I was thinking in terms of Atlas or Kato trucks on any cars used in one of these "mini" hump yards. I have a set of the Kato cement hoppers, and have found that when I use them when our modular club is set up, the floor of the building we set up in has to be "dead level." As little as 1/2 of 1% grade will set those things rolling unless they are deliberately derailed when switching.
Idea for a working "hump yard."
- Thread starter Russ Bellinis
- Start date
I am very sceptical about a working (and I mean WORKING!) hump yard on a model layout. So far I've seen four hump yards on club layouts, one with the air type and three with bristle type retarders.
Sorry guys - the actions on all of them looked extremely toylike. The cars started like a Formula 1 car at the top of the hump (or not at all). Then at the retarders it looked as if they had run into a wall. Some stopped there, others rolled on, picked up speed again and smashed with a scale 100 mph into the waiting cars down the track.
Ok, I admit, I added a little drama to my report.
But believe me, on every single hump yard the action was jerky, unsafe, random and unprototypical - nothing to admire, rather giving a painful impression... 
BUT: This was quite some years back. No computers then! Ray, if you think you can manage air retarders with the appropriate hard- and software, by all means try it. But it will be a major chore. I guess it could be a real research project (BTW: another possible facette of our great hobby). But - it won't be easy!
Like screwysquirrel put it, the main problem is the scaling down of the cars: The laws of physics are against us!
And the second problem is the difference in free-running of the cars. It is extremely difficult to get about the same degree of freewheeling in a whole fleet of freight cars. So you really had to treat each car on the hump individually. Perhaps this is possible with computerized sensors. A real challenge for all computer freaks, ain't it?
Ron
BTW: All four clubs rebuilt their yards to flat switching.
(And thank you Greg for your interesting explanations!)
Sorry guys - the actions on all of them looked extremely toylike. The cars started like a Formula 1 car at the top of the hump (or not at all). Then at the retarders it looked as if they had run into a wall. Some stopped there, others rolled on, picked up speed again and smashed with a scale 100 mph into the waiting cars down the track.
Ok, I admit, I added a little drama to my report.
But believe me, on every single hump yard the action was jerky, unsafe, random and unprototypical - nothing to admire, rather giving a painful impression... BUT: This was quite some years back. No computers then! Ray, if you think you can manage air retarders with the appropriate hard- and software, by all means try it. But it will be a major chore. I guess it could be a real research project (BTW: another possible facette of our great hobby). But - it won't be easy!
Like screwysquirrel put it, the main problem is the scaling down of the cars: The laws of physics are against us!
And the second problem is the difference in free-running of the cars. It is extremely difficult to get about the same degree of freewheeling in a whole fleet of freight cars. So you really had to treat each car on the hump individually. Perhaps this is possible with computerized sensors. A real challenge for all computer freaks, ain't it?Ron
BTW: All four clubs rebuilt their yards to flat switching.
(And thank you Greg for your interesting explanations!)
Amherst Model Railway Society in Springfield, Mass, has a large HO scale operating hump yard that works excellent using compressed air to retard the cars. They set it up every year at The "Big E" show in Febuary.I can sit there for hours and watch it. Never see them have a problem with it.
They use real short bursts of the air, and before it gets to the flat the give it one more quick burst.
They use real short bursts of the air, and before it gets to the flat the give it one more quick burst.
Ed, do you know if they have a website?
Would be interesting to see. Do you know if they use some sort of a) computer control, or b) freight cars with exactly the same weight?
Ray, now you're on safe ground - apparently it can be done! (And I still wonder, HOW??
)
Ron
Would be interesting to see. Do you know if they use some sort of a) computer control, or b) freight cars with exactly the same weight?
Ray, now you're on safe ground - apparently it can be done! (And I still wonder, HOW??
)Ron