Big Boy Pulling Power

[bpetit]

It feels really sluggish to me, only doing 40 or so on dead level track.

Availabe here: viewtopic.php?f=30&t=5635

[arizonachris]

What route and what scenario? Depends a lot on what consist you are hauling. I've had the Big Boy way over the speed limit on B-SB route, probably about 60 or 70MPH, but pulling a string of empties. If you're getting 40 with that Sherman tank scenario, that's twice what I ever got.

[XDriver]

Someone needs to modify this thing. I did some myself but I didn't improve on the power just faster water feed and coal feed. Somewhere back in the topics there was a person who did mod this thing but I can't remember who.
You watch some of the Big boy documentaries and it says one BB could pull a 5 mile long train on level track. IHH BB? I don't think so. If I was sure of what to look for I would do it myself. I know it's in the simulation bin. Not sure on what portion. I have smoke, sounds, texture and whistle stuff like that modded. Would like to get the power up tho.

[bpetit]

Found it! viewtopic.php?f=6&t=4459

_o_OOOO_oo-Kanawha seems to have modified based on the allegheny engine's performance on the C&O.

[JackD]

Found it! viewtopic.php?f=6&t=4459

Thanks for finding this!

[bpetit]

No problem Though I am looking around the files trying find a maxhp or something.

[bpetit]

Tests, Tests, Tests.
Running Bigboy up Cajon Pass South Track, which is a 3% grade.

Test #1
One Bigboy and 20 coal cars on a 1.9% starting grade running with 100 percent regulator and 80% cutoff doing 15mph and increasing. As soon as I hit the 3% grade, I had to put 95% cutoff with the speed at 12mph it also increased bit by bit got over the pass.

Test #2
Two Bigboys and 60 coal cars on the starting grade, I had to use full regulator and cutoff plus the sander to get started. Currently at 18mph going up a 2.7% about to hit the 3% grade. I hit the 3% grade and well I encountered a little wheelslip here and there but the water level was .65 so I had to stop on a 2% grade. Finally after the water level played catch-up I was able to start moving again. Two Bigboys can make it over the pass with 60 coal cars.

xDriver, can you tell me what you changed to make the water and coal levels go faster?

[XDriver]

I'm thinking it was here for coal stoker. This is in the BB_Simulation.bin.
I'm really not sure if these are it or not. I forgot what I did. Sorry.

Code: Select all

                           <MinStokingRate d:type="sFloat32" d:alt_encoding="0000000000000000" d:precision="string">0</MinStokingRate>
                           <MaxStokingRate d:type="sFloat32" d:alt_encoding="000000000088C340" d:precision="string">10000

As far as the water injector. It's somewhere in here. I can't remember what I changed. Compare these values with the default.
If you're making a better BB, please share your results when your done.
I do know the reason I did these was because of what you said. Stopping because your running out of water is not a good thing.

Code: Select all

<MinInjectorProportion d:type="sFloat32" d:alt_encoding="000000000000D03F" d:precision="string">0.25</MinInjectorProportion>
                           <MaxInjectorProportion d:type="sFloat32" d:alt_encoding="000000000000F03F" d:precision="string">1</MaxInjectorProportion>
                           <Size d:type="sUInt32">11</Size>
                           <FeedRateMulitplier d:type="sFloat32" d:alt_encoding="000000606666EE3F" d:precision="string">0.95</FeedRateMulitplier>
                           <PrimingFailureLevel d:type="sFloat32" d:alt_encoding="000000000000F43F" d:precision="string">1.25</PrimingFailureLevel>
                           <SteamUsageMultiplier d:type="sFloat32" d:alt_encoding="000000A099991B40" d:precision="string">6.9</SteamUsageMultiplier>
                        </EngineSimulation-cSteamInjectorBlueprint>
                        <EngineSimulation-cSteamInjectorBlueprint d:id="43703848">
                           <Type d:type="cDeltaString">eExhaust</Type>
                           <MinBoilerPressure d:type="sFloat32" d:alt_encoding="0000000000004E40" d:precision="string">60</MinBoilerPressure>
                           <MinInjectorProportion d:type="sFloat32" d:alt_encoding="000000A09999C93F" d:precision="string">0.2</MinInjectorProportion>
                           <MaxInjectorProportion d:type="sFloat32" d:alt_encoding="000000000000F03F" d:precision="string">1</MaxInjectorProportion>
                           <Size d:type="sUInt32">15</Size>
                           <FeedRateMulitplier d:type="sFloat32" d:alt_encoding="000000606666F23F" d:precision="string">1.15</FeedRateMulitplier>
                           <PrimingFailureLevel d:type="sFloat32" d:alt_encoding="000000000000F43F" d:precision="string">1.25</PrimingFailureLevel>


[_o_OOOO_oo-Kanawha]

I am still tinkering away at the IHH Union Pacific Big Boy in order to simulate an C&O Allegheny. The MSTS model of which is still sitting on my erection floor waiting to be converted to TS2012.

It is my impression that the current steam simulation engine inside TS2012 is not suited to big articulated US steam locomotives. The Big Boy, like the Challenger, is modeled as two engines in one, the "front frame" and the main rear frame that carries the boiler and firebox. I have the impression it is running in double header mode by default and you are driving and controlling the rear engine. In manual firing mode I keep running out of water no matter how I operate the injectors. The F5 display shows me handling the controls completely different compared to the ControlStateDialog window. The F5 displays shows a boiler full of water, me handling the firedoor and stoker and injectors in correct fashion, but the ControlStateDialog shows a steadily decreasing water level until the engine eventually stops due to lack of water. In automatic fireman mode it seems both "engines" are slaved to each other and the stoker and injector operates automatically with no lack of water or coal. The injectors are a whole story in themselves, as most large and modern US steam power had a completely different cold water feed compared to the typical "small" UK steamer. Manipulating the values sort of gave me a centrifugal pump with high output and low steam consumption for I assume the fireman's boiler feed would be sufficient to keep a full glass of water no matter the load. The engineer's live steam injector is generally only used to feed cold water into the boiler to keep the valves from popping when suddenly going into emergency or when the fire has been built up but departure is delayed. You wouldn't want to be near a 300 psi pop off for the sound is an ear splitting roar that will frighten most casual bystanders.

I wanted the Big Boy to be more alive and realistic in manual mode, so I added all kinds of smoke and steam emitters to the compressor, live steam injector, cold water centrifugal pump, exhaust injector and stoker engine. I also want towering columns of steam when I fully open the blower, or when the big safety valve pops. Likewise the cylinder c-o-c-k-s (this is a legitimate term yet gets word filtered ), they should emit a whisp of steam when the throttle is cracked open just a little, but should emit billowing clouds of steam when accelerating away. None of my manual emitters yet seem to work in automatic fireman mode. Perhaps the other simulation file also needs to be hacked, the one that controls the AI Big Boy?
I also tried two dynamic smoke stacks, but ultimately failed. Since the simulation model allows only one "puffing"and "chuffing" stack and my efforts to have both the front and rear engines their own, separate smoke stacks that respond to wheel slip individually were fruitless I took a different approach. I again gave the Big Boy two smoke stacks and have both respond to throttle and stoker, more throttle means more white steam, more stoking means more black smoke. I wanted the black smoke to rise and fall according to speed and back pressure but was unable to control the emitters that way. Controlling TS2012 emitters is like the darkest of dark magic, there are only two parameters that can be scipted and emitter velocity isn't amongst them I think.
Switching between different "column height" emitters also didn't work like I wanted so I finally settled on mixture of white steam that sort of blasts but doesn't drift combined with black smoke that slowly billows and drifts backwards over the train. I really hate that balloon effect so I am satisfied with my exhaust so far as it leaves a nice long trail that slowly falls down over the cars. I still plan to try some sort of rotation synchronized one-shot "blasting" emitters to simulate those heavy chuffs when accelerating away under full load.

There are several essential features not implemented by the TS2012: wheel slip and popping safety valves. I am still experimenting to get some sort of prototype reacton to these events as in some of the more recent UK steam engines there seems to be some kind of effect.

The sound emitter is already overloaded at speed as it is, so adding a separate sound emitter to the "front frame" only made matters worse. Only at slow speed one could sometimes hear the two engines chuffing asynchronously but the effect quickly vanishes at speed. It is a pity the whistle isn't quillable, perhaps an analogue control value combined with more sample loops will make this possible?

Sanders finally, the Allegheny which I try to emulate had huge sandboxes and was capable of continuous sanding the whole of the 50 miles ascent between Hinton and Alleghany, Va. station. So I want to emulate clouds of yellowish-grey dust coming off the wheels close to the rails. Controlling the density and length of the clouds with the forwards speed so far proved dissatisfactory.

So all in all I am less than pleased with the Big Boy, it just won't behave as I want and come to life as a really big steam locomotive. Perhaps I want too much but I'll keep tring and perhaps eventually will release my hack. I lost the operating cab along the way, but since the cab is awkward, with the gauges and waterglasses hardly visible in the dark I don't care much about it. I have an engineer and fireman in the cab and a nice projecting headlight as compensation.

Finally, regarding power, a Big Boy is no more powerful than an ES44, despite being much more locomotive so don't expect miracles from it. It would take 4 of them to pull away that 110 car 14000 tons train against the sharpest curves and ruling grade between Harts Run and Tuckahoe in one of Tori's COARW scenarios.

[JackD]

_o_OOOO_oo-Kanawha,

Thanks for updating us on your efforts to improve the BB. This is too great a loco not to be able to drive it realistically.

[bpetit]

I'm also modifing the BigBoy's Power and Tractive Effort and Speed. Sssshsh its a secret. Here's the thing though if you operate the regulator above 50% you lose the water level so 49% regulator and below actually lets it fill up so to speak. I'm just trying to get it a bit better than the stock one.

[_o_OOOO_oo-Kanawha]

Yes, I noticed that too, the steam production vs the steam consumption curves don't match up. I again assume the TS2012 physics model is to blame, there are lots of variables but the equasion which evaluates them is unknown, so it is just guesswork and trial end error. Like with prototype steam locomotives and like IHH states in the documentation.
My main problems are with the manual operation, which is the most realistic, interesting and fun way to drive a steam locomotive.

Steam production should be controllable by firing and injecting alone, I don't know if big US steam locomotives used dampers as their fireboxes are completely above the frame and the ash pans are only shallow. Steam consumption is of course load and speed dependent and should be controllable by regulator and cut-off, one should be able to match consumption to production.
Here lies one of the main differences between the UP Big Boy and the C&O Allegheny, the Allegheny has the more powerful boiler and burned better coal so it had the higher power sustaining capacity.
I recently acquired the book "The Allegheny, Lima's Finest" but haven't thoroughly perused it yet. It seems to me the UP Big Boy is the better documented engine still, but I have no books on it in my possession.

[arizonachris]

You always have to fiddle with the regulator and reverser. I look at steam usage and steam production, like Kanawha said. With the Big Boy, top speed for me is usually about 23% reverser and 35 to 38% regulator. Every other steam locomotive is different. I really don't know which is my favorite, and I think I have them all for RW. I can make the Scotsman fly, as well as the Tornado. And the GS4's are a dream.

The C&O Allegheny is difficult because Tori designed it that way. Good thing the Big Boy has unlimited sand!

[bpetit]

Upgrade maybe tomorrow? Anyway here is a list of the changes I have made.

-Horsepower and Tractive Effort to almost real life values
-Water in Tender to 22000 gals instead of 15000 gals
-Weight increase on front frames and back frames
-Dry Wet and Snow Traction Values Changed.
-Speed Increased( you can do 80mph now >:D)