What is the distance between coupled freight cars?

[wcfn100]

All 5 of these car drawings specify Duryea underframes.  But, the photographs as well as the drawings do not look unusual for the period.

Okay that's what causing the bit of extra distance.  Something like a generic  flat car that would normally have a striker plate set 6" from the sill will be more like 11" with the Duyrea frame.

Thanks for posting all that.

My guess would be that the ORER does not include the distance from the striker plates to the coupler face in its "outside length" measurement.

The ORER lists the length between coupler pulling faces is it's "outside length"

It think I was having problems finding the exact cars from the B&O classes you posted so I'm not going to worry about the measurements I had found.  The Duyrea frames clears it up for me.


It should be noted that cars can be much closer as well.  The Type 21 tank car drawing I posted on another thread shows 30" between striker plates (of two tank cars together) but the striker plate is basically a 5/8" late against the sill.  So a couple tank cars may only be 31" apart.

Jason

[wcfn100]

The drawings in this book do not give dimensions that allow calculation of coupling distances between the heavy weight passenger cars.

I noticed that too while researching my coupler pockets.  No mention of coupling distance on any of the drawings I have.  If you fond something, I'd love to see what it says.


Jason

[Maletrain]

So, when trying for prototypical spacing of freight cars, would be assume that the transition period cars were mostly Duryea frames or not Duryea frames?  The difference is probably noticeable, being about 1/16" between cars in n scale.  And, with things like truck-mounted couplers on so many models, we can't just look at a model and know what its prototypes' striker distance was - it would take some real research to know for every "foreign" car on our model railroads.

[wcfn100]

it would take some real research to know for every "foreign" car on our model railroads.

Yep, and it all starts here. 

But I think that the B&O was a bigger user of Duyrea frames vs. most other railroads (that's how I even knew to ask).  In my head, it's the anomaly.  But maybe not.  Maybe it just doesn't show up as much within the 6-8 roads I research primarily.  Plus much of what I have drawings for are not home built cars, but from larger private builders like Pullman. 

Jason

[Mark5]

One of us should get out to a museum with a tape measure ... 

[nkalanaga]

Maletrain:  The 2.5 inch difference is the thickness of the knuckle.  Coupled, the knuckles overlap, so the coupled difference is less than twice the overall coupler length.

That's why, as Jason notes, the usual "in train" length is "over pulling faces", the inside surface of the knuckle.

[Maletrain]

Maletrain:  The 2.5 inch difference is the thickness of the knuckle.  Coupled, the knuckles overlap, so the coupled difference is less than twice the overall coupler length.

That's why, as Jason notes, the usual "in train" length is "over pulling faces", the inside surface of the knuckle.

The drawing in the Kalmbach Cyclopedia showes the 15" from the coupler pulling face to the striker plate, but that is for a steam locomotive.  So maybe that is different for freight cars?

[nkalanaga]

Good question.  There were non-standard coupler lengths, so it's possible that a locomotive could be different.  Or, maybe, at least one of the sources got confused.  I have no idea.