1218 coming along - articulation advise requested

[nw_fan]

My plan is to build two locos:

1. 1st eng in consist - boiler and rear drivers/trailing truck along with light effects (This is the one you drive in MSTS)

2. 2nd eng in consist - front drivers/lead truck/pilot (actually run in front of driveable loco in MSTS)

The problem I forsee is the rear drivers will slip and the front drivers will not because they are an AI loco. Is this thinking correct? Do AI locos slip their drivers? In real life, the front drivers on an articulated (with the cab in the rear) slips only it's front drivers as I understand it. So my model would work in reverse of reality. Unless the ENG file is set up so that the rear drivers (drivable loco) never slip either. Then no drivers would slip. Better than the wrong ones slipping, I guess. Any thoughts on this?

BTW, here is a progress shot. I have gotten a few offers for help from various people from the Forums and am very appreciative of the help I have received already. I will need some ENG file help still, though (still quite a ways in the future)

http://forums.flightsim.com/dcforum/User_files/3d0451f451e03f38.jpg

Thanks,
Mike


http://forums.flightsim.com/dcforum/User_files/3beb2a23059f2cb2.jpg
Norfolk & Western
Precision Transportation

[Adam3291]

LAST EDITED ON Jun-10-02 AT 07:06AM (EDT)[p]Looking good Mike. When you going to start with the siderods and valve gear. Sorry about that E-Mail promblem. I did get your E-Mail I just didn't get to see it til yesterday. My brother is at fault on this one. See we have 3 computers in my house and they are all on a network. So if you check E-Mail on the wrong computer it will go to that computer. So meaning my brother checked E-Mail on the wrong computer. Sorry

http://forums.flightsim.com/dcforum/User_files/3d00d3b955440ab5.jpg
Adam Parsons
stparsons@lexcominc.net

Your promblem with the back engine slipping is correct. If you use two engine files that will happen. So when you start a train put the throttle up slowly so you get it moving with no slipping.
When I tested Jens Big Boy that happened only with the throttle was pulled up too fast.

[pwillard]

heheh.... And you think they didn't have that problem with the prototype?

http://forums.flightsim.com/dcforum/User_files/3d0125ea4bd60b54.gif
Pete Willard

[mikkox]

>1. 1st eng in consist -
>boiler and rear drivers/trailing truck
>along with light effects (This
>is the one you drive
>in MSTS)
>
>2. 2nd eng in consist -
>front drivers/lead truck/pilot (actually run
>in front of driveable loco
>in MSTS)

If you do like that, the lights, smoke effects and the cabview will turn with the 2nd unit, the the front drivers. That is bad. But there is a way around it, you'll just lose a turning front truck, unless you add a wagon, representing the front truck. You have to set the bogie pivot points for the both units at the same place so they turn the same amount in curves. And make the unit with the front drivers a bogie. The main body of the second unit will turn with the 1st unit.

>correct? Do AI locos
>slip their drivers? In

Yeah, but not as easily as player loco. You just have to tune the weight (you have to decide how you divide the weight of the whole locomotive to the two eng-files) to get the front drivers slip right. And maybe adjust the adheasion parameters.

[Emmo213]

Why would the cabview and smoke follow the second units movements? If the front drivers are technically behind the loco, then the sim would still use the rear set as the front. That's confusing so let me try it a different way. One loco is the boiler, cab and rear set of drivers. This would be the first loco in a consist. The second loco in the consist would be front drivers. Now according to MSTS they are behind the lead loco, but maybe with a bounding box or something they appear to be infront where they would normally go. I don't know if that's possible but it kinda makes sense.

Brian :-)

[mikkox]

>drivers. Now according to MSTS
>they are behind the lead
>loco, but maybe with a

Yeah, but the problem is that the couplers are defined by the Main pivot point and the lenght parameter in the eng-file. If you put the unit with the front drivers behind the unit with the rear drivers, there's no way you are gonna get the front drivers to turn properly in curves, unless you define them as the bogie, not the Main of the second unit. It might be possible if it would be allowed to position the bogies any way you like, but they absolutely must be behind and forward of the Main pivot. I have tried to put them both to the same side of the Main pivot point, but MSTS crashed.