[markus_GE]

Eldorado.Railroad, on 19 August 2014 - 11:59 AM, said:

Markus,

The term "does not work for me" can also mean, one size does not fit all. So I am sure that for many the DPU program you worked on is what is wanted/needed, and for them I say danke! Since I work with actual models and textures, I am a bit more particular and as I have mentioned to you before I would dearly like DPU to dump the altered .eng file in the openrails directory (that has to be created) for any given engine. But is is time for you to enjoy your holidays and always remember that is the most important thing. When you come back, refreshed, you might want to tackle some of the requests that showed up for your program.

Have a great vacation!

It´s logical one size will never fit all, especially seeing ow samll the current one is. Anyway, the planned next revision is hopefully going to improve the situation a bit in that regard.

Could you please check if the wish WRT where to dump the altered ENG file has already been added to the DPU thread? (Lin in my last reply) I´m on a slow-as-molasses-flowing-up-the-hill-in-winter hotel WIFI connection that will probably take 5 minutes to get this post out of Page, AZ...

:) for the wishes. It´s been REALLY great so far, but there´s still two thirds of the journey left :sign_oops:

Cheers, Markus

[atsf37l]

copperpen, on 24 August 2014 - 03:03 AM, said:

With standard settings those kind of speeds should not be possible. The main speed denominator is the friction. Remove that and high speeds are possible. Use proper friction figures and normal speeds will apply, except when running downhill when gravity takes over, until friction catches up again.

However, you are correct in that the faster you travel the higher the steam goes before forward speed takes effect on the plume, which is contrary to normal physics.

Friction certainly plays a part to be sure but with a steam locomotive, no matter how big your intake and exhaust ports are there is only so much steam or air that can be cycled through a set of cylinders and once that limit is reached you are not going to go any faster. Further, steam engines are balanced for the maximum normal speed and the flailing of the rods at these kinds of speed will also be a limiter of not only the speed attained but the durability of the locomotive. At 500 MPH that CP loco would disintegrate before your eyes with bent and broken rods taking out ties and rail and wheels. :) :sign_oops:

[atsf37l]

How about an exhaust sound question? Why do steam locomotives chuff when drifting or going downgrade in ORTS? This is completely unprototypical. When the throttle is closed on a steamer you don't hear chuffing. Hiss from appliances, turbogenerator whine, rod clanks yes but no exhaust chuffs. With all the discussion here about cutoff and exhaust ports this should be self evident and needs to be fixed.

[copperpen]

There are several things that need to be added to the steam locomotive code and altered in the effects code for visual and sound. So we take it one step at a time.

Far as chuffing when the throttle is closed goes, once rolling the throttle is never completely closed in order to prevent the cylinders from ingesting exhaust gas and cinders, so there will always be a faint chuff. Maybe this is something that can be tied to the throttle setting instead of speed, or an extra wav file to be played when throttle is closed and engine is moving.

[gpz]

Variable2 is proportional to how hard the locomotive is working. A good sound set uses this variable as a chuffing volume control, thus it is not heard when the throttle is closed. If you hear it, them it is a problem of the sound set.

[atsf37l]

copperpen, on 26 August 2014 - 03:39 AM, said:

Far as chuffing when the throttle is closed goes, once rolling the throttle is never completely closed in order to prevent the cylinders from ingesting exhaust gas and cinders, so there will always be a faint chuff.

I beg to differ. With British steam on your mostly level gradients there is normally a need for some application of steam to the cylinders in order to maintain speed.

With American steam when going down our long and by British standards excessive grades, even with the throttle cracked and the Johnson bar full forward, there is no chuffing sound. Further, this open throttle coasting is helpful to lubricate the cylinders on long coasting sections but in switching moves the throttle is frequently closed completely as the locomotive is coasting to a joint or moving about the yard. These are short drifting actions that don't require the lubrication protection that a long hill would necessitate and should therefore be silent.

The correct sound sequence for drifting or switching is not currently possible in OR because of this chuffing that should not be there. :)

[copperpen]

Not arguing here Herb, but there has to be some sound because a small amount of steam would be needed to carry the lube and to generate the positive pressure on the exhaust side. It certainly would not be very loud, which is why it is never heard from the trackside even over here.

[atsf37l]

copperpen, on 26 August 2014 - 12:02 PM, said:

Not arguing here Herb, but there has to be some sound because a small amount of steam would be needed to carry the lube and to generate the positive pressure on the exhaust side. It certainly would not be very loud, which is why it is never heard from the trackside even over here.

I agree in principle so let's address the sounds as they exist in OR. The chuffing is very well heard from trackside in OR, and it is much louder from the cab-headout view than I've ever experienced on a drifting loco. I will tell you from experience that D&RGW C-19's and K-36's don't make a sound when drifting other than rod clank. If the sound is there it is imperceptible from cab or trackside and that's not what I'm experiencing in the sim.

Remember that the drifting throttle concept is a two-fold exercise: A very small amount of lubricated steam is admitted, and; full forward on the reverser. Meaning that there is very slight steam admitted for the entire stroke of the piston and exhausted for the full stroke of the piston, therefore producing none of the "crack" of the opening exhaust port which causes the "chuff." At best the sound would be a faint hiss not the sharp exhaust sound we're getting in OR.

Regarding your earlier assertion that the opening of the throttle prevents the cylinders from sucking in abrasive particulates from the smokebox, American engines have "snifters," or "drifting valves" that sense when a vacuum is created in the cylinders and open to admit outside air, preventing that sucking of the nozzle. So the only need for steam is for lubrication to keep the cylinders from getting hot and if you have a mechanical lubricator on the engine you don't even have to do that. It will feed lubrication to the cylinders without steam admission.

Add to that, opening the throttle a crack to lube the cylinders should be an engineer's decision, not the software's decision.

Bottom line, zero throttle should be whisper quiet. :bigboss:

[gpz]

And the bottom-bottom line is that again: if you hear chuff with throttle closed, then it is a problem of the sound set in use, not any missing feature in OR.

[captain_bazza]

...Ode to the oddity of it all...

They also serve, who stand and stare,
Offering advice from here and there!

Whether about the note of the beat,
Or, "That smoke and steam looks neat."

Dear programmers, all, please don't fret,
There'll be equal bricks, and praise, I bet.

Cheers Bazza. :pardon::oldstry: