There are some but the cog can not be made to work in Trainz.
Well I'd rather say it's more like - we can create an illusion that appears to mostly work now. While it isn't likely we can sync the loco's cog gear exactly to the rack teeth as it moves it is possible to change the wheelslip effects in Trainz to almost eliminate any lost motion. This goes a long way in providing the illusion that the cog is engaged and not slipping on the grade.
Still not much in the way of rack stuff though, as I found when I did that Tasmanian route a couple of years ago.
In terms of physics, it would have to be a bit of a party trick in that the motive power would simply have enough horsepower and adhesion value not to get overpowered on a 20% (1 in 5) slope (or you run in DCC). But there are many rack railways crying out to be represented, not just Switzerland but places like Czechoslovakia (Tanvald) and part of the old Yugoslavian narrow gauge also relied on rack sections to get trains over the hills.
It is not that much of a trick Vern. I did a couple of especs for Peter's little Abt rack loco. I don't know how typical they are of rack locos but they had 2 separate drive systems - one for adhesive track and the other when on the rack. 2 sets of cylinders, 2 sets of controls and 2 different rated TEs. In addition from the info I found they could and did sometimes use both drive systems when on the rack.
Getting the TE right is just a matter of testing. PLEASE NOTE: the CONTINUED LACK of support for STEAM locos on the "TEST TRACK" feature in TANE and TRS19. This is just ridiculous. What's it been 5 years or 6 since it was introduced. I can't express my displeasure and astonishment at the lack of support and improvement for steam physics by N3V. All eye candy and no substance comes to mind even if that isn't fully justified. Why can't they test STEAM locos on the in-game TEST TRACK - they designed it, they coded it and then they prohibited any testing of steam locos on it. As part of the TEG group when this was being developed N3V lead me to believe that I would be able to test steam locos on this new feature in TANE. I'm still waiting for this final missing part to be addressed.
You can get TE just about right by creating an espec for any steam loco using the actual characteristics and dimensions and then reduce most by 40% in the final espec. The resulting TEs are close to actual rated when tested in the game. It's a shame it doesn't work like this in the real world - I get the same power out of a drive system that's 60% the size of the real one - steam might still be King. I'll also point out that in Trainz the TE of steam locos going in reverse - from actual tests in the game - is roughly 60% of their forward TE's. It does beg a few questions. I've sent in my 8x10 glossies and reports with figures but I haven't seen any fixes, corrections or improvements in the game yet.
Within the current state of the game engine as noted I don't believe it is possible to sync gear and rack teeth as the loco moves. Something might be possible in scripting but that's probably more cpu intensive than the steam loco cuff systems that they stated weren't the intended use of scripting system.
As a final note, I've suppressed the wheelslip on the drive wheels on steam locos while running tests of locos on the rack to create not only the illusion of engaging the cog but mainly to reduce any problems that lost motion would inject into the tests. And this can be done easily either thru the Vehicle Physics Rule or custom scripting. I've used custom scripting that uses a kind of "manual" switching of these parameters during the tests. The script is set to use some odd whistle signals to trigger it in keeping with the steam loco era I like to model.
In any case this could be controlled in the game by triggers marking the end points of the rack and scripts responding to the triggers and determining the direction of travel. So on the rack the wheels don't or at least rarely slip and off the rack they slip normally. You could even swap out the espec (since TANE) in the Driver Module to reflect the different drive systems in use at any time (like the loco I mentioned above) but that probably would have some problems since I think boiler settings are reset when this is done. But it might be done under the right set of circumstances/restrictions.
You can check for info on the Vehicle Physics Rule -
here.
Bob Pearson
PS @Javier many thanks for that link. I dl'd the track and will take a look.
