Scale speed inconsistency

[Britannia Builder]

I have a 'Majestic' train set (2 locos and eLink) and I've just added a Duke of Gloucester with TTS sound. The two locos that came with the set run at reasonably consistent speeds (the same speed on the controller screen gives pretty much the same speed on the track) but the DoG is a lot slower - 80mph on the screen gives about the same speed on the track as 40mph for the other two. I then used the 'set speed factor' on the loco setup to make the DoG go faster (I had to use trial and error since the outer oval on the track mat is shorter than the test track specified for setting the speed factor) and I got the 80mph running to pretty much match the other two locos, but the slow running is then not very progressive - increasing from 6 to 10mph gives a dramatic increase in speed, up to at least half full speed.

Can anyone tell me what the scale speed should be - how long should it take for a train running at a scale 80mph to go round the outer loop of the standard Hornby trackmat? I'm not sure whether my original locos are going too fast, or the DoG too slowly. Any thoughts on why the speed difference could have arisen?

Regards, John

[Fishmanoz]

Hi Bb, inconsistencies in scales speeds have been reported before.  May I suggest you add to the refrain by reporting the above to HRMS via the email facility in the Help screen of RM.  Better they fix it than your having to learn about complex speed curves and the CVs needed to implement them to fix your DoG.

[Chrissaf]

Speeds are all relative. What is slow to you may be normal to us etc. It would possibly help if you were to give us some timings for the completion of an oval circuit. For example when set to max speed, how many seconds does it take for the loco to circuit your TrakMat oval.

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Doing the maths...80 MPH equates to 18.5" per second at a scale of 1:76

[Chrissaf]

PS - Just to add a personal view. To my mind, any loco going fast enough to cover 18.5" per second doesn't look realistic on a layout. I am amazed when looking at some of the YouTube videos just how fast some people run their models. I much prefer a more sedate pace, but that is just my personal choice.

[WilliamDavid]

PS - Just to add a personal view. To my mind, any loco going fast enough to cover 18.5" per second doesn't look realistic on a layout. I am amazed when looking at some of the YouTube videos just how fast some people run their models. I much prefer a more sedate pace, but that is just my personal choice.

You keep missing the point.

If, using Railmaster correctly, one Hornby loco goes much faster than another when showing the same speed, something is not right.

A Tornado doing 80mph should be the same as a King at 80mph.

[Chrissaf]

Some further maths.....assuming a standard TrakMat outer oval is about 16 feet, then 18.5" / sec would be about 11 seconds.

[WilliamDavid]

ps. Support never came back to me on this. Either they don't understand, or can't fix it.

Double heading is not possible the way things are.

[WilliamDavid]

ps. Where is that edit facility?

[WilliamDavid]

Some further maths.....assuming a standard TrakMat outer oval is about 16 feet, then 18.5" / sec would be about 11 seconds.

I too, think that lower speeds on a typical layout are more pleasing, but.

A Tornado indicating 40mph should run at the same speed as a King indicating 40mph.

[Chrissaf]

You keep missing the point.

.

I fully understood the OP's question and how it related to locos going at different rates for the same controller setting. I was focusing my reply on the second part of the question as below.

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Can anyone tell me what the scale speed should be - how long should it take for a train running at a scale 80mph to go round the outer loop of the standard Hornby trackmat?

 

[Chrissaf]

Checked the Hornby track geometry documentation this morning. The TrakMat 3rd radius oval is nearer 14 feet than the 16 feet I originally estimated. This would equate to 9 rather than 11 seconds at a scale 80MPH.

[Britannia Builder]

Thanks for all your replies. I'e timed my two original locos on the outer oval and they do indeed take 9 seconds at 80mph. The DoG after adding my speed factor is in fact slightly faster at about 8 seconds, but after deleting and re-loading the loco definition to get the original settings it takes 11-12 seconds at 80mph (the default fast speed is 70mph). I'll try tinkering with the speed factor again, by taking the ratio of the track oval length to the RM standard test length and putting in timings adjusted accordingly to see what happens. I agree that the slower speeds are more pleasing, but my grandsons like to see them racing each other!

Will running the new loco in make any difference, or does the DCC chip measure the actual motor speed rather than just giving a set voltage?

Regards, John

[Yelrow]

Sorry to chip in, but double headers work fine. have a bachmann one, and a hornby diesel one, and they are perfect. john

[Britannia Builder]

I've now found by trial and error that entering a time of 5.3 seconds for a hypothetical circuit of the 2.75 metre track in the speed factor setting gives a perfect match against my other two locos, and good slow speed control. It's a bit fiddly to try different speed factors because I needed to delete the loco and set it up again each time.

 

Regards, John

[Fishmanoz]

WD, when you say support (I trust HRMS not HCC), never got back to you, did you email them from within RM or at the support@ email, did you get the auto acknowledgement, and then no further reply.  We do know they know there are scale speed issues as yet unresolved, so maybe they are still working on it.  It's why I asked Bb to contact them too.

 

Bb, glad you've solved your problem, but do please let HRMS know.

 

John, your double headers working means the scale speeds are working for your particular locos, other people's aren't. 

[96RAF]

As of yesterday I'm still in comms with HRMS about my Class 395 throttle problem that is scale speed related - i.e. when scale speed is on, large throttle won't stop the loco, but when scale speed is off it does.

 

I haven't compared any 2 or more locos running at the same indicated scale speeds to see if they match progress or not, but could do if it would add to the knowledge base.

[NormanQ4]

Sorry to chip in, but double headers work fine. have a bachmann one, and a hornby diesel one, and they are perfect. john

I have two Bachmann's which appear to run ok as double headers but when run individually they run at very different speeds on the same throttle setting.

I think when in double header format one is pushing / pulling while the other is being pushed / pulled, but how do you tell.

[AncientMariner]

Sorry to chip in, but double headers work fine. have a bachmann one, and a hornby diesel one, and they are perfect. john

I have two Bachmann's which appear to run ok as double headers but when run individually they run at very different speeds on the same throttle setting.

I think when in double header format one is pushing / pulling while the other is being pushed / pulled, but how do you tell.

Try looking at the coupling between the locos when running ahead/astern. That might give you a clue as to which one might be pushing/pulling.

 

AM

 

 

[Chrissaf]

Or put them on the track one behind the other, but uncoupled and see which one either catches up or pulls away.

[Britannia Builder]

Reverting to my original issue with the DoG scale speed, I've experimented further by changing CV 150 from 0 to 1 to try the other motor control algorithm. This gives pretty much the correct scale speed at 80mph (in fact slightly too fast) without setting a speed factor - I reloaded the loco definition to remove the one that I set in my post of 1 April above, since I couldn't see a way to reset to the default in the user interface. It also gives very smooth slow running at a crawling pace at 5mph, distinctly better than algorithm 0 which is slightly jerky, but in moving from 5mph to 10mph it speeds up dramatically (to about the equivalent of 30mph on my Class 47), so the speed control is not very linear. I've tried a few changes to the parameters in CV 153 and 154 but I couldn't detect what difference they made, if any. Can anyone tell me what these parameters do?

 

Regards, John