Skip to main content

Replies sorted oldest to newest

O gauge manufacturers tend to make the gap between cars larger than scale. This is due to the extra room required for clearances on O-27  (and even O-72) curves. Remember, these all started out as toys! That said, some of today's manufacturers have made provision for tightening the spacing and using K-D couplers.  Speaking of which, the normal "lobster claw" couplers we are accustomed to are massively over sized. You can thank the Lionel corporation for that. I suspect they did it to allow for easier uncoupling by children.

 

Chris

LVHR

Hot Water posted:
PRR 5841 posted:

Fellas,

Is there a standard distance between these cars?  If not, what would be typical?

TIA

Are you talking about the steam era, prior to cars being equipped with those long "cushioned underframe" draftgear assemblies?

Yes, 1940’s to be more specific.  I’m not sure that there is a standard like EMD F units, 3’ between units.  

Last edited by PRR 5841

Well, I can't tell you for sure abut O scale, but in S Scale with Kadee couplers it measures out to about 3 scale feet, regardless of model manufacturer.  It would also seem to be about right for the prototype.  After all, the brakemen shouldn't have to be Olympic-class broad jumpers to cross from car to car.

Illustrated are Pacific Rail Shops cars, the equivalent of O Scale's Intermountan:

DSC01841

Rusty

Attachments

Images (1)
  • DSC01841
lehighline posted:

O gauge manufacturers tend to make the gap between cars larger than scale. This is due to the extra room required for clearances on O-27  (and even O-72) curves. Remember, these all started out as toys! That said, some of today's manufacturers have made provision for tightening the spacing and using K-D couplers.  Speaking of which, the normal "lobster claw" couplers we are accustomed to are massively over sized. You can thank the Lionel corporation for that. I suspect they did it to allow for easier uncoupling by children.

 

Chris

LVHR

Could it be because they STILL are TOY TRAINS? Maybe you should take a look at 2 rail.

Simon

 

Basically, the distance between coupled cars is basically the length of two coupler heads plus the amount of draft gear travel on each car and the thickness of their striker plate castings.

Draft gear spring travel before the time of super-cushioning and extended draft gears from the late 50's onward, was about 3 1/2 inches or so per car.  About 6 inches of travel for cars with Duryea cushion underframes, introduced in the 1930's. They were no longer allowed for interchange by the 1960's as not all roads had the equipment needed and expertise for repairing Duryea underframes,

Often omitted on many models is the striker plate casting, through which the coupler shank passes under the end sill to the draft gear.  On many models I see use the little flange on the end of the Kadee coupler lid for that,  when it should be at least 1/16 (3"scale) out from the end sill or car end sheet. I use pieces of 1/16" square styrene for that, cutting the ends on a taper to match the Kadee lid.   

The Weaver B&O wagon top box car needed a bit more detail than that.  The couplers extend farther out, following Duryea  design. The detail helps fill in the gap under the end sill, and models the cast steel end sill bracket holding the end of the center sill and coupler mount. 

The Duryea does not have draft gear a such. The car body is isolated from center sill. On impact, or slack run-in and run-out the car body can shift back and forth up to 6" on the center sill, being held in place by spring nests on the inner face of the bolsters.  The space between this casting's face and the back of the coupler head is 9" on the prototype.  Notice the crack in the end sill bracket/carrier casting, caused by impacts over along time.

S. Islander

 

 

Attachments

Images (4)
  • 043X: A Zimmer/AllNation kit, built in 1976. It models Mount Vernon-built cars the Rio Grande bought in the late1920's.
  • 199: Rebuild of a 1942 Athearn car found as a 'junker' in 2018.
  • WT Duryea bracket: Adding Duryea carrier bracket/striker plate detail to a Weaver model in 2011.
  • coup03: Prototype wegon top box car end sill bracket/carrier.
PRR 5841 posted:

Fellas,

Is there a standard distance between these cars?  If not, what would be typical?

TIA

There are AAR (ARA and MCB back when) standards involving draw head heights  as well as other car building standards.   The distance would reflect the type of draft gear and coupler casting being used.

This would be a great question to be asked on the Steam Era Freight Cars Group.  There is much expertise on there for factual answers for questions like this.    

Unfortunately the compromises of our larger life tight radius curves impact on what type of model draft gear and couplers we use.  


BTW anyone catch the road name on Rusty’s picture of the S scale cars?

Bet the fellow immortalized in one of those cars would have the answer to this question in 1/4” scale. 

Add Reply

Post
×
×
×
×
Link copied to your clipboard.
×
×