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What have you done to make Walthers passenger cars run reliably on 24" radii?

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  • Member since
    September 2003
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Posted by Overmod on Thursday, December 3, 2020 11:56 AM

SeeYou190
Simply adding touching diaphragms to passenger cars, even though they never reached a point of interference, would make derailments more likely, and increase the drag on the locomotive.

Which way would they derail, and at what point in a curve?

  • Member since
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Posted by SeeYou190 on Thursday, December 3, 2020 12:13 PM

Overmod
Which way would they derail, and at what point in a curve?

I have to appologize, I really do not remember.

It has been a few years since I worked through all this, and since then I have made no forward progress on my passenger cars.

-Kevin

Living the dream.

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    December 2008
  • From: Heart of Georgia
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Posted by Doughless on Thursday, December 3, 2020 12:22 PM

If the curves are sharp, the middle sections of the cars...where the diaphrams are...wont be aligned near the beginning or end of a curve, probably at the end.

The lead car will be on the straight track and the trailing car still on the curve.  I would think that any obstruction that has a "push" tension would occupy the space the other diaphram wants to occupy as the curving car returns back to straight, therby causing a derailment.  Even if the diaphrams dont ever separate, I would think the diaphram on the lead car would have position over the trailing car's diaphram enough to possibly keep the trailing car from returning home.

Gentle tension, broad radius, and easements would keep the infighting at bay.

- Douglas

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Posted by richhotrain on Thursday, December 3, 2020 5:12 PM

ATLANTIC CENTRAL
 
richhotrain 
 
ATLANTIC CENTRAL
 
richhotrain 
Paul3

Overmod,
Thanks for the notice.  I edited my post and put in a direct link to the Hi Tech Details diaphragms.

One thing that I didn't bring up about touching diaphragms is the difficulty with uncoupling.  

I am less concerned about uncoupling cars with custom diaphragms than I am with the diaphragms causing derailments. I am curious about the effect of custom diaphragms pulling cars off the rails since the passenger cars are physically attached to one another. Is this an issue? 

Rich 

Not sure I understand? My diaphragms touch and are slightly compressed (very slightly), but the faces slide sideways on each other as required. But they never go completely past each other.

Yesterday was busy beyond belief, maybe tonight I can get some stuff out and take some pictures.

Uncoupling is not bad, a little hook will reach in/under and get the Kadee trip pin.

Sheldon  

What I meant, Sheldon, is that not only is each car "pulling" all of the cars behind it by means of a coupler, but once the diaphragm physically connects two adjoining cars, it seems to me that there is even more pull on each following car, potentially giving rise to derailments if the trucks on the following cars are pulled off the rails. Dunno, maybe that is not an issue. But to me, it is as if you have one long snaking passenger train, if you know what I mean. 

Rich 

OK, with the American Limited diaphragms the springyness of the diaphragm itself is amazingly light, unlike old Walthers paper diaphragms, or many of the plastic diaphragms I have observed on newer Walthers or similar passenger cars.

The diaphragms present no noticable resistance when coupling, they easily compress as needed to allow the couplers to uncouple, or to allow the couplers to work correctly when backing up.

The trick is getting the coupler position perfect, so that the diaphragm has the slightest compression with the train in tension, but still leaving most of the compressive travel of the diaphragm available for going around curves.

This is why trying to mix brands or types does not work.

The diaphragm is functionally two pieces. One piece is tabed into the other in the middle of the top and bottom. So the outer piece pivots allowing one side to move away from the car as the other side moves toward the car.

Additionally, the outer piece compresses straight in. The outer piece is sprung top and bottom by torsion bars, similar to the springs and rods on real diaphragms.

Using the long shank coupler set back on the car, minimizes the shrinking of the distance between the cars in curves, this gives the diaphragms more room to work.

Hope that makes sense, pictures may be the only way to really explain. Do you have any Proto2000 hood units, E8, PA, FA? Look closely at how those diaphragms work.

Sheldon 

OK, yes, that does it explain it better for me. Just to be clear, I was not suggesting that the diaphragms will cause derailments. Rather, I was just wondering if this could be a problem. Apparently, the diaphragms will not cause problems.

Rich

Alton Junction

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  • From: Maryland
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Posted by ATLANTIC CENTRAL on Thursday, December 3, 2020 7:08 PM

Here are some photos of the American Limited diaphragms up close.

This is one of my 72' cars coupled to an 80' Branchline Pullman, on a random piece of flex track. No idea what radius or how smooth the curve was, but I tried to show the offset condition you would have gong in and out of curves.

Currently I do not have any trackwork set up.

 

 

 

 

 

 

Sheldon

    

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Posted by hon30critter on Thursday, December 3, 2020 11:23 PM

Thanks for the pictures Sheldon.

Dave

I'm just a dude with a bad back having a lot of fun with model trains, and finally building a layout!

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Posted by richhotrain on Friday, December 4, 2020 5:04 AM

hon30critter

Thanks for the pictures Sheldon.

Dave 

Yes, thanks for sure. Those are very convincing photos.

Rich

Alton Junction

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