Big Boy and Challenger Turntable

[dick8299]

I have been working on a turntable big enough to handle the Big Boy and Challenger engines, and have one just about finished. The engine and tender fit on the turntable (it is 44 meters long) and will turn one track at a time. However, I guess due to the multiple component construction of the engine, it is too unstable to overcome the turntable wobble issue if you try to rotate more than one track at a time, and the scenario ends due to derailment.



Like I said the model is almost done, the beta picture above pointed out some modeling errors I need to correct, but that is a small matter. The question is, should I pursue this further or just drop it due to the engine stability issue? There are connection points on the turntable for 48 tracks. If the route builder wanted to take the time to add a track at all 48 locations, then you could turn the Big Boy engine one track at a time and probably be successful. Otherwise, the engine will tilt off if you try to skip a track.

[dick8299]

I had a thought after I made the previous post, that there may be a way to slow down the animation to a crawl, and overcome the wobble issue. I will try that, and report back.

[johnmckenzie]

Looking good!

[dick8299]

I use 3 DC 7.1.2 and set the animation to 360 keys at 1 key per second, which should have slowed down the animation by a factor of 10 from my previous attempt. But the animation went the same speed when I rotated the turntable in RW3, and did not slow down. The result was that the Big Boy wobbled off of the track.

I am open to suggestions on how to overcome the turntable 'wobble' phenomenon.

[Machinist]

AFAIR in Trainz we have to give a command for each node of turntable (your idea of adding more nodes and raising the speed per key would work in this case), but in RW each keypress (g or shift+g) will result in the turntable moving directly to the next connected track, skipping all other tracks. Maybe it makes the turntable go faster till be close to the desired track. And then I ask you: even moving to an adjacent track (I mean just one node to align) it moves fast enough to derail the engine?

It may seem a silly suggestion, but there are so much weird behaviors in the codes, that I ask you also (though I'm quite sure you already did that): did you try to reduce the tracks (the keys) to a lower number and/or increase the speed to (say) 5 seconds per key?

Cheers,
Lisboa.

[dick8299]

. And then I ask you: even moving to an adjacent track (I mean just one node to align) it moves fast enough to derail the engine?

Cheers,
Lisboa.

If the route creator places a track at each exit of the turntable, and presses the g key to move to the next track (one at a time), the engine does not derail. It only derails from going past empty (no track installed) exit points, or if you press the g key quickly, not allowing the engine to stabilize at each exit point.

[Machinist]

. And then I ask you: even moving to an adjacent track (I mean just one node to align) it moves fast enough to derail the engine?

If the route creator places a track at each exit of the turntable, and presses the g key to move to the next track (one at a time), the engine does not derail. It only derails from going past empty (no track installed) exit points, or if you press the g key quickly, not allowing the engine to stabilize at each exit point.

Humm... then it is varying from route to route (or asset) because in Bath Green Park route, standart scenario "Bruised and Battered", the turntable goes directly to the connected track, overpassing another existing exit beside, with one single keypress (g). See and check, is easier than I try to explain what I mean...

[dick8299]

It goes to the directly connected track when first aligning with the lead track that the locomotive is on. I am talking about how the turntable behaves when the locomotive is on the turntable. Each g press turns the locomotive to the next installed track, bypassing empty (no track) locations.

[XDriver]

I'm glad to see your making this.
I can't help with your problem, but I know it's frustrating. I'm looking foreword to this addition when you get the bugs worked out. Now we'll have to make a new route to include the Cheyenne shops where the 3000's and 4000's lived. Now that would be some work.
How many tracks did you say?

[Machinist]

It goes to the directly connected track when first aligning with the lead track that the locomotive is on. I am talking about how the turntable behaves when the locomotive is on the turntable. Each g press turns the locomotive to the next installed track, bypassing empty (no track) locations.

I never played a scenario in which I was rotating on a turntable, I thought the behavior was the same. But I have to confess that the cab sway whilst spinning is amazing especially when engine is about to derail.

It looks like a hardcoded issue, according to Adam (RSC?):
http://forums.uktrainsim.com/viewtopic. ... d&start=38

In this case the invisible tracks idea (from mdurdan) may be the last attempt...

[Machinist]

There are connection points on the turntable for 48 tracks. If the route builder wanted to take the time to add a track at all 48 locations...

And yep! you should finish your work creating some versions with reduced and different number of locations... and then make it more flexible and easier to route builders.

[dick8299]

Machinist, that is the way turntables are made - the route creator places tracks at which turntable exit point he wants to, a track is not required at every exit point.

Anyway, there may be a way to improve the engine's inherent stability. I have tested mine and got improved performance. I am asking Mike Durdan to try my potential fix on his installation to see what happens.

[Shayfan1]

Great package that baby up! We got some big iron that needs turning

[Machinist]

Even better news yet, I was told a possible reason why locomotives wobble on the turn table and I will be personaly working on a fix for each and every locomotive if I can make one succuessfull fix for the wobble problem

Great! Once the wobble issue exists since RS/RW2, is not related to cab sway, right? If you fix or reduce the wobble, will it reduce the cab sway?

[dick8299]

Well, as far as I am concerned the Big Boy Turntable is finished. M Durdan, the beta tester, was smart enough to contact IHH and learn that IHH no longer owned the Big Boy but had sold it to RSC. Therefore it is OK for me to upload a Big Boy clone bin file with the Turntable as a repaint. The clone has the EaseOfDerailment set to zero which makes the engine more robust and less likely to derail when turning on the turntable. It will however still be liable to derailing occasionally, and I will put a caution in the read me file to save the scenario prior to loading the Big Boy onto the turntable. All that is left, is for me to create the readme file, and get the package set up. It should be available in the library in a couple of days.

Again, thanks to Mike for checking out the beta copy, and for getting the info from IHH.