Locomotive Losing Speed Way Too Quickly?

[PRR4435]

I recently was having a problem with a few steam locomotives that is noticed somewhat while pulling a train and greatly while running light. If it helps to solve the problem, the models are Derek Miller's C-48's which I must say are great models, but they have a slight problem.

While running light on flat track, if the engine isn't receiving any throttle and the brakes are released, it slows down at a rate of .1 MPH, per second (approximately). Maybe I'm wrong but I don't think even an automobile would slow down that quickly on flat road while coasting along, so imagine how bad that rate is for something as heavy as a steam locomotive. It's almost as if there is a hidden brake that is in slight application the entire time.

So, I was wondering if anyone would be able to help me to fix this problem as it seems terribly unrealistic in terms of physics. Thanks.

[rdamurphy]

Two things to try: Make sure both the train brake and independent (locomotive) brakes are released.

Make sure the tender doesn't have a hand brake.

And, oh, BTW, just because track looks "flat" it can be on quite a grade...

Robert

[hiball 3985]

AH yes, steamers with disk brakes I had a little success in the past by adjusting values in the Adhesion line in the .eng file. I think it was the second number set to a lower value. I don't recall how that may effect the pulling power, it's been quite some time since trying this and I haven't tried it on Dereks locos.

[apco25]

Shouldn't the friction be edited not the adhesion? Adhesion would effect pulling power to the rail.

[hiball 3985]

Shouldn't the friction be edited not the adhesion? Adhesion would effect pulling power to the rail.

That's very possible, I've never tried the friction line. But did notice a change when adjusting Adhesion. I mentioned it may effect the pulling power also. I'm not a steam physics expert and MSTS steam physics don't mimic reality too well and never have

[baldwin]

.................MSTS steam physics don't mimic reality too well and never have

Steam physics are modelled quite well, unlike diesel you have to put in a bit of work to get good results.

[hiball 3985]

Steam physics are modelled quite well, unlike diesel you have to put in a bit of work to get good results.

Well you may have the talent to do those mods I don't . But I don't think the out of the box physics and the drunken auto fireman aren't too great

[baldwin]

True, but then neither are the diesel or electrics "out of the box". I have not really done any serious tuning of a steamer for several years now.

Turning to the OP, having done a quick bit of testing on East Metro, The problem lies in the very first figure of the Friction statement. This is in fact the overall wind resistance of the model. Lowering it does allow the engine to roll further, but then I have to ask which is the more real action, slow down slower or quicker. A big American steam engine does present a lot of flat surface to the wind, but a slightly lower figure might be more real because there is also weight and inertia to consider.

This model is not alone in using a high figure in the friction line.

[hiball 3985]

True, but then neither are the diesel or electrics "out of the box". I have not really done any serious tuning of a steamer for several years now.

Turning to the OP, having done a quick bit of testing on East Metro, The problem lies in the very first figure of the Friction statement. This is in fact the overall wind resistance of the model. Lowering it does allow the engine to roll further, but then I have to ask which is the more real action, slow down slower or quicker. A big American steam engine does present a lot of flat surface to the wind, but a slightly lower figure might be more real because there is also weight and inertia to consider.

This model is not alone in using a high figure in the friction line.

That's good info for all of us, I'll try that when I have an opportunity. Thank you