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Pax cars constantly decoupling

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Pax cars constantly decoupling
Posted by waltoney on Sunday, September 16, 2018 7:11 AM

My HO-gauge Walthers Superliner cars decouple when passing over the slightest undulation in the track. The shank heights are correct per the Kadee gauge. The problem is that the couplers slide up and down relative to each other because of the lever effect of the long cars, and they slide up or down off their neighbor.

I tried wiring the cars together, but that simply torques them off the rails when passing around even a 60" curve.

If only there were couplers with extra tall sides, the cars would stay coupled. Are there any such? Can someone suggest a procedure for modifying the couplers I already have?                        

Tags: Couplers
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Posted by MisterBeasley on Monday, September 17, 2018 11:28 AM

What brand and model of couplers?  Are they loose in their boxes or snug so they don't move vertically?  Honestly, how bad is your trackwork?  You may find that getting rid of the undulations makes other things work better, too. 

It takes an iron man to play with a toy iron horse. 

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Posted by BigDaddy on Monday, September 17, 2018 11:50 AM

Welcome to the forum

60" curves, wow, you are lucky to the space.

Did you build transitions into your grades?  There are couplers called shelf couplers.  I don't know it that would solve your problems.

https://www.modeltrainstuff.com/kadee-ho-118-metal-sf-shelf-whisker-coupler-medium-19-64-centerset-shank/?ne_ppc_id=1079742151&gclid=Cj0KCQjwof3cBRD9ARIsAP8x70Ow5bV85fgYuOvy8R_tQ9nC07cckd88bEmO6gykZIHW0eZXRgOSAFwaAqZ1EALw_wcB

Henry

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Shenandoah Valley

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Posted by waltoney on Monday, September 17, 2018 11:54 AM

MisterBeasley

What brand and model of couplers?  Are they loose in their boxes or snug so they don't move vertically?  Honestly, how bad is your trackwork?  You may find that getting rid of the undulations makes other things work better, too. 

 

 

They are whatever Walthers supplied, they are snug in their boxes, and the trackwork is good enough that freight cars have no problem negotiating the undulations. Adjusting the flatness of the track with thin cardboard shims fixes some problems but uncovers others -- it's a game of diminishing returns.

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Posted by SeeYou190 on Monday, September 17, 2018 12:08 PM

Welcome to the Model Railroader forums. Your first few posts will be delayed by the moderators. Please be patient with this and stick around and join the group.

.

If you cannot fix the vertical undulations, shelf couplers are a good fix.

.

-Kevin

.

Living the dream.

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Posted by jrbernier on Monday, September 17, 2018 12:24 PM

  Is this 60" radius or diameter?  I can run full length passenger cars on my 30" radius curves.  This is a mix of Walthers, Rapido, and Rivarossi cars.  I did replace any plastic couplers with metal Kadee couplers.

  I suspect you might have severe bumps at your track joints.   When I laid my track I tested with a GP9 and some 40' boxcars.  Larger 6 axle diesel, steam and passenger cars 'found' the issues with my trackwork!

Modeling BNSF  and Milwaukee Road in SW Wisconsin

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Posted by RR_Mel on Monday, September 17, 2018 1:13 PM

Welcome
 
I use Kadee #119 Scale Shelf Couplers on all of my passenger cars and they never uncouple accidently and still work over an uncoupling magnet perfect.  They’re smaller size is a bit closer to scale too.  I started out with the normal size #118 Shelf Couplers and later to the Scale version for aesthetics.  Both the #118 and the #119 are interchangeable with regular Kadee couplers.
 
 
Mel
 
 
My Model Railroad   
 
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I'm beginning to realize that aging is not for wimps.
 
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Posted by 7j43k on Monday, September 17, 2018 3:54 PM

waltoney

My HO-gauge Walthers Superliner cars decouple when passing over the slightest undulation in the track. The shank heights are correct per the Kadee gauge. The problem is that the couplers slide up and down relative to each other because of the lever effect of the long cars, and they slide up or down off their neighbor.

             

Put bluntly, your trackwork needs repair.  A "slight" undulation will not lift a car enough to uncouple.

If you think you have problems with the Superliners, wait till you try 89' flats.

You HAVE to go through your trackage and find all the problems.  The Superliners are doing a pretty good job of that for you.

Another way to find vertical problems is with a hacksaw blade (you can bend it for a curve).  Put the non-toothed side down on a rail.  You should see no light underneath.  It should not rock.  Now try another spot.  Keep going.  Adjust the track until the blade finds no more problems.

 

 

Ed

 

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Posted by maxman on Monday, September 17, 2018 5:05 PM

SeeYou190
Welcome to the Model Railroader forums. Your first few posts will be delayed by the moderators.

Off topic, but why do you always post that the first few posts will be delayed by moderators?  Since the post appears it seems clear that the post has passed moderation.  Not a criticism...I'm just curious.

Thanks

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Posted by BigDaddy on Monday, September 17, 2018 5:38 PM

Spammers join groups and then send everyone spam.  It happens quite frequently in nonmoderated groups.  I don't know if the have the patience to wait more than 1 or two posts. 

I have never gotten spam from this forum.  I appreciate that.  Getting to 10 posts was no problem for me, but then on the Internet I have a lot to say.   In person, I am the quiet guy.

Henry

COB Potomac & Northern

Shenandoah Valley

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Posted by PC101 on Monday, September 17, 2018 8:43 PM

Welcome Waltoney, For me the kadee shelf couplers work just fine for, if that perticular car wants-to-be a peskie 89' flat or one of those Flexi-Van Mark III and Mark IV flats. Those Mark III have the trucks closer to the coupler ends then the Mark IV so the Mark IV have a greater angle and the coupler faces tend to lift and drop at greater differance and uncouple/slip apart if the track is very so slightly off in level. I like mutli diesel long trains and that equals weight/tonnage, well poundage anyway. Now... those Kadee shelf couplers will give you a fit if you try to seperate two cars by hand and if you have a derailment the whole bunch will follow each other on to the ground. I just can't say that I have any trouble with my Passenger cars.       

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Posted by joe323 on Tuesday, September 18, 2018 6:14 AM

PC101

Welcome Waltoney, For me the kadee shelf couplers work just fine for, if that perticular car wants-to-be a peskie 89' flat or one of those Flexi-Van Mark III and Mark IV flats. Those Mark III have the trucks closer to the coupler ends then the Mark IV so the Mark IV have a greater angle and the coupler faces tend to lift and drop at greater differance and uncouple/slip apart if the track is very so slightly off in level. I like mutli diesel long trains and that equals weight/tonnage, well poundage anyway. Now... those Kadee shelf couplers will give you a fit if you try to seperate two cars by hand and if you have a derailment the whole bunch will follow each other on to the ground. I just can't say that I have any trouble with my Passenger cars.       

 

Aren’t shelf couplevers used on the prototype?

Joe Staten Island West 

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Posted by waltoney on Tuesday, September 18, 2018 7:03 AM

Looks like. Now, if only I could figure out how to post a very clear photo I took in Winnemucca last May...

joe323

Aren’t shelf couplevers used on the prototype?

 

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Posted by MisterBeasley on Tuesday, September 18, 2018 10:02 AM

I would worry that shelf couplers could lift the end of the cars up enough to cause a derailment.

On the other hand, go ahead.  You are in denial over your trackwork, and maybe replacing your couplers to no avail will convince you that you need to fix the track.

Really, nothing will bring you closer to trouble--free operation than trackwork that's as close to perfect as it can be.  And nothing will be as frustrating as tweaking rolling stock and engines to make up for marginal track.

It takes an iron man to play with a toy iron horse. 

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Posted by 7j43k on Tuesday, September 18, 2018 10:59 AM

A couple of weeks ago, I took a train of 89' flats equipped with scale-sized Sergent couplers:

 

 

to a Free-mo setup.  There were ZERO accidental uncouplings.

The modules were built by 4-5 different people (none of them me) to Free-mo standards.  There was a 10 track yard, a double-track wye, a 3-siding turning loop. And more.

 

Good track is important for good operation.

 

 

Ed

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Posted by RR_Mel on Tuesday, September 18, 2018 11:18 AM

My layout is HO scale and I have what I would say is good track work.  It is probably far from perfect but I can’t remember the last time I had a derail that I didn’t cause myself by doing something stupid.  Even with what I would call good track I still had problems with random uncoupling with longer cars, seldom in the same location.  I went with shelf couplers and the problem went away.
 
All of my freight cars are short (nothing over 50’) and all have body mounted Kadee 58 couplers, I don’t remember having a freight car uncouple on its own.
 
The random uncoupling was only with my Athearn Streamline passenger cars which all have truck mounted couplers.  I don’t have a clue why only those cars would randomly uncouple.  I had several Bachmann 85’ cars with the mechanism so that the body mounted couplers tracked the curves.  They were the worst for random uncoupling.  I no longer have them but not because of the uncoupling, the 85’ cars didn’t look right on my small layout.  Ten 85’ long passenger cars are too long for a small 10’ x 14’ layout.
 
I even tried mounting the couplers to the frames of the 72’ Athearn cars and that made the uncoupling worse.
 
I have all kinds and sizes of locomotives that never have any problems negotiating my track, they never derail so I don’t believe the track work was the uncoupling problem.  When I originally laid my track I used an aluminum yardstick and a 4’ metal level to insure the track was correct.  I went with over length transitions on both ends of my 3½% grade, 1/32” per foot.
 
The absolutely worst case of uncoupling was when a portion of the train was going up my 3½% grade with cars returning to the bottom at full speed.  On level track it wasn’t bad at all, just back up and go.
 
 
Mel
 
 
My Model Railroad   
 
Bakersfield, California
 
I'm beginning to realize that aging is not for wimps.
 
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Posted by waltoney on Tuesday, September 18, 2018 1:02 PM

The Free-Mo standard doesn't specify a tolerance for the "flat" connection at a module edge, so there could easily be mismatches from exact flatness. I'm really glad to hear that this kind of coupler mitigates the possible problems.Cal Zephyr coupler

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Posted by waltoney on Tuesday, September 18, 2018 1:10 PM

Cal Zepyhr coupler

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Posted by 7j43k on Tuesday, September 18, 2018 3:18 PM

waltoney

The Free-Mo standard doesn't specify a tolerance for the "flat" connection at a module edge, so there could easily be mismatches from exact flatness. I'm really glad to hear that this kind of coupler mitigates the possible problems. 

For Free-mo, trackwork quality is not specified in the standards.  But people who can't build quality trackwork either learn how or tend not to be invited back.  Or their modules are "assigned" to the branch line.

The "flat" connections at the module ends can be lined up very easily, though it does take a bit of time. 

So, yes, there could easily be mismatches.  But properly set up, there are no significant mismatches.  

As I demonstrated when I ran my train.  Using Sergent Type E (as shown in the photo).

 

 

Ed

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Posted by PC101 on Tuesday, September 18, 2018 9:06 PM

 It can be seen (though I never used them yet, but someday) that the Sargent couplers have less chance to slip up and down having a more tighter fit between couplers then the Kadees having more slop between knuckle and coupler body. Even with Kadees on a 'heavy' train with long cars (double and triple open auto racks loaded with first generation metal Classic Metal Works vehicles, now they are made of plastic) with out shelfs when taking out slack action a little to fast, the force and slightly sloppy couplers/box and slightly not perfect track at that one particular location you can slip them vertically apart. 

Oh, and stay away from those cheap all plastic Kadee look-a-likes, cut off their heads and throw them in a scrap gondola.   

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Posted by PRR8259 on Tuesday, September 18, 2018 9:56 PM

Well, I only had limited basement right-of-way available to me.  I have used Kato 26.375" minimum radius curves, later supplemented by Shinohara sectional track 30" and 32"? curves, and also Atlas flex track curves at 30" and larger radius.  I have run everybody's passenger cars and just about everybody's steam power, including some brass (both passenger cars and steam) on the layout.  Anywhere there were issues with kinks, I have fixed them.  There is no such thing as perfect trackwork.  It tends to move ever so slightly with temperature and time.

I like to test my trackwork by running trains flat out full speed as fast as they will go.  ANY deficiencies due to kinks, trucks screwed on too tight such that they can't handle a slight vertical kink, or coupler separation become immediately visible.  Then I fix the problem.

John

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Posted by 7j43k on Tuesday, September 18, 2018 10:31 PM

PC101

 It can be seen (though I never used them yet, but someday) that the Sargent couplers have less chance to slip up and down having a more tighter fit between couplers then the Kadees having more slop between knuckle and coupler body. Even with Kadees on a 'heavy' train with long cars (double and triple open auto racks loaded with first generation metal Mini Metal vehicles, now they are made of plastic) with out shelfs when taking out slack action a little to fast, the force and slightly sloppy couplers/box and slightly not perfect track at that one particular location you can slip them vertically apart. 

 

Happily, the Sergents slide up and down quite nicely when they're coupled.  If they didn't, the vertical forces could cause a derailment.  Also, they fit in the coupler boxes with the same amount of vertical slop as the Kadees.

I agree there's lots of slop in the Kadee knuckle connection.  That's one reason I prefer the Sergents.

I suspect the "slightly not perfect track" is not so slightly.

 

Ed

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Posted by ndbprr on Wednesday, September 19, 2018 4:38 PM

Most people I know do not switch out passenger cars but run them as a unit train. Therefore, there is no reason to have couplers between the cars.  I make a drawbar and screw one end to one car. Then I insert a screw in the othercar and cut off the head making it a pin to insert in the other end of the drawbar.  I also use drawbars between engines.  No one has ever commented on them as apparently it is not where they are looking

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Posted by PC101 on Wednesday, September 19, 2018 6:18 PM

7j43k
 
PC101

 It can be seen (though I never used them yet, but someday) that the Sargent couplers have less chance to slip up and down having a more tighter fit between couplers then the Kadees having more slop between knuckle and coupler body. Even with Kadees on a 'heavy' train with long cars (double and triple open auto racks loaded with first generation metal Mini Metal vehicles, now they are made of plastic) with out shelfs when taking out slack action a little to fast, the force and slightly sloppy couplers/box and slightly not perfect track at that one particular location you can slip them vertically apart. 

 

 

 

Happily, the Sergents slide up and down quite nicely when they're coupled.  If they didn't, the vertical forces could cause a derailment.  Also, they fit in the coupler boxes with the same amount of vertical slop as the Kadees.

I agree there's lots of slop in the Kadee knuckle connection.  That's one reason I prefer the Sergents.

I suspect the "slightly not perfect track" is not so slightly.

 

Ed

 

The ''slightly not perfect track at that one particular location" with the combination of the Mark IV cars wheel base (setting farther away from the couplers then the Mark III) will increase the vertical angles of the Kadees and with their shanks up-down play, the coupler knuckles slipped apart. Went to my LHS today looking for those Sargent couplers "not in stock" I really want to try some on certain cars. They look really good.

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Posted by 7j43k on Wednesday, September 19, 2018 6:28 PM

I think you want to order direct.  That's all I've ever done.

They used to sell them assembled.  Not anymore.  Assembling them is very easy when you know the tricks and have practiced.  My first one didn't work.  I've built another 50 since then, and they all do.  I disassembled the first one by dropping it into acetone, and found the problem, fixed it, and used it.

It's too bad they don't sell them assembled anymore.  It's a great way to convince people to use the product BEFORE they try to put them together.

There's a group you can join and ask questions:

https://groups.io/g/SergentEngineering

And, if you want, you can PM me, too.

Check the website out:

http://www.sergentengineering.com

Once you whip them/you into shape, they are way wonderful and beautiful.

 

 

Ed

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Posted by waltoney on Thursday, September 20, 2018 4:50 AM

I'm glad to report that Kadee 118 (shelf) couplers solve this particular problem for me. I've been able to move on to discover OTHER track problems that are within reach of my modest skills. Thanks to everyone here for your help and support.

The prototype also uses shelf couplers, I discovered. It may be the only reason that Amtrak stays on the rails east of Denver (just sayin')...

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Posted by AntonioFP45 on Monday, November 12, 2018 2:59 PM

This thread caught my attention.

I've read posts on various thread and other forums about modelers experiencing positive results with shelf couplers, so I'm interested in trying them out.

Since I operate with 24" radius (yes I know that's not recommended, but my space is limited)I've been employing the old trick of having a normal-length shank on the forward-facing end of each car, and longer-length shank on the rearward facing end.  How does this translate with the shelf couplers?

"I like my Pullman Standards & Budds in Stainless Steel flavors, thank you!"

 


PED
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Posted by PED on Monday, November 12, 2018 8:32 PM

waltoney

The prototype also uses shelf couplers, I discovered. It may be the only reason that Amtrak stays on the rails east of Denver (just sayin')...

 

I can relate to that. I just completed a two week trip on Amtrak and the portion east of Denver and into into Nebraska about beat me to death. I thought the SW Chief was rough in western KS and eastern CO but the Zepher east of Denver was even worse.

 

Paul D

N scale Washita and Santa Fe Railroad
Southern Oklahoma circa late 70's

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