Lack of humping

[FJ and G]

With so many hump locomotives sold, why are hump yards so rare. In many years of searching, the only photo I can find on the internet is of a hump yard under construction:

http://www.railroadmuseum.net/images/Hump%20Yard%2040221a.jpg

[METRO]

My thought is that it's because of the difficulty of controling car speed off the hump. I wouldn't want to add one to my line because I'd be afraid of any damage my freight could take while crashing into eachother as they classified. If someone could make a model speed-retarder this issue would probably become moot, but until then, my rolling stock is just a bit too delicate to throw down a grade into eachother.

~METRO

[egmurphy]

They take a lot of space, model cars don't coast nearly as well as real cars so operation isn't as reliable as one would like, and car retarders are very difficult to model. There are a few reasons to start off with.


Regards

Ed

[Don Gibson]

Problems modeling a 'hump yard' are not the track (easy) - it's the 'rolling.

Once a car start's rolling how do you stop it?
Not all cars roll equally. Some stop halfway down.
Some bang and break couplers.

Real railroad's use retarders that gage the speed and computers figure out just how far and fast it needs to go.

[Anonymous]

A lack of humping is a good thing, David, at the animal shelter. Oh!!!, you mean railroad hump yards! Yea, they eat up a lot of space. As for car retarders, I vaguely recall one solution was a piece of clear nylon "wisker" sticking up between the track to scrape the bottom of the car to slow it down.
Maybe there's a use for old tooth brushes.

[Anonymous]

Oh....I thought......never mind!

[jwr_1986]

Our old club layout had a hump yard. Small tubes came out betwen the rails and they were hooked up to an air compressor, regulated of course. As the cars went down the nearly 40% grade the operator would open the valve as needed to slow the cars. Like real life there waasa a main and then secondary ones as the car made its descent. It was cool but huge.

Jesse

Wow I'm glad I caught that spelling mistake. i would have been booted off the forum. Whew.....

[Adelie]

I remember reading in some older planning books about various schemes to give cars a "boost" at the top of the hump to get them rolling. I'm not aware of anyone actually doing any of those, though.

Unfortunately, hump yards don't compress real well for modeling and, as others have stated, car performance (free rolling wheels) is far from consistent.

[gvdobler]

FJ and G

I ask that question awhile back and as you can see there are a lot of reasons why it would be difficult.

But it would be a lot of fun to operate and to watch.

I thought about under track moving magnets and satelite tracking GPS systems but none of my ideas seemed very likely. If anyone figures it out they will be heros.

Jon - Las Vegas

[Anonymous]

Just a thought, but could you use the old problem with metal wheelsets (axles attracted to uncoupling magnets) to some advantage here - energise an electromagnet under the track to different levels depending on how much you need to slow the car down. Only snag I can see is that they usually "kick" the car onwards as it passes, but I'm guessing with a little experimentation this could be solved. Most cars have a steel ballast weight inside that would probably work for this purpose. Just a crazy idea!

[jimrice4449]

I've got one! It's 12 tracks wide with the shortest track being 14 ft.
Two of the objections noted above are valid. Probably the more dificult is retarders. I tried a bunch of posibilities and most turned out to be more derailers than retarders. Credit for the solution goes to the late Ed Ravenscroft who, in the early fifties, came up with the idea of a shot of compressed air to slow down the cars. The yard he used it on was only two tracks wide and you had to pull the cars out by dragging them back up the hump but the retarder problem was elegantly solved. Of course you have to find a way to control the retarders. I lucked out and located some 12 VDC solenoid valves (from after-market smog control devices) which, after some tweaking would hold 35PSI of air pressure (well, pretty much hold it) that only cost about $1.65 each. Unfortunately,
as the ones I've got bite the dust I've had to canabalize one of the three banks of retarders to replace ones that go bad. One of my short term projects is to devise some kind of cheap, workable valve to replace them.
The other problem is space. A double ended yard takes a prodigious amount. In my case I have the luxury of a 25X26 building (since expanded by a 12X24 extension) dedicated to the RR. I run frt trains of 40-50 cars. The hump yard and it's adjacent arrival/departure yard take up the west wall. The crest of the hump is over the arr/dptr yard which gives me an elevation of +4" at the crest of rhe hump. The hump itself is on about a 2% grade and takes up 12 ft. The tail track from the arr/dptr yard is another 15 ft. (I break inbound trains in halves to hump). Add 4 ft. at the top and bottom of the yard to go from 12 tracks to one and another 15 ft for the lower end tail track (when putting a train together I double over half of the tracks for one half of the trains and then go back and do the other half). As you can see, when all the parts are tied together, I use up about a scale mile or more of wall. Now a lot of this could be reduced by shorter trains and trimming the length of the tail tracks, but you're still looking at a LOT of space.
But guys, working it's more fun than a barrel of drunk monkeys!

[trolleyboy]

You know this could be solved(the car slowing) by the DCC companies I'm sure they could make a system of wheel retarders like the real ones and electrically run them with DCC comands. Down side to this is it would be expensive but I'm guessing doable. Rob

[BRAKIE]

The club that I am a member of has a working hump complete with a 18 track bowl*.This hump is 18' long..The retarders uses air to slow the cars down by small plastic tubes.These retarders will only turn to a preset air pressure so there is no danger of blowing a car off the tracks or ending up with a runaway car by using to much air.Its easy to use and lots of fun.We use one magnet at the end of the hump on the slope that faces the bowl..
* A "puller crew" to make up the trains..All operation at the club is DC.

[dinwitty]

MR had an article on building a hump yard, you used air jets to slow the cars.
Building one takes some expertise and its a unique operation,
I built one, not completed, but I may be building a different one eventually.

Too many different cars with different rolling capabilities make a hump yard not always practical, you need good rolling trucks.

Its not for everybody, but if you got the gusto for it, go for it.

[trainboyH16-44]

I am thinking about building a hand propelled one. Pretty crazy, huh?

[Anonymous]

The club I am a member of is adding a hump yard to their new extentsion, it uses the old air method. When i was there last night they had a guy testing the air system with various freight cars. Looks like it needs a little tweaking.

[ericboone]

I know this would get a little expensive, but wouldn't it be possible to build a hump yard with multiple independently controlled blown air retarders and some sort of speed detector that could measure the speed of the car at various places. Then a simple program would be run that would fire an appropriate number of retarders based upon the speed of the car. The multiple retarders are simply multiple air lines controlled with multiple solenoids. The speed detector could be two infared occupancy detectors at a given spacing. Velocity is simply the time it takes to get from one sensor to the next divided by the distance between the detectors.

[trainfan1221]

A local model club has a hump yard that they run on their open houses. The car speed is controlled by air. It is very condensed and seems more for show than practicality. It is a neat feature, but I can see why it is not convenient for most model railroads.

[dinwitty]

car speed is determined by timing, air is on till a described time and is shut off, so a slow car isnt retarded. (no joking)

.

[IRONROOSTER]

In addition to the space required for the yard, you need a pretty big layout to feed the yard and then use all the trains you put together. Even with a lot of staging, we're talking a pretty big operation here. Even with compression you have to make it pretty big to avoid a caricature. For those of us with a home layout, do we really want to dedicate most or all of our space to one feature? Personally, I do not.
Enjoy
Paul

[BRAKIE]

QUOTE: Originally posted by IRONROOSTER

In addition to the space required for the yard, you need a pretty big layout to feed the yard and then use all the trains you put together. Even with a lot of staging, we're talking a pretty big operation here. Even with compression you have to make it pretty big to avoid a caricature. For those of us with a home layout, do we really want to dedicate most or all of our space to one feature? Personally, I do not.
Enjoy
Paul

===================================================================
Absolutely! The hump at the club requires lots of inbound trains..Of course these inbounds must be matched by outbounds in number.
Looking at the River View yard (Cincinnati on the club's layout) and looking at The Newcomb yard in Toledo which is flat switched there is no comparison in size.River View is twice as big due to the hump lead,bowl,inbound and outbound tracks.The whole yard including the hump lead,hump bowl switch lead and bowl is 34 feet along one wall..BTW including the engineer running the hump engines there is a "pin puller/hump master" to operate the retarder air controls plus the puller crew/yardmaster which of course is one member so we need 3 members just to operate the hump.Thankfully the hostler can flip a switch and get the inbound locomotives to the engine service area.

[nobullchitbids]

Not much more to add here; but, one point not made is that two cars cannot occupy the same track at the same time, which means eventually the classification tracks fill up. This creates an endless series of variables when the rolling characteristics of the several brands of trucks are added. Even were a modeler or club to switch to a single brand of truck (or hump only those cars which were of a single brand), there remains the problem of adjusting the roll to accommodate an ever decreasing track length.

Despite this, I have seen one hump yard which worked well: A club in New England, which would visit the shows on the N-Track principle (though in HO), had one which worked with compressed air regulated by speed monitors -- photo cells hooked into an oscilloscope which, through a computer, regulated compressed air for "braking." A little involved but extremely effective. And since the shows usually were held in gymnasiums, space was not a consideration, only loyalty of the members in terms of showing up with their modules.

[Anonymous]

Hump yards do not work as a model. Why? Simple physics! The mass (volume) of the car decreases as the cubic root while friction is linear. In other words the volume of a car is 660,776 (87.1 x 87.1 x 87.1) times smaller than a real car but the friction is only 87.1 as much. This explains the poor rolling characteristics of models when compared to the prototype, the mass of the car to friction ratio is 7,586 times less? Not very good ratio in anybodies book. We can build accurately looking models but the physics prevents them from operating in the same way as real cars. If they, the cars would not stay put but rather roll to the low end of the layout.

[BRAKIE]

QUOTE: Originally posted by duc1218

Hump yards do not work as a model. Why? Simple physics! The mass (volume) of the car decreases as the cubic root while friction is linear. In other words the volume of a car is 660,776 (87.1 x 87.1 x 87.1) times smaller than a real car but the friction is only 87.1 as much. This explains the poor rolling characteristics of models when compared to the prototype, the mass of the car to friction ratio is 7,586 times less? Not very good ratio in anybodies book. We can build accurately looking models but the physics prevents them from operating in the same way as real cars. If they, the cars would not stay put but rather roll to the low end of the layout.

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I don't know where you got your information about humps not working( from a misinformed Expert perhaps?)..Please tell that to the 47 members of the club I belong to..I am sure they will be most interested after they show you our working hump.[:D]

[jimrice4449]

You don't need much mainline. My yard, described above, is fed by a 38 ft. single track loop with two staging tracks. I also have a 5 track arrival/departure yard adjacent to the hump yard. I run frt trains that are 40 to 50 cars long, it's just that I don't run them very far!
What kind of RR has multiple tracks in every available space and runs many short movements with relatively, few cars? Answer, the average prototype yard or the average model RR. I think most model railroaders haven't considered the operational potential that lies inside yard limits.
I've got a really big frt yard operation on the lower level and psgr on the upper and I have enough operating potential to keep 4 or 5 people busy without leaving yard limits.

[IRONROOSTER]

QUOTE: Originally posted by jimrice4449

You don't need much mainline. My yard, described above, is fed by a 38 ft. single track loop with two staging tracks. I also have a 5 track arrival/departure yard adjacent to the hump yard. I run frt trains that are 40 to 50 cars long, it's just that I don't run them very far!
What kind of RR has multiple tracks in every available space and runs many short movements with relatively, few cars? Answer, the average prototype yard or the average model RR. I think most model railroaders haven't considered the operational potential that lies inside yard limits.
I've got a really big frt yard operation on the lower level and psgr on the upper and I have enough operating potential to keep 4 or 5 people busy without leaving yard limits.

So if understand your 2 posts correctly, you have a 938 sq ft layout that contains a humpyard and a 38ft mainline with 2 staging tracks and a second level for passenger operations. I gather that you really like yard operations and they make up most of your layout with the mainline just there to move trains in and out of the yard.

Not my cup of tea so to speak, but hey great if you like it.

Enjoy
Paul

[Cox 47]

The late Don Santel of Dayton Ohio had an operating hump yard on his layout. The layout was featured in MR and an Allen Keller video where he teases Allen Mc and his V&O about his working hump yard. Cox 47

[Anonymous]

For the bowl... what specifications do folks have? I've tried to find some data on this, to no avail. Or is the "bowl" really flat?

[FJ and G]

The bowl obviously isn't flat. It rises at the far end a bit so errent cars can't escape. I'm hearing rumors of hump yards. Pictures?

BTW, the rolling stock should roll, just tested my O scale rolling stock and it free rolls at 2.25% slope. No excuses!

[Anonymous]

I spent many hours observing the Frisco Hump Yard in West Tulsa, Ok. during my college days. Even the "big guys" make computer errors with damage resulting to rolling stock. Have you ever noticed the bulk heads of occassional freight cars, either bowed inward or outward? My question is how do you control the auto uncoupling while sending the cars down the grade so they reach the proper destination track? Is this done with magnetic uncoupling ramps? If, for example you wi***o send a "string" of cars to the same destination track, is it a "close run thing" thing to uncouple at just the right moment? As to the variations in the weight of each car; is that a problem? The whole concept is fascinating although "out of reach" for most of us.