SD70 Sherman Hill Wheelslip Error

[buzz456]

Or go find another locomotive to run for a bit.

[mrennie]

The default wheelslip physics calculations in the core code are fundamentally wrong anyway, regardless of what values you put in the blueprints. At present, the only way to get realistic wheelslip physics is to override the core code with LUA scripting for each individual locomotive (which is what I did for the GTEL and my own steam locos). You can fiddle with the blueprint values to make the default wheelslip less unrealistic, but it'll never be right.

[Ericmopar]

I just modify my traction coefficients in the blueprints. It works fine without scripting. There are separate limits for dry, ice and rain if I remember right.
They are wrong on some locos in a big way. I've had trains start slipping when going under 20mpg in notch 5, when I've seen the same type of loco like a Dash-9, crawling up Donner or Tehachapi in notch 7 or 8 with no sand at 10 mph.
Like said above, some have terrible high speed slippage as well.
I read an article on sand usage, and learned it isn't much help at all. In fact it's no help at all on dry rail, only when there is moisture or contaminants on the railhead.
In the real world if you are slipping on clean, dry rail, at 10-15 mph, and the train is being handled normally, then you just plain don't have enough power on it.

It's funny this should come up. I had forgotten that Donner's Dash 9 are way to slippery when I made my last scenario, and have been wondering if people are needing to sand all the way up with the OEM traction settings. Mine are modified so I can get down to 10 mph without sanding.

@SD40Australia.
This is why many of us turn scoring off in game and modify the physics. We can fix stuff but the game/sim don't like that when playing Career Scenarios.
I did a clean install and forgot to reinstall my backup a few months ago, and got a very rude reminder of how unpleasant this sim is without all the physics, coupler, brake fixes installed.

I do have a Donner Pass physics,brake fix in the file library, but I can't remember if it includes the traction fix for the Dash 9. I keep thinking that traction issue is something that was broken in one of the yearly updates, like the Challenger not remembering it's front engine half after a scenario save, or it's cylinder cocs for that matter.
Or the tunnel lighting on Marias. Those tunnels used to be one of the reasons I loved that route, now they're banded like a Zebra.
That breaking things that worked in the past and loved, is why I'm hesitant to by new DLC from them now.

[BNSFdude]

It doesn't help that Dovetail doesn't know the right weights. While developing the pack, I was correcting the weights of locomotives all the time.
I alleviated most slip issues with our GEVO enhancement pack. Like Mike, it is reliant on heavy scripting.

[Ericmopar]

The stuff you're looking to modify is in the engine's simulation.bin. A good starting point is .90 for the dry traction, .85 for wet, and .80 for snow/ice.
Some DLC may have a different simulation.bin for each engine, some may use a folder named Default and will have one simulation bin for all paint versions.

Mike's RW_Tools is now free and it's perfect for this. When you get done making a change, go to "File" and select "save". It will automatically make a backup in case of total disaster.

[mrennie]

If you really want to eliminate wheelslip, the easiest way is to change the friction coefficients in the simulation bin file to something ridiculous such as 100. That's what I recommend, given that you can't get realistic wheelslip no matter what values you put in the bin file.

[Ericmopar]

If you really want to eliminate wheelslip, the easiest way is to change the friction coefficients in the simulation bin file to something ridiculous such as 100. That's what I recommend, given that you can't get realistic wheelslip no matter what values you put in the bin file.

It doesn't have to be 100 Mike just 1 in this particular case.

[mrennie]

If you really want to eliminate wheelslip, the easiest way is to change the friction coefficients in the simulation bin file to something ridiculous such as 100. That's what I recommend, given that you can't get realistic wheelslip no matter what values you put in the bin file.

It doesn't have to be 100 Mike just 1 in this particular case.

Yep, but I put 100, or 1000, to make absolutely sure

[Ericmopar]

Those numbers are still wrong as there is no way sand adds 12 times traction. I figured out the numbers some time ago except for Horsepower.
It turns out the guys that have said that HP is actually KW are right. One of the guys here did some number crunching recently and figured out the Kilowatt thing.
Studies show sand only gives about a .10 traction increase and that's when it's wet rail. On dry rail there is almost no help. IE the sand multiplier shouldn't be more than 1.10 although I fudge it to 1.15 .
It's funny. whoever created the game engine for this sim knew what they were doing, but the numbers keep getting entered wrong.

The coupler settings are all there for both Amerincan and European coupling systems, but almost no one knows the correct numbers for that either.
People do all kinds of complicated scripting etc, when most of these things are already in the .bins .
Minimum Distance .01 (Keeps them from pushing in and correct distance)
Maximum Distance .05 (Keeps them from pulling out too far and also correct distance) (I use .03 on passenger stock)
The minimum and maximum distance settings also allow for realistic slack.
Target Distance 0 (Lets American Couplers float in the pocket like real ones) (Probably applies to buffer couplers centering from spring pressure)
Damping 0 (American couplers don't have shock absorbers although this setting probably also applies to buffers.) (If a person is a bad driver, they can set this to about 600 to offset crashing into cars when coupling LOL)

Even when I give people these numbers they always tamper with the values. Like setting minimum distance to 0 which turns it completely off in this case and lets the coupler push into the car body, causing a consist tilt and/or collision error.

[BNSFdude]

(American couplers don't have shock absorbers although this setting probably also applies to buffers.) (If a person is a bad driver, they can set this to about 600 to offset crashing into cars when coupling LOL)

Yes they do, actually.
Lumber Flats, a large amount of box cars, auto racks, and most flat cars have End of Car Cushioning, which adds about 3 feet of play on each end of the car depending on what kind of car it is. It makes running trains a real pain in the butt.

[Ericmopar]

(American couplers don't have shock absorbers although this setting probably also applies to buffers.) (If a person is a bad driver, they can set this to about 600 to offset crashing into cars when coupling LOL)

Yes they do, actually.
Lumber Flats, a large amount of box cars, auto racks, and most flat cars have End of Car Cushioning, which adds about 3 feet of play on each end of the car depending on what kind of car it is. It makes running trains a real pain in the butt.

I agree but was talking "in general"
If I remember correctly, I added some damping to Larry's PFE mechanical reefers because they have a cushioning system. I don't know how it's done now, but the couplers themselves are/where actually mounted the same way as usual in a pocket, with about 6" slack per coupler, but there was a beam that ran from draft gear to draft gear below the car, and that beam in turn was allowed to slide in a pocket roughly the length of the car, with a damping mechanism near the center of the car's chassis, hooked up between the sliding beam and the rigid part of the car's framework.

[BNSFdude]

Not all draft gear has Springs in them. Only cars I've stated above as examples are typically found with cushioning.

[Chacal]

@SD40Australia: If you start working seriously with RW settings, you'll need to setup RW-Tools as the default program for opening .xml, .bin, .proxyxml and .proxybin files.
This way, you just double-click on a .bin file and RW-Tools will convert it to xml and open it in its internal editor. You can then modify it, and when you save it RW-Tools will convert it back to a .bin (using serz.exe internally).
.dcsv files are just xml files with a different extension so you can open them in a text editor.

For heavy editing in text files (such as xml files), I recommend an advanced text editor like Notepad++. This will, for example, highlight xml tags with different colors, making it much easier to work with. You can make your editor the default program for opening .xml, .proxyxml and .dcsv files.
For example, what I do for complex editing of a .bin file:
- Double-click for opening the file in RW-Tools;
- Copy and paste the whole text in Notepad++
- Edit
- Copy and paste the whole text back in RW-Tools;
- Save

There are lots of other advantages for using RW-Tools and advanced editors, of course.