Easy on the brakes!

What the hell.....what is with these locomotives that when you apply 1% of pressure, and release it after 1 second, the speed continues to drop??? One example was yesterday on the Tehachapi Route. 96 tank cars, 8 SD 40's. I was going 22 mph and wanted to slow down for a crew change. I applied 1% of presure, and re-leased them after the speed dropped to 21mph......The train dropped all the way to 8mph before slowly picking up a bit more speed, and the same thing happened today with the NALW C-42-8 CNW with 80 doublestacks and 4 other NALW units going through Tehachapi. I applied the brakes, and once again, the train went from 42mph to 26mph in .02 tenths of a mile before "coasting" and picking up a bit more speed.This is very annoying to say the least. Is there anyway to modify this easily so it takes longer to slow down without briging the train to a grinding hault?????Chris Bogley
chrisb@tailsnrails.com
Ft. Huachuca AZ
www.tailsnrails.com Tehachapi Pass II review at www.msnusers.com/MSTSTehachapi

Alert | IP

Printer-friendly page | Edit | Reply | Reply With Quote | Top

RE: Easy on the brakes!!!!!, chucksc, Jun-15-03, 11:54 PM, (1) RE: Easy on the brakes!!!!!, CharlieB, Jun-16-03, 01:36 AM, (2) RE: Easy on the brakes!!!!!, derekmorton, Jun-16-03, 05:22 AM, (3) RE: Easy on the brakes!!!!!, sd70mac666, Jun-16-03, 07:37 AM, (4) RE: Easy on the brakes!!!!!, derekmorton, Jun-16-03, 07:42 AM, (5) RE: Easy on the brakes!!!!!, Stooopid_person, Jun-16-03, 09:27 AM, (6) RE: Easy on the brakes!!!!!, b101uk, Jun-16-03, 10:20 AM, (7) RE: Easy on the brakes!!!!!, sd70mac666, Jun-16-03, 11:13 AM, (8) RE: Easy on the brakes!!!!!, plainsman, Jun-16-03, 12:58 PM, (9) RE: Easy on the brakes!!!!!, xlspecial261, Jun-16-03, 04:15 PM, (10) RE: Easy on the brakes!!!!!, CGW409, Jun-16-03, 05:22 PM, (11) RE: Easy on the brakes!!!!!, xlspecial261, Jun-16-03, 08:00 PM, (12) RE: Easy on the brakes!!!!!, heffed, Jun-16-03, 09:26 PM, (14) RE: Easy on the brakes!!!!!, slyone, Jun-16-03, 09:56 PM, (15) RE: Easy on the brakes!!!!!, derekmorton, Jun-16-03, 10:48 PM, (16) RE: Easy on the brakes!!!!!, slyone, Jun-17-03, 01:09 AM, (17) RE: Easy on the brakes!!!!!, GP15Dash1, Jun-17-03, 08:06 PM, (23) RE: Easy on the brakes!!!!!, JonN, Jun-17-03, 07:14 PM, (19) RE: Easy on the brakes!!!!!, xlspecial261, Jun-17-03, 07:50 PM, (21) RE: Easy on the brakes!!!!!, plainsman, Jun-17-03, 08:41 PM, (24) RE: Easy on the brakes!!!!!, JonN, Jun-17-03, 09:20 PM, (25) RE: Easy on the brakes!!!!!, b101uk, Jun-16-03, 08:43 PM, (13) RE: Easy on the brakes!!!!!, sd70mac666, Jun-17-03, 02:26 PM, (18) RE: Easy on the brakes!!!!!, cyberjim, Jun-17-03, 07:30 PM, (20) RE: Easy on the brakes!!!!!, xlspecial261, Jun-17-03, 07:53 PM, (22) RE: Easy on the brakes!!!!!, cyberjim, Jun-17-03, 11:19 PM, (26) RE: Easy on the brakes!!!!!, xlspecial261, Jun-17-03, 11:24 PM, (27) RE: Easy on the brakes!!!!!, cyberjim, Jun-18-03, 00:38 AM, (28) RE: Easy on the brakes!!!!!, plainsman, Jun-18-03, 01:12 AM, (29) RE: Easy on the brakes!!!!!, xlspecial261, Jun-18-03, 02:14 AM, (31) RE: Easy on the brakes!!!!!, cyberjim, Jun-18-03, 02:41 AM, (33) RE: Easy on the brakes!!!!!, JonN, Jun-18-03, 11:16 AM, (34) RE: Easy on the brakes!!!!!, Vince, Jun-18-03, 06:43 PM, (36) RE: Easy on the brakes!!!!!, JonN, Jun-18-03, 01:31 AM, (30) RE: Easy on the brakes!!!!!, tchouftchouf, Jun-18-03, 02:29 AM, (32) RE: Easy on the brakes!!!!!, shoskins, Jun-18-03, 05:24 PM, (35) RE: Easy on the brakes!!!!!, CharlieB, Jun-19-03, 11:36 PM, (37) RE: Easy on the brakes!!!!!, sd70mac666, Jun-20-03, 11:32 AM, (38)

Conferences | Topics | Previous Topic | Next Topic

What kind of brake physics you got on those cars????
If they are based on Kuju's physics you have empty hoppers applying 150kN of brakes each,.... Not Freaken likely......
Also just because you released the brakes doesn't mean they released... Just like the real world it takes a while for them to come off after an application...... And then you have Kuju's Magic physics engine....
Did I remember to tell you that is screwed?????Chuck Schneider
(Virtual) CEO
North American (Virtual) Locomotive Works

Alert | IP

Printer-friendly page | Edit | Reply | Reply With Quote | Top

I'm not an expert on brakes, or anything else technical, in MSTS, so maybe I'll get shot out of the saddle on this one.Let's do some math here. You have 96 tank cars. For round numbers, let's call it 100 tank cars. You dropped the pressure 1%. For all practical purposes (i.e., assuming no temperature change), that means you released 1% of the volume of brake air in 100 cars. In terms of volume of air, that means you released the equivalent of 100% of the volume of brake air in 1 tank car. How long would it take the compressors on those engines to replenish the entire volume of air in one tank car, if you had just one car in your train and dropped the pressure to zero? And how fast do you think that train would be going at that point? The way I see it, the only thing preventing your 96 car train from coming to a total, rapid halt was the mass of those 96 cars trying to expend "mv-squared" worth of energy in the brake shoes for the time it took those engines to pump the brake system back up to pressure. Just a simple-minded engineer here (the kind that designs things, not the kind that drives trains). Maybe somebody with more knowledge of train brakes will have more to say about it. Charlie

Alert | IP

Printer-friendly page | Edit | Reply | Reply With Quote | Top

Chris,Your first choice for brakes should be the dynamics and only use the air for the final stop, that way you have some control.Derek

Alert | IP

Printer-friendly page | Edit | Reply | Reply With Quote | Top

Dynamics only work up to a point, between oh 15-20mph? BNSF Detector Milepost 666.
No defect
Train Speed 66.6mph
Axle Count: 666
Ambient Temperature 66.6 degrees
outI'm otherwise known as the SatanTrainOh I remember now Dr. Satan. God damn it everyones got to know about Dr. Satan and you know what I'm going to do you a favor, I'm going to let you meet the old geezerIt's all true, the boogie man is real and you found him(Rob Zombie, House of 1000 Corpses)

Soon I discovered that this rock thing was true. Jerry lee Lewis was the Devil, Jesus was an architect previous to his life as a prophet. (Ministry, Jesus Built My Hotrod)

Alert | IP

Printer-friendly page | Edit | Reply | Reply With Quote | Top

>Dynamics only work up to a point, between oh 15-20mph? Where have you been hiding?

Alert | IP

Printer-friendly page | Edit | Reply | Reply With Quote | Top

>>Dynamics only work up to a point, between oh 15-20mph?
>
>Where have you been hiding? Hiding? Here hasn't been hiding!

--You are reading my signature now, don't waste your time reading it!--
Eh, where did my signature go?
Where has my favourite LUL train gone? Maybe it was sent for bolt checking again...

Alert | IP

Printer-friendly page | Edit | Reply | Reply With Quote | Top

>>>Dynamics only work up to a point, between oh 15-20mph? >>Where have you been hiding?
>Hiding? Here hasn't been hiding!oh yes he has a sd40-2 puts out 30000lb @ 45mph and dose 22000lb @ 70mph peking bitween 7mph and 24mph with just short of 60000lb Rheostatic braking force.a sd70mac makes >41000lb @ 45mph and dose 27000lb @ 70mph, peking bitween 4mph and 26mph with just over 80000lb Rheostatic braking force.a dash9 makes 45000lb @ 45mph and dose 22000lb @ 70mph, peking bitween 8mph and 25mph with just over 84000lb Rheostatic braking force.so 8 sd40-2 would put 240000lb of force agenced the direction of travel at 45mph, in my book that is alot more than nothingb101uk

Alert | IP

Printer-friendly page | Edit | Reply | Reply With Quote | Top

No I haven't been hiding just some problems with my ISP that's all I switch to DSL on Wednesday. For those who want the offensive cab photos wait until thenMaybe you aren't on enough
lol
BNSF Detector Milepost 666.
No defect
Train Speed 66.6mph
Axle Count: 666
Ambient Temperature 66.6 degrees
outI'm otherwise known as the SatanTrainOh I remember now Dr. Satan. God damn it everyones got to know about Dr. Satan and you know what I'm going to do you a favor, I'm going to let you meet the old geezerIt's all true, the boogie man is real and you found him(Rob Zombie, House of 1000 Corpses)

Soon I discovered that this rock thing was true. Jerry lee Lewis was the Devil, Jesus was an architect previous to his life as a prophet. (Ministry, Jesus Built My Hotrod)

Alert | IP

Printer-friendly page | Edit | Reply | Reply With Quote | Top

I think this is a little oversimplified. The numbers will vary with gearing, and an SD40-2 can have regular or extended range dynamic braking. The default Sd40 and GP40 do not do a good job at all of modeling the dynamic braking. The braking force drops off much more steeply from a too weak peak, so you will get very little braking action at 45 mph on default files. The work Peter Baker and I did, will enable a much better dynamic braking model, and will accurately model the braking at all speeds.
Bob

Alert | IP

Printer-friendly page | Edit | Reply | Reply With Quote | Top

Sounds to me like the brakes are working better than the Kuju defaults.Empties will stop fairly quickly, once your set propagates through the train. I've ended up stopping short, while stretch braking even, with an empty coal train from 25 MPH in less than 2000 feet.YOu should remember that the brakes should not only take some time to set, but also to release. They don't work like the brakes on your car.From what I have seen fiddling with wag files, to get proper braking you need to adjust the brakeforce based on if the car is loaded or not. Both need to be lower than the default, but surprisingly the loaded cars actually need a slightly lower brake force to mimic the actions of the real thing.There's also a couple other things that can be adjusted to slow down the application and release.Todd

Alert | IP

Printer-friendly page | Edit | Reply | Reply With Quote | Top

Todd
I forget exactly what the command key is but there should be a command for bailing off the brakes and IIRC that's used for undoing the brake ap quicklyGary S

"Some say this country's just out for a fight. After 9/11 man I'd have to say thats right"
"Have You Forgotten"
Darryl Worley

Alert | IP

Printer-friendly page | Edit | Reply | Reply With Quote | Top

Bailing off the brakes only effects the locomotive brakes. Has nothing to do with the train brakes.
btw-I've noticed from various posts in the past that a lot of people are using the locomotive brakes to control their speed. This is a good way to get fired on the real thing.You only use the independant when stopped or very nearly stopped. Never above 10MPH unless you are running light power.Todd

Alert | IP

Printer-friendly page | Edit | Reply | Reply With Quote | Top

>btw-I've noticed from various posts in the past that a lot
>of people are using the locomotive brakes to control their
>speed. This is a good way to get fired on the real thing. Yep. Many railroads don't even allow the use of independents on the main line. -Jeff

Union Pacific is my drug.

Alert | IP

Printer-friendly page | Edit | Reply | Reply With Quote | Top

>btw-I've noticed from various posts in the past that a lot
>of people are using the locomotive brakes to control their
>speed. This is a good way to get fired on the real thing.
>
>You only use the independant when stopped or very nearly
>stopped. Never above 10MPH unless you are running light
>power.
>
Just to add to this, in some places and on some rr's past (and some places in the present I'm told), if you applied any air at all you where then REQUIRED to come to a complete stop and restore the air completely before releasing the brakes. For different reasons, but one obvious is that you want to make sure you had brakes available coming down some long mountain grades when you really needed them, example on the N&W/Virginian, etc., in their coal districts. Long downgrades and too little air pressure is a BAD, BAD thing! Just one example. Lyle

Alert | IP

Printer-friendly page | Edit | Reply | Reply With Quote | Top

>if you applied
>any air at all you where then REQUIRED to come to a complete
>stop and restore the air completely before releasing the
>brakes.How can you restore the air before releasing the brakes Derek

Alert | IP

Printer-friendly page | Edit | Reply | Reply With Quote | Top

true !.. described that incorrectly! still, a complete stop was required before proceeding to restore air pressure to full charge <<== that's how I should have described it >Lyle

Alert | IP

Printer-friendly page | Edit | Reply | Reply With Quote | Top

According to the BNSF Air Brake and Train Handling Manual, for planned slowdowns and stops, you should use a split braking technique...apply the train brakes to reduce the pressure in the brake pipe by 6 - 8 psi, followed by reductions of 2 - 3 psi every thirty seconds or so. For light grades, limit brake reduction to 15 psi, and for mountainous territory (such as the Tehachapi) limit the total reduction to about 18 psi.To avoid running out all the slack in the train, make a final reduction that exhausts all the brake pipe pressure as the train comes to a stop.When using dynamics, you should reduce the dynamic brakes before reaching a grade crossing or diamond, and wait until your locomotive consist is completely across before reapplying the dynamics.You should use a combination of train and dynamic brakes to control (or slow) train speed. When the desired speed has been reached, maintain enough dynamic brake to control the slack in the train until the train brakes are fully released.What Lyle was talking about is a rule in mountainous territory that requires a minimum pressure in the brake pipe before starting down a grade. If the train reaches the summit with less than 80 or 90 psi (depending on the weight of the train), the engineer is required to completely stop and recharge the brake pipe. The correct starting technique in this situation is to set the independent brakes (the locomotive brakes), and the dynamic brakes to full, then release the train brakes and wait for the brake pipe pressure to fully charge and the slack to adjust. Then, reduce the independent brake until the train begins moving. When the whole train is moving, gradually reduce the independent brake to avoid abrupt changes in slack. Once the dynamic brake becomes effective, slowly come off the independent brake all the way.Kurt

Alert | IP

Printer-friendly page | Edit | Reply | Reply With Quote | Top

>From what I have seen fiddling with wag files, to get proper
>braking you need to adjust the brakeforce based on if the
>car is loaded or not. Both need to be lower than the
>default, but surprisingly the loaded cars actually need a
>slightly lower brake force to mimic the actions of the real
>thing.I'm just curious Todd, but what do you set the braking force to in your .wag files? I am trying to get the brakes in my .wags as realistic as possible, but even when I set them to 30kN, they still seem too "heavy" when braking. I don't know if this has anything to do with MSTS's lack of a brake propagation model, but even if it does, the only possible method to simulate propagation in MSTS is to make multiple versions of the same wagon, each with a slightly higher value for the MaxApplicationRate and MaxReleaseRate lines than the previous one. I don't think the extra realism this method would offer is worth the trouble.
Jonathan Nikiforovs.
Milepost 180, CP Belleville Sub.

Repainter for Yonder Locomotive Works.

Alert | IP

Printer-friendly page | Edit | Reply | Reply With Quote | Top

JonN,What I have done is set the maxbrake force on loaded cars at 40kn. These are 143ton cars btw. Lighter loaded cars should have this set lower. Trial and error is about the only way to do it.The thing that has the biggest effect on getting a decent representation or propagation is modifying the maxapplicationrate and the maxrelease rate. I drop these numbers WAY down. Around the 3.5 to 2.5 range. Sometimes as low as 1.5. I have a unit train that I have set up with five different wag files that responds fairly realistically. As you mention, this isn't really practical for loose freight, but works well for trains of the same car.You should also remember that empties do stop pretty quick AFTER the set propagates through the train. For the most part, the cars brakes do not know if the car is loaded or empty (Some do, but I'm not getting into that.) so when you give them a set, say ten pounds, they will always put 25 pounds in the brake cylinder.One thing I haven't gotten around to playing with is the triple valve ratio. Lowering this should reduce the brakeforce for a given set. The 2.5 ratio is the prototypical number, but as the sim doesn't always do things right, I see no reason to leave it alone. Todd

Alert | IP

Printer-friendly page | Edit | Reply | Reply With Quote | Top

Hi Todd and John,
I use a sort of sliding scale for the maxbrake force. My heaviest coal cars are wimpy 116 ton models which I set to 36kN (40kN seems about right for 143 ton version). I just adjust this downward to about 17kN for a 20 ton car. This is not a linear scale, and I realize the cars will mostly have a single brake setting (what Todd was talking about is some cars have a dual (I don't know any with more than 2 positions??) valve such that as the weight of the load presses the body of the car down, the valve is closed and the brake force increased.), but I usually just adjust it dwonward strictly on weight. This seems to give a decent mix of braking throughout the train.
Bob

Alert | IP

Printer-friendly page | Edit | Reply | Reply With Quote | Top

LAST EDITED ON Jun-17-03 AT 09:21 PM (EDT)

Thanks to both of you for the input. I should mention that the specific car that I was using was Okrassa Ghia's 25' GN ore cars (empty version). According to the markings on the side of the car, these weigh 44,000lbs empty, and 160,000lbs full (19.9 and 72.5 metric tonnes respectively). Since 30kN is too high for the empty version, I'll go with 17kN for that, as Bob suggested. I suppose 25kN would be good for the loaded version?Jonathan Nikiforovs.
Milepost 180, CP Belleville Sub.

Repainter for Yonder Locomotive Works.

Alert | IP

Printer-friendly page | Edit | Reply | Reply With Quote | Top

hi"little oversimplified" yes a little but not mutch, there figers were for Real locos, in the defualt suply format with 42" wheels.i supose you could say my 1st reply lacked SpeedCurveExponent so was a bit liner in its aproch b101uk

Alert | IP

Printer-friendly page | Edit | Reply | Reply With Quote | Top

I only use the independent brakes when1. Fully Stopped to shut off the Alerter (provided I have it on), and on those locomotives so equipped with the independent.2. Light engine or light power moves
Everything else I control with the dynamics and the auto brakesBNSF Detector Milepost 666.
No defect
Train Speed 66.6mph
Axle Count: 666
Ambient Temperature 66.6 degrees
outI'm otherwise known as the SatanTrainOh I remember now Dr. Satan. God damn it everyones got to know about Dr. Satan and you know what I'm going to do you a favor, I'm going to let you meet the old geezerIt's all true, the boogie man is real and you found him(Rob Zombie, House of 1000 Corpses)

Soon I discovered that this rock thing was true. Jerry lee Lewis was the Devil, Jesus was an architect previous to his life as a prophet. (Ministry, Jesus Built My Hotrod)

Alert | IP

Printer-friendly page | Edit | Reply | Reply With Quote | Top

Hey Chris, This is how its supposed to work. If you apply the train brake, it drops the air pressure in the air line from lead engine to the rear car and the brake shoes on all engines and cars will stay partially applied until the air line compressor can get line pressure back up to 80 to 85 psi. If you want to slow some without using the train brake, try a little dynamic and engine brakes.
On the SP rescue activity in TP2, I came back down the hill in neutral with engine brakes set at about 50 to 55 percent at 22 mph and could completely stop at 100 percent
The train brake works kinda like in real life. It works off of air pressure, not electricity. So if you apply and then in a second or 2 release the brake, its not going to react to your commands for a few seconds. Thats part of being an engineer. Knowing the limits and reactions of whatever commands you give to it and planning ahead if you can.
Have fun on TP2, I sure am. Jim

Alert | IP

Printer-friendly page | Edit | Reply | Reply With Quote | Top

Actually, the brakes should release once the brake pipe pressure goes up 2 pounds, irregardless of what the set was.And, as mentioned above, if you want to play it like a game, use the engine brakes.If you want to play it as a sim, use your train brakes.Todd

Alert | IP

Printer-friendly page | Edit | Reply | Reply With Quote | Top

Hey Todd, I believe its a little more than 2 pounds, try 20 or 30 on a real engine depending on how much air the resevoir dumped. Also if you have no cars behing you, the train brake is useless, unless train brake and engine brake is combined, which in MSTS is not. Jim

Alert | IP

Printer-friendly page | Edit | Reply | Reply With Quote | Top

Jim,Believe me, I know what I am talking about.
Todd
CP engineer

Alert | IP

Printer-friendly page | Edit | Reply | Reply With Quote | Top

You probably do if you are a real engineer. I just find it hard to believe that 2 pounds can move the brake shoes on each car from full braking position to a released position without the shoes still dragging on each wheel. Now after the resevoir pump builds the pressure back up to 80, 85, 90psi, or however high you have set the limiter at, then the shoes should retract to fully released position.
I was trying to tell Chris that when you dump the air on the train brake that the brakes on the cars won't fully release for about 10 seconds or so. Thats what I've seen for 30 years here in the states. Jim
I'll come up to CP land someday and cap your air behind your first car and see how good your train brake is then. If we didn't have a train brake, railroading would be "very" interesting!! Agreed!! Especially up in the Canadian hills er mountains. Jim

Alert | IP

Printer-friendly page | Edit | Reply | Reply With Quote | Top

Hi Jim,
Todd is in the US part of the CP system, Illinois and Wisconsin I think. I think he is out of Soo and MILW heritage. Just for the record, according to another CP employee, Todd is among their top 3 engineers system wide.
Bob

Alert | IP

Printer-friendly page | Edit | Reply | Reply With Quote | Top

>Hi Jim,
>Todd is in the US part of the CP system, Illinois and
>Wisconsin I think. I think he is out of Soo and MILW
>heritage. Just for the record, according to another CP
>employee, Todd is among their top 3 engineers system wide.
>Bob
I vigorously dispute this statement. I certainly wouldn't put myself in the same catagory as the mountain boys.I do know what I am talking about however. Jim-When you put air into the trainline, you are not pumping off the brakes so to speak, even though that is the terminology.Let's start with a train that has a 90 psi trainline. (The trainline is all pumped up with no leaks. We have no gradient in this trainline to make it simple.) The first thing to remember is that the trainline serves two purposes. It is used to charge the "system", and it is a signal line. Hopefully the following will help explain how this all works.Each car has what is called a control valve, and also two air reservoirs. One is the emergency, and the other is the service. The control valve meters air both to and from these reservoirs.Say you want to set the brakes. You move the automatic handle to the minimum reduction position. This vents 6-7 psi from the trainline. The control valve mounted on each car senses this change in pressure in the trainline. A slide valve inside the control valve moves due to the reduced pressure opening an air passage from the service reservoir to the brake cylinder. Air flows from the service reservoir into the brake cylinder causing the cylinder to apply the brakes through the brake linkage.This slide valve stays open until the pressures in the service reservoir and the trainline are equal. It should be noted that the service reservoir is sized such that you get 2.5 times the pressure of the reduction. ie; A 7 pound set gives you 17.5PSI in the brake cylinder. 10 pounds equals 25 PSI, etc.NOw, lets reverse it and release the brakes. To release the brakes we move the automatic to, surprise, release. (This was sometimes called different things on older brake systems. I'm using the modern stuff for this example.) This allows air to flow into the brake pipe recharging the system. It also releases the brakes, which is a seperate function.The control valves on the cars in the train sense the increase in pressure, using the slide valve again. The increased pressure once again moves the slide valve, but in the opposite direction. This opens two passages. One, to the service reservoir, which allows the reservoir to be recharged. The other vents the pressure in the brake cylinder through the retaining valve.The control valves will sense and react to a two pound change in air pressure. Either up or down. Two pounds up will completely release the brakes. Two pounds down will give you 4.5 pounds more brake cylinder pressure.I should note this is for freight brakes. Most passenger trains use graduated brakes which work differently.This is pretty simplified and doesn't get into the quick release features on modern control valves and such, but it should help.(NOw what I can't believe is I typed all that for a clown that wants to close an angle cock on me.....I'm too nice today.)Todd

Alert | IP

Printer-friendly page | Edit | Reply | Reply With Quote | Top

A clown huh?? I agree that is a very informative reply--thanks--And I know better than to ever not to close an angle-cock mid-train. I have seen some morons do it just to be mean. Alot of guys I would figure are un-aware that there is still air in the car resivoirs even after a car is cut-out by itself, until someone releasess it. I actually won a bet 1 time like this. A friend clained he could push a lone boxcar in a siding. The car was by itself, enpty, doors open, hand brake off, and he couldn't budge it. I walked up mid car, pulled the air release handle and pushed it into place myself. He gave me 20 bucks IIRC.
Down here in the flat south, we have no need for dynamic, except for 1 lone grade up by the red river that I am aware of and another grade east of town that has had alot of coupler breaks over the years, mainly from coal trains getting stopped by the tower downtown. tower would clear them and I'd say 5 times out of 10, the hogger would break the train in half, even though it wasn't really his fault. Kinda amazing the amount of shear that weight can put on a coupler. Some look like they just explode. Jim

Alert | IP

Printer-friendly page | Edit | Reply | Reply With Quote | Top

Many people would be surprised what two pounds of air pressure can do. Here is an example. It only takes about a half pound of overpressure (amt. of greater pressure on one side than the other) to shatter most glass windows. When you think about it, air is heavy stuff. Since earths atmosphere has an average pressure of about 15psi, a person would be subjected to several tons of pressure every day. Jonathan Nikiforovs.
Milepost 180, CP Belleville Sub.

Repainter for Yonder Locomotive Works.

Alert | IP

Printer-friendly page | Edit | Reply | Reply With Quote | Top

May I respecfully suggest you all (not you Todd, you already know this) read this essay How RR Air Brakes Work Part 1 and 2 at Al Krugs website;http://www.vcn.com/~alkrug/rrfacts/rrfacts.htmIt is a detailed description on the many questions all of you have been asking.Re: The issue of why couplers break is also discussed here in Drawbar Limits.This site should be required reading for anyone desiring to operate the Sim in a prototypical manner. Thanks Al.

Regards,
Vince Cockeram
NEC Track Team
Author of the NECv4 Route
E-Mail me at vcockeram@lvcm.com

Alert | IP

Printer-friendly page | Edit | Reply | Reply With Quote | Top

LAST EDITED ON Jun-18-03 AT 01:39 AM (EDT)

>unless train brake and engine brake is combined, which in MSTS
>is not. JimJim, I have found that actually depends on which locomotive you're driving. If they are combined and you start an activity with a lone locomotive on a hill, the loco will not move. If the brakes are not combined, then your engine will immediately start rolling. This is controlled in the brakes controller section of the .eng file, but I'm not sure exactly what to change to combine or "uncombine" the independant brake from the train brake. I'll have to do some experimenting.
Jonathan Nikiforovs.
Milepost 180, CP Belleville Sub.

Repainter for Yonder Locomotive Works.

Alert | IP

Printer-friendly page | Edit | Reply | Reply With Quote | Top

According to AAR, for a four axle wagon: Loaded Net Braking ratio
TOFC/COFC
- Mimi (maxi loaded mass)x0.44
- Maxi (maxi loaded mass)x0.52
All others
- Mimi (maxi loaded mass)x0.34
- Maxi (maxi loaded mass)x0.52 Maximum Empty Braking Ratio
- (empty mass)x1.52 Minimum Hand Braking Ratio
- (maxi loaded mass)x0.4 Try this:
http://www.standardsteel.com/rdpapers/freightcar.pdf
and
http://www.thelink2.com/air_brakes_101.htm JLC

Alert | IP

Printer-friendly page | Edit | Reply | Reply With Quote | Top

Hate to say it, but that's the way it is on a real freight train too...you just have to know when to bail off the brakes.Reason is, you let out a little bit of air from a long train -- and the compressors in the locos take quite some time, relatively, to build up the brakes to release them. Remember, that train brakes release with air being replenished -- you lose your air, they lock up (i.e. Big Hole.....emergency application).

Alert | IP

Printer-friendly page | Edit | Reply | Reply With Quote | Top

Jeez...nothing against you, shoskins...but that's what I said way back on 6/16 in the second reply to this thread. Has anyone heard from SVTS in all of this? Have we answered the original question? Man, I've learned a lot about train brakes and about how MSTS simulates them. I'm glad we got into it, but jeez all SVTS wanted to know was why the train didn't respond the way it was expected, and that boils down to the response time of the brake system. BTW all of this has been focused on modern diesel engines and cars. I'm pretty much working in the steam era. Any differences?Charlie
Old Colony-Newport Branch
Newport, RI

Alert | IP

Printer-friendly page | Edit | Reply | Reply With Quote | Top

All this for brakes?
All this for 2 pounds of air?All this for a good discussion
BNSF Detector Milepost 666.
No defect
Train Speed 66.6mph
Axle Count: 666
Ambient Temperature 66.6 degrees
outI'm otherwise known as the SatanTrainOh I remember now Dr. Satan. God damn it everyones got to know about Dr. Satan and you know what I'm going to do you a favor, I'm going to let you meet the old geezerIt's all true, the boogie man is real and you found him(Rob Zombie, House of 1000 Corpses)

Soon I discovered that this rock thing was true. Jerry lee Lewis was the Devil, Jesus was an architect previous to his life as a prophet. (Ministry, Jesus Built My Hotrod)

Alert | IP

[ Home | MSTS Forum | MSTS FAQ | File Library ] Copyright © 2002 by Nels Anderson. All Rights Reserved.