[steamer_ctn]

Based upon some earlier work by cesarbl I have reworked the adhesion model for steam locomotives.

More details will follow.

[scottb613]

steamer_ctn, on 20 December 2022 - 05:14 PM, said:

Based upon some earlier work by cesarbl I have reworked the adhesion model for steam locomotives.

More details will follow.

Hi Peter,

A-n-t-i-c-i-p-a-t-i-o-n...


:)

Regards,
Scott

[Jonatan]

Sounds interesting.

[ATSF3751]

Looking forward to what you have to say Peter! Thank you again for all of your hard work!

[steamer_ctn]

I have now uploaded the changes to the unstable version, and also set up a test model (NYC Atlantic) based upon a "real" description.

The model is here.

I would suggest that the model is run under different circumstances to develop an understanding of how slip works in this new variation.

Once you are happy with the testing of the model provided, feel free to try your own model.

[Laci1959]

Hello.

Surely this will be good? I don't see the ORTSNumberAxles and ORTSNumberDriveAxles lines. Then these two rows are no longer needed to adjust the steam locomotives? The ORTSDriveWheelWeight line is also not needed after this? Or does it not matter what value is entered, because it does not affect anything? At least it doesn't affect adhesion.

Sincerely, Laci 1959

[scottb613]

Hi Peter,

I haven't delved into looking at configs like Laci - but - I did see slippage in your example and it looks quite a bit better - when I hit the sander it stopped slipping. You have some time to catch it before it runs away. Make sure you have the key to slam the Regulator closed - mapped to a joystick or handy. Nice work to both you and Ceasar.

Regards,
Scott

PS - you don't have to actually slam the regulator closed - simply backing off a bit will stop the slippage. All testing done on dry track. I like it. My much larger locomotive won't slip under the same test conditions.

[ATSF3751]

Milwaukee Road 261 wont slip either under those conditions Scott but it will slip when in rain or snow. I have to agree that it is quite a bit better then before but I think it could still use a little tweaking. Great work Peter!

Brandon

[steamer_ctn]

Laci1959, on 22 December 2022 - 03:15 AM, said:

I don't see the ORTSNumberAxles and ORTSNumberDriveAxles lines. Then these two rows are no longer needed to adjust the steam locomotives? The ORTSDriveWheelWeight line is also not needed after this? Or does it not matter what value is entered, because it does not affect anything? At least it doesn't affect adhesion.

Thanks for picking this up. It was a cut and paste of the ENG files, and demonstrates how easy it is for mistakes to creep in.

The old values would have worked (as they did), however better practice is to use the more recently defined values. I have uploaded a minor mode to the model to correct these values.

scottb613, on 22 December 2022 - 05:00 AM, said:

PS - you don't have to actually slam the regulator closed - simply backing off a bit will stop the slippage. All testing done on dry track. I like it. My much larger locomotive won't slip under the same test conditions.

Thanks for the feedback. You may find that you will need to take more care in the wet and snow conditions.

A lot of more modern locomotives had FoA > 4 which made them less likely to slip.

ATSF3751, on 22 December 2022 - 11:10 AM, said:

Milwaukee Road 261 wont slip either under those conditions Scott but it will slip when in rain or snow. I have to agree that it is quite a bit better then before but I think it could still use a little tweaking. Great work Peter!

What tweaking are you thinking about?

[Hobo]

These new settings are not for articulated , duplex , triplex or shay type steam . Correct ?