Stringfingerling

My Heljan O Gauge mogul has a Loksound V5 decoder in it which, I think, has just expired. I fitted the decoder myself and I've had numerous adventures with the loco, getting it to run nicely, and the other day, I thought I had finally got everything going really well, no pickup problems, smooth running etc - but this morning, the running was stuttery and lumpy, before the loco refused to start again. It now emits a buzzing sound (from the decoder in the tender) as soon as the track is powered up - before any instructions are sent to the loco. The controller and track are fine - other locos work without problems.

1) Is this terminal for the decoder?

2) Has this happened to anyone else?

3) Should I replace it with the same model of decoder, bearing in mind that the model has been designed around that decoder?

4) I would be happy to pay an expert (I live in Kent) to fix this. Any recommendations?

In a modest GW country station, where the goods yard and facilities are accessed through the same road entrance as the station buildings, were there any rules or guidelines about keeping members of the public away from goods facilities with fences, either for their safety, or for security of goods in transit?  Looking at a lot of photos, it's hard to see evidence of a standard rule about this.  If there was a set of rules, were they followed in practice?
Also, where there is a cattle dock/pen in the goods yard, would there have been any rules about how animals would be brought into the yard, to avoid either animals being injured by trains, or leaving droppings on the ground where passengers would be obliged to walk?

10 hours ago, GWR57xx said:

@Stringfingerling sorry, only just found this thread.

My first 43xx (eventually returned for a replacement) was jerky at slow speed, but only running forwards. It ran nicely in reverse. This was due to a chewed up drive gear. The brass worm gear on the motor shaft couples to a straight cut plastic (nylon?) drive gear, so only the very edge of the drive gear is engaged, and it’s the opposite edge when running in the opposite direction. 
The replacement also ran a bit lumpy at first, but after four hours of running in on a rolling road it now runs sweetly in both directions.

I’m not sure how effective your running in would have been if the driving wheels were dangling free and under no load.

I’d suggest quite a bit more running in, on a rolling road if possible.

Glad to hear you've got one that works now    Mine has definitely improved with use.  I smoothed out the running surfaces of the slide bars as they seemed a bit rough and made sure the backs of the crosshead had no jaggy edges, as, to begin with, I was getting the occasional clash with the front crankpins.  I haven't even opened mine up to look at the gears, though I know what they look like from your and other people's photos.   Some of my problems were not really Heljan related but to do with decoder settings for the Loksound V5L.  I've got it much closer to the way I want now, though it's never going to be perfect.  Mine will run smoothly in both directions but there's something about the running when it is pulling a train that is not quite as silky smooth and consistent as I would like, but it's good enough.  The rolling road is a good idea I'm sure.

1 hour ago, Nigelcliffe said:

Yes,  could alter the CV programming so F17 was now "not F17" to engage shunt mode, and "F17" puts the loco into normal mode.   its a single CV change.   From the last time I setup a LokSound decoder, I'm pretty sure that will work from first selection of the loco as on initial selection it will be "not F17".  

 

But, "which CV" is a more complicated question.  Depends who wrote the sound project, and how they set it up.  So, they could tell you what to change.     Or, if you have a computer interface, you could read the function mapping in JMRI and make the change.   Doing it manually is reading potentially 72 different CV's to find which one applies.   

 

- Nigel

Thanks Nigel, an interesting idea.  I'll get in touch with the person who I believe did the sound project.

1 hour ago, Richard Croft said:

Read CV5 which is maximum speed then halve it, this will limit the top speed of the loco to half of its current speed, like shunting mode does

 

Richard

Hi Richard, I know that works as a way of reducing the speed range, but I also want to make use of the much quieter and gentler chuffs that are available in shunt mode.

F17 allows me to enter shunting mode on my Loksound V5L.  It works fine - as long as I have already run the loco - however briefly in normal mode.  I would like to be able to start "from cold" in shunting mode, as the nature of my layout means I do not normally want to use the "normal mode".   Is there a way around this please?

33 minutes ago, 47606odin said:

Has it been properly run in and lubed? Things run better when a bit loose

I ran it  static, with the wheels suspended above the track in each direction for an hour when I got it.  I haven't added any extra lubrication.

I've had my mogul since the end of December and it hasn't been plain sailing; I had a few issues with the DCC, but that is now fine.   
I'm still not content with the slow running.   You could live with it if the loco was mainly used on trains that maintain a steady speed, but my layout is all about arrivals, shunting/running around the train and slow departures.
It doesn't stall and there is no interruption to the sound but it does have a noticeable random jerkiness which detracts from the sense of it being a heavy locomotive.  There is a stay alive in the Loksound decoder.   A number of people have suggested extra pickups, and I may well pursue this route.  One contributor who had fitted one axle's worth of pickups to the loco still found some judder.  Jon Fitness suggested enquiring whether spare parts designed for the Heljan prairie would do the job, as the chassis ought to be pretty similar.   It occurred to me that I could divert the wiring for the under-chassis loudspeaker for use with pickups on the loco itself, as I'm not using the chassis cavity for a speaker.  (My speaker is in the tender).   The point of this would be to avoid extra fiddly wiring and connectors between loco and tender.   
I noticed though, that occasionally the centre tender wheels are not rotating, as they are not dropping into slight dips in apparently level track.   The tender has no flex in its suspension so it must be riding (and picking up power) from just the outer four wheels.  Given that it is of a rigid design, I wonder if it's sometimes even reduced to three wheels firmly in contact with the track?
Adding extra loco pickups would certainly be easier than modifying the tender suspension to include some kind of compensation or springing.
I'm guessing that what happens when the loco jerks is that there is a momentary lack of power which slows/stops the motor and the gear driven by the motor shaft worm continues to turn.  When the motor restarts or picks up speed it then re-engages the worm causing a judder, because of the slop in the mesh between the worm and the gear.
I assume other people must have the same issue.   I'd be very interested to hear of successful strategies for improving this.
 

I am very pleased with VSDC which I've used a lot.  The free version is ok to start with but the paid version (about £20-30) per year is really good.  It's not perfect; you have to get used to a few quirks in the interface, but it's very good at opening all sorts of video formats and has loads of options for exporting the finished product.  It has a multitude of editing features.  With a little patience while getting started I'd say it's not hard to learn and there are many tutorial videos on YouTube. As with all video software, a reasonably powerful computer helps, but there are quite a few built in features which assist with improving preview performance etc.  
Not available for macs though - PC only.
 

41 minutes ago, wiggy1 said:

Voltage.

I'm assuming you have done an autotune otherwise I doubt that you would have changed that.

Doing an autotune reduces that CV setting.

 

Wiggy.

Yes I did do the Auto-Tune. I assume that means the procedure where you you set CV54 to 0 and light the blue touch paper while the Loco runs off and then stops.

1 minute ago, wiggy1 said:

 

Did you have to alter the chuff settings?

With CV53 so low it should have an effect on the BPR?

Cv's 9, 56, 116-119 are motor default settings.

 

 

 

 Peter,

Are you having problems with your O gauge 43xx?

 

Wiggy.

I did change the chuff settings earlier and they seem reasonably good now but since adjusting the speed curve I haven't really checked them. My main aims were to get earlier acceleration and deceleration along with preserving the ability to coast. I can't remember off hand cv53 does?

20 minutes ago, GWR57xx said:

 

I would be very grateful if you could let me know the values you have for CVs 2, 9, 51, 52, 53, 54, 55, 56, 116, 117, 118 & 119.

Thanks,

Peter

Hi Peter - Here are the values.  It may be worth noting that I've changed my speed curve by altering CV's 68 to 93 for earlier acceleration.
CV
2   = 5
9 = 40

51=31

52=7

53=91

54=43

55=30

56=255

116=50

117=150

118=15

119=20

If anyone is interested, I have now got the Mogul running much more as I would wish!  Fiddling with CV's 68-93, I have been able to raise the profile of the speed curve so that the loco initially accelerates a bit more briskly and has less dramatic acceleration further up the speed range.
Happy to post some CV values if anyone wants.

27 minutes ago, GWR57xx said:

I’ve been messing about with CVs all day as well and have failed to get the result I want, which I am sure is possible.

Trouble is the ESU manual is very superficial in its descriptions of CVs and leaves more questions unanswered than not.

I thought it was CVs 3 & 4 that controlled acceleration and deceleration? As in the values in those CVs set the time from standstill to max speed (CV3) and from max speed to standstill (CV4)?

CV5 is max speed, CV6 is obsolete on the V5 ( which always uses the 28 step speed table) but used to be mid-point for a “3 point speed line” on V4 and earlier.

At least, that’s how I understand it, but I think the manual probably lost quite a lot in translation from the native German.

 

I agree, some of the manual is in weakly translated English, and, yes, I think unless you're a serious programmer you can't do anything with CV 6, but it strikes me that you could use the facility to set each of 28 steps on the speed curve individually , if you can spend the time;

Between speed step 1 and the maximum speed, LokSound 5 decoders will superimpose the speed using a speed curve. The speed curve hast 28 values (Cv 67 to 94). The CVs 67 and 94 are permanently set to the values of 1 respectively 255 in this decoder. The intermediate values can be distributed at will. The speed curve can not be switched off. CV 2 and CV 5 define a scale factor around which the points of the speed curve are scaled. Have a look at the speed curve in Fig. 26. The last entry (CV 94) is 255. This represents full speed. If you wish to reduce the maximum speed you only have to reduce the value of CV 5. The decoder computes (squeezes) the speed curve in such a way that the shape of the speed curve remains despite the lower maximum speed. The same is true for the first entry. The speed curve will be raised and scaled subject to the value in CV 2.

Setting each CV from 67 to 94, you should be able to define any speed curve you like, in spite of not being able to set a mid-point.

I seem to have reached quite an acceptable set of values for everything now; I can drive the engine more or less as I would like to, even though that means using much higher numbers from the 128 speed steps than I am used to for other locos.  If I find the time, I might look at redefining the speed curve by setting the steps from 68 - 93 one at a time.  It would take a long time though because of all the trial and error along the way.

If it's of any interest, I've experimented with a graphite 6B pencil at the places where the loco was jerking, and I think it's much better!  I took note of the warning elsewhere on RMWeb to use only a minimal film of graphite (" if you can see it, you've used too much") but the Mogul is now running consistently smoothly through my pointwork.  I'll post a video sometime in the next few days.
 

I spent an hour or two tweaking CV's on my Mogul yesterday (Loksound V5L).  Most of the changes were to do with acceleration and deceleration within the practical constraints of my layout.  I needed the loco to be capable of reaching a plausible running speed by the time it exits the tunnel mouth at the entrance to the storage table, and to be able to slow down in time for a stop at the platform.  I think I've achieved those goals now, though it meant resetting the wheel/chuff synchronisation.  I fiddled around quite a bit with CV54 (Back EMF - I think) but ended up doing the procedure that lets it set itself;  set CV54 to zero, press Function 1 and let the loco shoot off and then stop.  It ended up on a value of 43 this time.
I notice your rolling road not supporting the centre drivers:  when I was running my loco in, I was a bit concerned that the centre drivers would be able to oscillate a bit because they have a degree of springing.  I don't have  a rolling road, and ended up with the loco propped up a bit at each end and ran it in at a very gentle speed to avoid the centre drivers jumping up and down too violently.
The only slight fly in the ointment now is, as I 've said in my earlier posts, I think the loco is susceptible to dirty track.  It doesn't stall but it will jerk forwards a bit occasionally on pointwork that causes no problems for other locos.  My layout is in a shed and I think the very damp air in the evenings, before the shed has had a chance to warm up may be part of the problem.   I've been very interested to read of people using graphite sticks to give a very slight film on their track and achieve very reliable running, but I am a bit wary about potential damage to the vulnerable nylon gears on this loco.
 

I'm trying to figure out what vehicles might be included in a minimum length GWR permanent way maintenance train around 1946.  One end of my layout, "LLanidris" has trackwork terminating in flood damage and a bridge that has been weakened by flooding.  This never ending problem for the PW team seems like a good excuse for a train 
The question is; would such a train ever have been as minimal as a loco, brake van, 4 wheel carriage for the workers and one other vehicle for materials and tools?

24 minutes ago, GWR57xx said:

 

Hi @Stringfingerling, I've been following your trials on the other threads.

I don't think pickups is your problem - you said you had a Loksound 5L, which has built-in stay-alives.

Also the wheelbase of the tender is pretty much the same as that of this loco's drivers and any small tank engine.

Nice to know you found your main issue though - the Powercab momentum button.

Could the pointwork issue be back-to-backs or something else?

Cheers,

Peter

Hi Peter, 
You may be right - it's certainly true about the wheelbase of the tender. 
I don't think it's a back to back problem.  Most of the time the loco will run smoothly through the pointwork. When I first got the Mogul the pony track was under gauge and would hop slightly through the check rails, but a quick adjustment fixed that.  There is one very tight curve into my bay platform and the Mogul can manage it with a bit of a squeeze and I won't grumble about it not being completely smooth there, as it won't normally use the bay.   The rest of the pointwork seems to be no problem.
The reason I thought it might be to do with pickups is that I've noticed locos having different sensitivity to track dirt in the past.  I have a Tower Brass 14xx which is now about 11years old.  It literally never stalls.  The mechanism is a tad noisy but it's completely reliable.  My Dapol 14xx is beautifully quiet and smooth but does occasionally stall when crawling.  Naturally both  locos have identical wheelbases, though they are suspended differently and the pickup arrangements are different.  I wondered it was a question of some motors being able to keep going with a weaker current/higher resistance in the circuit to track?  I'm not expert enough to know the answer to that. 
The Mogul doesn't stall but it will occasionally jerk forwards while crossing pointwork at a crawl.  I'm guessing that when that happens the load compensation is noticing a sudden drop in Back EMF and compensates drastically until the BEMF is restored.  I'm not sure what influence the stay alive capacitor has.   I know track should be kept clean, but in the real world, I doubt if anyone cleans their track every time they want to run a train. 
It's not a major problem as the Mogul does run well now, but I have got used to my two Tower Brass locos - the other one being a 4575 which is smooth, powerful and also never stalls.
Thinking back to when I had decoders fitted to my Tower Brass locos, five years ago, I had various teething problems to sort out, including, neither loco working at all when they were first posted back to me from the shop that fitted the decoders.    It's been a bit of a thorny path into DCC land but when it works properly, it is very satisfying!
Cheers and thanks for your interest.
Rob

1 hour ago, Hal Nail said:

Let us know how you get on. I tried to get some Mogul spares before xmas and they told me they aren't selling parts until they have got them all listed and you can order online now.

I've had a bit of a struggle getting mine running properly in the last week since it arrived, partly because I didn't appreciate that I shouldn't be using the Momentum control on my NCE Powercab.   There are one or two threads on here explaining this.
To begin with, when I was testing on DC it locked solid straight away and it was easy to see that this was due to mechanical binding between the crosshead and (I think) the crankpin.  I tweaked the slide bars very slightly, as they appeared to be angled in a little bit and I think I've fixed that.  
I've climbed a major learning curve with my Powercab and CV's etc.  After using CV8 to reset the defaults  I think it's generally running very nicely, though I did lower CV54 to a value of 20 which, (I think) has made slow running smoother and I fiddled with the chuff speed to achieve four per wheel revolution.  
The issue I'm having now is (I think) due to sensitivity to dirty track, there are occasional stutters or jerks on pointwork.  It's worth me mentioning it because my other locos, which are all smallish tank engines don't do that.  I'm going to research whether people have successfully added pickups to the loco to improve this aspect.

11 hours ago, Albie the plumber said:

Going slightly off topic , I have to say I love that layout  can't fail to be impressed by it .

It must be inspired by the landscape around Bleanau Ffestiniog , even the sky has its typically moody , heavy look 

which is very refreshing !

 

Albie

Thank you Albie! Blaenau Ffestiniog is definitely part of the inspiration  though the story I have concocted for the layout centres round the fictional, but could have just about happened , standard gauge line along the route of the Corris Railway and beyond, in 1946.  I made a video a little while ago which you can  see here:

1 minute ago, Nigelcliffe said:

 

The PowerCab Momentum button *is* the explanation.  Reading down the thread, as soon as it became apparent that your changes had included using the momentum key, the answer was clear to me.   Paul put the link to his old thread explaining the dangers of the momentum key.   

 

The PowerCab momentum key overwrites the values in CV3 and CV4 in the loco.  Its doing programming-on-the-main of those two CVs, writing one of the pairs of values that NCE include at the factory.   There is no way of pressing the momentum button to return the loco to the original values in the sound project.   If the values in CV3 and CV4 are too low, then sound effects which are based on speed changes won't be registered in the decoder, so things like coasting will never be heard.  

 

There are four solutions:

a)  learn which momentum key settings give acceptable driving behaviour. 

b)  promise never to press the momentum key. 

c)  put a sticky-backed foam or rubber polo-mint ring around the momentum key to make it a bit harder to press without thinking

d)  physically disable the key inside the Powercab so it cannot be accidentally pressed.  

 

 

There is an option in the ESU decoder to change a number of CV's so a function key can turn off acceleration and deceleration.  That might be useful if you need to accelerate/brake hard in the storage areas.   If you don't have lights on the loco, then it could be allocated to the F0 (lights) key on the handset.  

 

 

- Nigel

Thank you Nigel. I'm very pleased to know what I'm  dealing with now. 

Once again, thank you very much Wiggy, Pauliebanger and others who have contributed to this discussion.  I think I understand the issues now.  The loco is behaving very nicely - I think it's just a question of not messing with the momentum button.  I had always assumed it was a "controller only" setting and I had no idea that it reset values on the decoder, as I hadn't run into issues with my locos, which, I think, all use Zimo chips.
I'll report back in a day or two in case people are interested - there are plenty of people with NCE Powercabs who might find themselves down the same rabbit hole as me.

Yet again, it's so good having a supportive community through RM Web.  I'm not a member of any club and I have any nearby modelling friends and on a number of occasions I've been offered ready help with problems that has proved invaluable.

This is an interesting thread on this subject that I had no idea about previously:

Here are videos 3 and 4.  As well as your suggestion above I've just been reading the linked post from Pauliebanger which might hold the key to this business.
Video 3, showing excessively fast acceleration/deceleration, even though the momentum control has been to a mid setting.
Video 4 after another CV8 reset showing coasting etc as expected. 
Tomorrow I shall try to get to grips with my NCE Powercab, so I can stop using the momentum setting in a way which  overwrites the project settings.   

Video 4 after reset of CV8
 

In between the first and second videos I've made no changes to CV's or anything like that.
I've just made two further videos which i'll upload in asap.  I set the momentum control on the controller to a mid setting (4) - there is no option to turn it off as far as I understand.  
The first of these  new videos- which I'll refer to as video 3 - shows how the loco behaves after this change on the controller. 
After filming that I then did a further CV8 reset and filmed the video 4, where the coasting facility has mysteriously returned.

Videos 3 and 4 will be posted in a few mins.

No functions switched on , but there is a "Momentum" setting on the NCE Powercab.  I normally keep on step 2-3 of 9, but I set it on 0 so that the loco would accelerate/decelerate as fast as the project motor acceleration settings would allow, so that I could get up to a reasonable speed fast enough to demonstrate how it was behaving when it slowed down.