[steamer_ctn]

Just a reminder that we don't have enough information to build the Booster physics model yet.

In the meantime, I have found this document that has provided some basic information.

On page 104 (pdf page 107) of the 1938 Locomotive Cyclopedia found on this site, it refers to a report submitted by "Locomotive Design and Construction of the American Railway Association" group in 1924. There is a reference in the footnotes on this page to formulas to calculate the tractive effort of the booster. I would like to obtain a copy of this information. Does anybody have access (possibly through a professional association that they are a member of or a library) to the document indicated? Alternatively does anybody have access to a formula to calculate the tractive effort for the booster?

Further down in the document (from about pg 126 onwards) a number of locomotives are shown which have the boosters mounter on the tenders. So the complexity of the coding has increased somewhat.

[scottb613]

steamer_ctn, on 12 January 2023 - 09:15 PM, said:

Just a reminder that we don't have enough information to build the Booster physics model yet.

In the meantime, I have found this document that has provided some basic information.

On page 104 (pdf page 107) of the 1938 Locomotive Cyclopedia found on this site, it refers to a report submitted by "Locomotive Design and Construction of the American Railway Association" group in 1924. There is a reference in the footnotes on this page to formulas to calculate the tractive effort of the booster. I would like to obtain a copy of this information. Does anybody have access (possibly through a professional association that they are a member of or a library) to the document indicated? Alternatively does anybody have access to a formula to calculate the tractive effort for the booster?

Further down in the document (from about pg 126 onwards) a number of locomotives are shown which have the boosters mounter on the tenders. So the complexity of the coding has increased somewhat.

Hi Peter,

Hah - it isn't due to lack of interest. I have a few irons in the fire at the moment which have been impacting my ORTS time. Before the boosters came along - I had started work - helping James - trying to improve the ORTS environment.

I don't have any special access but I will look for the documentation along with the original PDF you asked me for regarding Tender Boosters.

I did take a preliminary look at the Niagara - while I'm sure it was a good model for the time - there's not much to work with here - from a modeler's perspective. As for the physics - they look like they have been updated a bit with ORTS features. The file mentions using documentation for performance numbers - but no documentation was included - is this the document used?

Road Testing Niagaras
https://nycshs.files...ingniagaras.pdf

Regards,
Scott

[steamer_ctn]

scottb613, on 13 January 2023 - 04:49 AM, said:

Hah - it isn't due to lack of interest. I have a few irons in the fire at the moment which have been impacting my ORTS time. Before the boosters came along - I had started work - helping James - trying to improve the ORTS environment.

No problems. I wasn't chasing you up as such, but more providing some feedback on my investigations.

There were a few other people who have expressed an interest in this feature, so I wouldn't expect you to be the only person providing appropriate input.

Given that this feature may need to be implemented either on the locomotive or the tender, complicates it, so it won't be done in a hurry.

I also wanted this thread to serve as an example of the amount of effort required to potentially implement a new feature despite the fact that it might sound simple. Sometimes the research takes quite some effort.

scottb613, on 13 January 2023 - 04:49 AM, said:

I don't have any special access but I will look for the documentation along with the original PDF you asked me for regarding Tender Boosters.

Hopefully some others might have ways of accessing the information.

scottb613, on 13 January 2023 - 04:49 AM, said:

I did take a preliminary look at the Niagara - while I'm sure it was a good model for the time - there's not much to work with here - from a modeler's perspective. As for the physics - they look like they have been updated a bit with ORTS features. The file mentions using documentation for performance numbers - but no documentation was included - is this the document used?

Yes it was the main document, though there were a couple of Niagara documents.

At the time, I didn't have access to any better information on "modern" steam locomotives, so I went with that. I have some test reports for the T1 and Q2 locomotive so potentially we could go with those instead.

If we go ahead with this feature, we will need a locomotive and tender based example.

[Jonatan]

One potential thing required for the booster feature would also be its own sound triggers and steam FX?

[scottb613]

steamer_ctn, on 13 January 2023 - 04:35 PM, said:

If we go ahead with this feature, we will need a locomotive and tender based example.

Hi Peter,

All very cool - I just didn't want you to think I wasn't interested.
:)

I think Brandon posted that he might be willing to build that Niagara for you. He's definitely a 4-8-4 guy.

Please keep in mind that creating a locomotive from scratch is no small feat - it's 9 months to a year of steady work - at least for me. So - I wouldn't expect anything in the short term - that we could use.

That said - if you want functional "mock ups" for testing - we can do that. I could probably hobble together something in a week.

For the booster on the trailing bogie/truck example - we could use the Pacific I am already working on - I could share the model "as is" for testing - and it will eventually be completed. I've already done the physics for it.

I could "mock up" a second model with a booster in the tender with animated side rods (need to verify functionality) and a stack for exhaust. I'm thinking 2-10-2 Santa Fe.

If this is acceptable - just let me know and I'll start work on the tender booster example.

Regards,
Scott

[scottb613]

Jonatan, on 13 January 2023 - 08:04 PM, said:

One potential thing required for the booster feature would also be its own sound triggers and steam FX?

Hi Jonatan,

Yeah - hopefully Brandon will dive in on the sounds creation - as that's one area I haven't really messed with.

Regards,
Scott

[Weter]

To Brandon:
That man, whom I've mentioned in this post as an author of smoke FX code is Robert Murphy

[ATSF3751]

Thank you Weter. I may have to PM him at some point.

As Scott mentioned yes I am a big 4-8-4 guy so of course I would be willing to build a NYC 4-8-4 along with some custom sounds for it as well. I think if Scott, Peter, myself and a few others all work together we could get the Steam Locomotive code narrowed down the way we want it in the Sim. I know Peter needs help with it and its time for us to step up and help him out as he has already gotten us this far with it.

As for testing is concerned I feel we need multiple steam locomotives of different types that are all set up the same way in the coding so we can narrow down what works and what does not so we can figure out what needs more tweaking. We have many fairly good models out there already for both the US and UK steam locomotives that we should be able to use if we set them up properly in the same respect for Open Rails coding.

I was thinking of doing the Flying Scotsman, Mallard and Tornado in the updated Open Rails coding and see how those three locomotives perform in the Sim. The reason I picked these three as they all have good models built of them. All three of them were designed to run at high rates of speed with lighter trains. One more aspect to put into account is they all have three cylinders as well.

While most US steam locomotives were built for power and long distances UK steam locomotives were built for speed and short distances. Of course I would be willing to build a few other steam locomotives as well if needed but lets start with the NYC 4-8-4 first.

Going back to boosters one locomotive I do know has one is FRISCO 1522. We already have a model of it for Open Rails thanks to Derek who built it a few years ago so maybe we could use that locomotive to start off. I do believe the booster is on the tender but not 100% sure. I would have to watch some videos of it to figure it out.

However,

I am currently working on a Rock Island 4-8-4 that we could possibly use if we wanted along with my Milwaukee Road S3 261 that I just recently came out with as well.

Here are some different specs for all three Locomotives

Milwaukee Road S3

6 were coal and 4 converted to oil

BASIC INFO

Height – 15′ 6″ Length – 109′ 7 3/4″
Fuel- Soft Coal
Coal Capacity – 25 Tons
Water Capacity – 20,000 Gal
Boiler Pressure – 250 Lbs
Cylinders – 26″ x 32″
Driver Diameter - 74"
Tractive Effort – 62,119 Lbs
Factor of Adhesion – 4.18
Tender Type – 12-wheeled; consisting of two 6 wheel trucks

WEIGHT IN WORKING ORDER

Leading Truck – 87,000 lbs
Driving – 259,300 lbs
Trailing Trucks – 113,700 lbs
Total Weight in working order – 460,000 lbs
Weight of Tender with fuel – 364,100 lbs

OTHER RANDOM STATS

Fire Box Area – 144 9/16th” x 96 1/4″
Grate Area – 92.6 Sq. Ft.
Total Evaporating Area – 4477.5 Sq Ft.
Total Heating Surface – 1,438 Sq Ft.

Rock Island R67B 4-8-4

Half were coal and half were oil

BASIC INFO

Height – 15′ 9″ Length – 107′ 6 1/2″
Fuel- half Soft Coal half oil
Coal Capacity – 20 Tons
Oil Capacity - 5,500 Gal
Water Capacity – 15,000 Gal
Boiler Pressure – 270 Lbs
Cylinders – 26″ x 32″
Driver Diameter - 74"
Tractive Effort – 67,088 Lbs
Factor of Adhesion – 4.17
Tender Type – 12-wheeled; consisting of two 6 wheel trucks

WEIGHT IN WORKING ORDER

Driving – 280,000 lbs
Total Weight in working order – 837,500 lbs
Weight of Tender with fuel – 370,500 lbs

OTHER RANDOM STATS

Fire Box Area – 144 9/16th” x 96 1/4″
Grate Area – 96.30 Sq. Ft.
Total Evaporating Area – 4,573 Sq Ft.
Total Heating Surface – 1438 Sq Ft.

NYC Niagara 4-8-4

BASIC INFO

Height – 14′ 11 1/2″ Length – 109′ 7 3/4″
Fuel- Soft Coal
Coal Capacity – 46 Tons
Water Capacity – 18,000 Gal
Boiler Pressure – 275 Lbs
Cylinders – 25.5" x 32"
Driver Diameter - 79"
Tractive Effort – 61,568 Lbs
Factor of Adhesion – 4.47
Tender Type – 12-wheeled; consisting of two 6 wheel trucks

WEIGHT IN WORKING ORDER

Driving – 259,300 lbs
Total Weight in working order – 808,000 lbs
Weight of Tender with fuel – 364,100 lbs

OTHER RANDOM STATS

Fire Box Area – 503 Sq. Ft.
Grate Area – 92.6 Sq. Ft.
Total Evaporating Area – 4,823 Sq Ft.
Total Heating Surface – 2,073 Sq Ft.

[Traindude]

In regard to boosters and smoke/steam emitters, there's something to consider--the booster exhaust piping is different for different locomotives.

In this photo of the famous New York Central Hudson, you can see what looks like a small, thin smokestack ahead of the main smokestack. That is the booster exhaust stack, which has its own separate exhaust nozzle within the smokebox. As such, it would behave just like the main stack's emitters, but in sync with the rotation of the rear trailing axle and not the main drive axles.

On some locomotives, like this Texas & Pacific 2-10-4 Texas Type, the exhaust piping is completely outside the boiler and smokebox, but still terminating in front of the main stack. In this case, it stands to reason that the exhaust would appear as a white stream of steam, sort of like the GeneratorFX, albeit "pulsing" 4 times per trailing axle rotation.

On other locomotives, no separate exhaust pipe or stack is provided, and instead the booster exhaust is routed through either the main blast nozzle or the exhaust passages in the main cylinder saddle, and as such it would cause the main stack emiiters to "pulse" in sync with the rotation of the rear trailing axle in addition to the main drive axles. However, the velocity of the booster exhaust pulses would not be as strong as the main exhaust pulses.

I hope this makes sense.

[ATSF3751]

I just happened to come across a treasure trove of info about the NYC for anyone that is interested. https://nycshs.org/n...ch-information/

Here is all of the info about the NYC Niagara as well.

https://nycshs.files...agara-story.pdf

https://nycshs.files...1/niagara21.pdf

https://nycshs.files...ingniagaras.pdf