-or-so of an otherwise fairly lengthy thread regarding modifying and detailing freight cars.  The performance surprised me.

Wayne

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