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Thread: Cushioned - Spring Loaded Couplers

  1. #1

    Default Cushioned - Spring Loaded Couplers

    What is the purpose of this type of coupler ?

    Using them in my 2 DASH-9 + 100 US2Freight + 2 Dash-9 consist find that the front locos start moving, followed by the wagons in the consist one after the other, until eventually the last cars and 2 rear end helper locos start to move.

    Now that is not real, because if the rear helpers start accelerating at the same time as the front 2 locos, being controlled by the lead loco, as I imagine is the case now with modern technology, then the wagons at the rear would start moving at the same time as the lead and rear helper locos !

    The other side of the coin is that if only the front locos apply their loco brakes then the cars behind them would bunch up, taking up all the slack their spring loaded, cushioned couplers will allow, unless the rear helper controls are synchronized with the front locos.

    All that makes no sense to me ! If all couplers where "RIGID" like on passenger cars train sets like ICEs, TGVs and similar, then all units in a consist would start moving at the same time as it's locos and no messing ! ;-)

    O t t o

  2. #2
    Join Date
    Apr 2003
    Location
    Guyton, GA, USA.
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    Default RE: Cushioned - Spring Loaded Couplers

    Otto,

    The cushioned couplers are not intended for all car types in a train, except if it were a unit train of that type car. Even then, they would not be on a locomotive.

    I suspect that the reason that the rear locos don't "push" from the beginning is an MSTS programming issue. I think that MSTS just "adds" the total power of a consist to the "front" ( player locomotive ) of the train, and while it does seem to calculate cars individually, I think it handles helper locos as just more rolling stock, with the total power of the locomotives at the head of the train. Try a consist of only locomotives using Bill's locomotive coupler settings. You will see the same thing. It should be somewhat as you say, but, unlike passenger cars, freight cars do exhibit "slack" coupler action. Unless MSTS could be changed so that each locomotive exhibited it's power itself, we will have the delay in the rear helpers moving. No, that is not realistic, but it less so than a 100 car train with no slack action in it.
    Joe Morris, OVSRails Vice President
    OVSRails Engineer #2
    OVSRails
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  3. #3
    lelandfletcher Guest

    Default RE: Cushioned - Spring Loaded Couplers

    Dear Friends,

    When I was testing r0 values and coupler settings a few years ago, I had mid train helpers. The middle helpers definitely had power and effected the coupler slack just like the front engines.

    Yours truly,
    Leland

  4. #4
    Join Date
    Jun 2001
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    Baden, PA, USA
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    Default RE: Cushioned - Spring Loaded Couplers

    Hello Otto,
    A 100 car freight train of 100 ton loaded hoppers works out to be 20,000,000 lbs. In the real world, if you had a 100 car freight train with rigid couplers, you'd never move the train, just too much dead weight to move at one time :) Most freight trains are started one car at a time. I know you have been here to the states, if you watch a train that is being pushed up a hill closely, you will usually see a car that is floating. Basically you'll have the head end power pulling a percentage of the train (couplers stretched) and the rear end helpers pushing a percentage of the train (couplers bunched) With the car in the middle of this action floating back and forth. As the train crests the hill, you can hear the slack come out of the back of the train. This is something that Microsoft missed the boat on :(
    The idea behind Cushioned couplers is to dampen the run-in and run-out of slack action to reduce freight damage. The Cushioned pocket allows the coupler to continue moving forward while the car starts to move as well, to minimize that sudden jerk when a train starts.

    Take care,
    Rich S.

  5. #5

    Default RE: Cushioned - Spring Loaded Couplers

    Thanks, guys, teaching me some of the characteristics of US freight rolling stock.

    Every time I am visiting my son in Salt Lake City I intend to have a look at the UP marshaling yards there and the activity in them, having seen many 100+ trains going towards the South from a distance !

    Must remember to that the next time ! ;-)

    O t t o

  6. #6
    Join Date
    Apr 2003
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    Default RE: Cushioned - Spring Loaded Couplers

    Leland,

    I stand corrected. I was replying to Otto's observation. I had not really done any testing with helper locos. So, after your post, I did. I used identical consists except one had a rear helper engine. Using the extended F5 display, plus using the 2 and 3 views, I was able to determine that the rear pusher did start immediately. In view 2, I would move the throttle to notch 1, and as soon as the lead loco moved, I switched to view 3, and found the rear loco moving as well. Without the rear loco, the last car had a delay before moving. The only way that I got a delay with the rear loco was if I started the throttle, then released the brakes. With my braking setup, the front brakes release before the rear ones do.

    Otto, release the brakes fully ( using the extended F5 display to make sure all are released ), and after you are sure all have been released, then move the throttle. I think you will see the rear locos moving as quickly as the front ones.
    Joe Morris, OVSRails Vice President
    OVSRails Engineer #2
    OVSRails
    OVSRails Forums

  7. #7
    Join Date
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    Location
    Silicon Valley, CA, USA.
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    Default RE: Cushioned - Spring Loaded Couplers

    > A 100 car freight train of 100 ton loaded hoppers works out to be 20,000,000 lbs....

    Only if each car's friction line is set up correctly. :D

    Back to MSTS... You know with all the screwy friction lines floating around the only reliable way of knowing what kind of load you're dealing with is to take your consist and calculate the total newtons needed to get it all moving. Then, with some era specific assumptions, I think you might be able to work your way back to tonnage.

    [b]Dave Nelson
    SLW Route Design: The Cal-P, 1950.[b]
    http://i3.photobucket.com/albums/y51...cing_Genma.gif
    http://i3.photobucket.com/albums/y51...s/4ad3d633.jpg

  8. #8
    Join Date
    Nov 1999
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    Vancouver, BC, Canada.
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    Default RE: Cushioned - Spring Loaded Couplers

    Hi

    Years ago, I saw a train start with what must have been a very heavily loaded car with a Cushioned drawbar. These one piece end to end drawbars operate by having a shock absorber unit between the drawbar and the car body near the middle of the car. The only rigid connection between the bar and the car is via the shock absorber unit.

    The train did start moving slowly and I saw the car in front and the one behind both moving before the Cushioned carbody slowly started moving. This did illustrate how effective the Cushioning actually can be.

    GaryG

  9. #9
    Join Date
    Feb 2005
    Location
    Woodburn, OR, USA.
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    Default RE: Cushioned - Spring Loaded Couplers

    The cushioned drawbars work correctly. The helpers do push as they should and the rear cars do bunch up. By working your way up and down the train in the #2 and 3 views you can even see the nuetral node point work for and aft thru the train. The couplers even mimic RW coupling speed requirements for the coupling to "take". If you don't know US equipment and have not seen it run I don't see how you can say what is right and wrong. If the brakes are set when you start throttling from rest, the rear engines will not move until they overcome the remaining holding force of the shoes against the wheels. American trains at rest are almost never fully stretched to where the rear moves immediately after the head end. I never it ten years of running long trains out of freight yards got a train like that. You always start by moving one car at a time and many times my engines have moved two carlengths before the rear car started moving. When backing up to release stretch pressures so a car 80 cars back could be uncoupled, I've had to move more then two carlengths if the train had a lot of cushioned drawbars. The only American rollingstock that has no slack is Passenger and Roadrailer equipment.

    So far my attempts to introduce the MSTS community to realistic train charecteristics in the coupler area has been a disaster. For one I have people saying they are not realistic when they haven't even witnessed a real American train starting from rest much less having ten years experiance handling the real thing. I have had ex RW engineers state that they were going to reread their trainhandling rulebooks because their MSTS train finally handled like the real deal using my couplers. I have never said my couplers work perfect in all situations and have made numerous changes to correct these deficencies, asked experts their opinions on theories and had a full Beta team from an established vr test them. Otto says his coupler work perfectly when in fact on more then one occasion I diplomatically mentioned they did not concerning player pathing and switches and tight curves. I did not go into detailed screenshots and F5 values that are so small I can't even read them to prove my point to proclaim my couplers as the only ones that are flawless or perfect. I know Otto's coupler have issues because we completely converted a fleet of over 300 items to Otto's values and had all kinds of problems with them. They do work fine in a single fully playered path but when thrust into complex swithing activites with non defined paths all kinds of problems show up. I held my tongue out of respect for Otto's work even as he continuially complained that mine didn't do this or didn't do that or this is not right or that so you could do some Bin option that is totally unrealistic and never done in the RW here in America. All the while touting perfectly working couplers that have the most unrealistic of coupler traits that being of a solid one piece train. People complain that a tender doesn't have enough bolts on the side or the horns are wrong an a whatever engine somebody builds but nobody has said a word to the fact that these couplers stand in the face of american train charecteristics.

    I had gone as far as to start work with Mike Simpson on a universal slack coupler that Route Riter would put on all Noth American equipment and ones based on engine length along with a complex set of realistic brake templates that RR would automatically place based on car weight and engine weight and Ai's as well. People want more realistic trees, engines and rollingstock. I was just attempting to provide realistic couplers that made your train act as real as it looks and sounds. Nothing more. No fame or glory or recognition, just sharing my experiance and trying to make the sim more real. If you can't do something totally unreal with my couplers then they are successfully doing what they should do. BE REAL.

    I apologize for throwing the community into this longwinded debate. This is the first time in four years I attempted to share something I developed with the gracious help of some of the most respected members of the TS community and so far it's an utter failure. I will ask Mike Simpson to remove my templates from RR and if you want to run realistic North American trains then come on over to the Cascade and North Western vr. That fleet is fully equipped. I'm too exhausted from months of long days trying to make sure these work on all situations and as far as my concern from this point, it was wasted time.

  10. #10

    Default RE: Cushioned - Spring Loaded Couplers

    it wasn't wasted time, it just needs the right people to appreciate it.
    the only wasted time (and my personal bandwidth/space) was using those "perfect" couplers previously mentioned. I loved derailing all the time, just perfect...

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