[Traindude]

I was hoping to revisit something I suggested some time ago:

In the steam era, it was a very common for a locomotive to receive two or more different tenders during its operating career. For example, in the US, many locomotives that were delivered with four-axle tenders were given larger, six-axle tenders by the ends of their careers.

However, in MSTS and OR this currently creates a problem since the tender capacities (MaxTenderWaterMass and MaxTenderCoalMass)are specified in the locomotive .eng file instead of the tender .wag file. So in other words, you can couple a larger tender to a pre-existing locomotive in your favorite consist editor, but it won't make any difference in regards to how much water and fuel you have at the start of an activity. Instead, you have to create a duplicate .eng file for the same locomotive, with the water and coal capacity values altered to reflect the larger tender.

Given the successful implementation of auxiliary tenders in OR, we should try to make a system so that the "main" tender capacities can be varied depending on the size of the tender model coupled to the locomotive.

Here's how I imagine such a system working:

1. While the activity loads, OR does a read of the MaxTenderWaterMass and MaxTenderCoalMass values in the locomotive .eng file as usual.
2. Then, OR does a read of the tender .wag file and looks for the presence of any MaxTenderWaterMass and MaxTenderCoalMass parameters:
a. ) If there are MaxTenderWaterMass and MaxTenderCoalMass parameters specified in the tender .wag file, OR compares these values in the tender .wag file with the MaxTenderWaterMass and MaxTenderCoalMass values previously read from the locomotive .eng file. If the tender .wag file's MaxTenderWaterMass and MaxTenderCoalMass values are anything greater or less than those in the locomotive .eng file, the .eng file values are overridden and the tender .wag file values are used instead for the duration of the activity.
b. ) If there aren't any MaxTenderWaterMass and MaxTenderCoalMass parameters specified in the tender .wag file, then OR uses the values previously read from the locomotive .eng file.

What are your thoughts? Vote for this feature on Trello!

[longiron]

Seems reasonable for most typical steam locomotives. What about articulated and Garrett locomotives that may have multiple ENG files but only a single tender WAG file?

[Traindude]

longiron, on 04 January 2021 - 04:22 AM, said:

Seems reasonable for most typical steam locomotives. What about articulated and Garrett locomotives that may have multiple ENG files but only a single tender WAG file?

I still need to figure that out TBH...

[copperpen]

Garrets are easy, one eng carries the water and the other has the fuel, just as in real life. Most articulated engines as they are currently modelled present a different problem with the current workaround making the lead engine into a tank locomotive. The exceptions are those modelled by Jon Davis, single eng files for the whole locomotive.

[steamer_ctn]

Traindude, on 03 January 2021 - 12:57 AM, said:

Given the successful implementation of auxiliary tenders in OR, we should try to make a system so that the "main" tender capacities can be varied depending on the size of the tender model coupled to the locomotive.

Since it appeared to be a trivial coding exercise, I have added your suggested functionality to the latest unstable release version.

It should work along the lines that you described, and uses the following parameters in the tender file:

ORTSTenderWagonCoalMass and ORTSTenderWagonWaterMass

I would not recommend removing the default values in the ENG file, as this may cause some issues.


Changing the tender in mid activity will not change the coal/water mass values.

[Traindude]

steamer_ctn, on 06 January 2021 - 08:47 PM, said:

Since it appeared to be a trivial coding exercise, I have added your suggested functionality to the latest unstable release version.

It should work along the lines that you described, and uses the following parameters in the tender file:

ORTSTenderWagonCoalMass and ORTSTenderWagonWaterMass

I would not recommend removing the default values in the ENG file, as this may cause some issues.


Changing the tender in mid activity will not change the coal/water mass values.

I'll try it out! Thanks!

EDIT: Works great now!

[Genma Saotome]

I suspect the original (KUJU) thinking was WRT handling tenderless steam locomotives.

IMO the best answer is two part:

• Move ev erything about the tender currently found in the .eng file to the tender .wag
  
• Add an optional block in the .eng file called NoTender(list of other parameters()) or something like that with the same data just moved to the tender .wag

AFAIK that should take care of everything. Perhaps Peter Newall might be interested in doing this.

[steamer_ctn]

Genma Saotome, on 08 January 2021 - 11:51 AM, said:

• Move ev erything about the tender currently found in the .eng file to the tender .wag
• Add an optional block in the .eng file called NoTender(list of other parameters()) or something like that with the same data just moved to the tender .wag

If we lived in a perfect OR world then this might be worth doing, however whilst there is still a requirement to maintain some level of legacy operation with MSTS defined stock, then a system where the tender information is either in the ENG file or the tender file needs to be maintained.

The patch implemented maintains this approach.

[Weter]

There is a bug with MSTS AE's consist editor, due to that fact, that tenders considered as a freight cars (it likely can't determine their right place in given categortes: engine/freight/coach), but more correct would set the special "tender" type.

Second: as in MSTS we can specify BarCoupleUniqueType at *.eng/*.wag - files, it would be good for us to have an opportunity of specifying compatible tender types for steam engines, as we know, that it could be more, than one possible variant IRL

This post has been edited by Weter: 09 January 2021 - 12:30 AM