Top & Tail DCC Driving

[Sails]

I have read snippets of threads where this gets mentioned, some thoughts on having the rear loco trailing only with drive gears disengaged/removed. Having sound muddys the waters more, but what are people doing if they want to run a T&T unit? There are so many options for this activity and with Hattons RHTT it really needs a T&T option.

 

Mark 

[jpendle]

There aren't any generic answers as the DCC controller and decoders really affect what you can do.

 

For my setup specifically, I use two powered diesels to top and tail my CMX track cleaner.

 

As I use a Z21, then no Decoder programming is needed at all.

 

The Z21 App allows users to add 'traction info' for each loco.

 

In the app you then add a 'Train' rather than a 'Loco'

 

In the 'Train' you add the two loco's you want to use.

 

You select the 'Train' in the app and the locos are speed matched and work perfectly whether double heading, top and tailing, etc,etc.

 

If you use a different DCC system then you'll probably have to fiddle with settings in your decoders to get this to work.

 

Now this is what I have seen here and in other places.

 

Sometimes it's better to use a Sprog 'with JMRI?' to program your decoders rather than your chosen DCC system throttle.

 

It can be very difficult.

 

BTW if you want to know more about the 'Traction Info' piece on the Z21 let me know.

 

Regards,

 

John P

[Ron Ron Ron]

I have read snippets of threads where this gets mentioned, some thoughts on having the rear loco trailing only with drive gears disengaged/removed. Having sound muddys the waters more, but what are people doing if they want to run a T&T unit? There are so many options for this activity and with Hattons RHTT it really needs a T&T option.

 

Mark 

 

 

You could have an unpowered loco, but it would reduce its usefulness and play time flexibility.

More commonly, most people would create a consist for the two locos in the T&T configuration.

That way, you can drive the individual locos into and out of the consist.

 

 

.

Edited December 7, 2018 by Ron Ron Ron

[Sails]

You could have an unpowered loco, but it would reduce its usefulness and play time flexibility.

More commonly, most people would create a consist for the two locos in the T&T configuration.

That way, you can drive the individual locos into and out of the consist.

 

 

.

 

Thanks Ron, I thought this would be the most sensible approach without the need to start having dummy locos at one end. The need  to run sound locos was a consideration for myself.

[ColinK]

An interesting question. I’ve all the items necessary to make a Glasgow - Edinburgh push pull set with a sound fitted class 27 at each end. If I keep both locos motored, I guess it will take some work to speed match them.

[Norm81]

I removed the motor from one of my pair of 20's, then they only have lights at the outer ends so are the same address too.

[Alan Kettlewell]

This is my own version of a Rail Head Treatment Train that operates on my continental layout.

 

I too use the Z21 and form the consist with the Train Controller software, The software does all the CV adjustments and speed matching that's necessary automatically as soon as I assign both locos to the group. Likewise on splitting up a group all settings are returned to each loco as individuals. It's aĺl quite painless, except for the cost of buying the software! But that's a whole other story. I hope you can come up with a good solution.

 

 

Cheers ... Alan

[tractor_37260]

An interesting question. I’ve all the items necessary to make a Glasgow - Edinburgh push pull set with a sound fitted class 27 at each end. If I keep both locos motored, I guess it will take some work to speed match them.

Interesting. Are your 27's fitted with Bif's matched pair of 27 decoders ? I've also got all the items necessary for a planned future project. I've found once 27's are well run-in it's fairly easy to speed match them, especially if you select 2 chassis that run similarily to start with.

[Paul80]

Hi

 

Only got two trains formed with two power cars, a Midland Pullmann and a couple of 68's on Nuclear Flask duty, both have Zimo Sound Decoders at front and standard Zimo decoders are rear, I found it quite easy to speed match them, the only issue being the sound decoders have a delay on starting to allow for the motor sound to rev up, and that was not easy to replicate and was told by the sound producer it's easier to disable the function on the sound decoder than to replicate it on the non sound decoder, although to be honest its that big an issue and with the back one starting first is not too noticeable or giving any real issue.

 

Paul

[letterspider]

On 07/12/2018 at 23:04, Alan Kettlewell said:

This is my own version of a Rail Head Treatment Train that operates on my continental layout.

 

I too use the Z21 and form the consist with the Train Controller software, The software does all the CV adjustments and speed matching that's necessary automatically as soon as I assign both locos to the group. Likewise on splitting up a group all settings are returned to each loco as individuals. It's aĺl quite painless, except for the cost of buying the software! But that's a whole other story. I hope you can come up with a good solution.

 

 

Cheers ... Alan

 

I find the idea of the Z21 balancing the consist very interesting.

HOw well does it cope with long trains running up and down gradients?

[jpendle]

1 hour ago, letterspider said:

 

I find the idea of the Z21 balancing the consist very interesting.

HOw well does it cope with long trains running up and down gradients?

Hi,

 

It works very well. I model in N Gauge but I have 2 Dapol CL86's double heading a long intermodal rake with loaded and unloaded wagons and it copes well with the gradients on my layout.

You must make sure that both locos are thoroughly run in before timing them and entering the traction settings though.

 

Regards,

 

John P

[Alan Kettlewell]

1 hour ago, letterspider said:

 

I find the idea of the Z21 balancing the consist very interesting.

HOw well does it cope with long trains running up and down gradients?

 

A good answer above from John P and directly addresses your question.  I could not answer this in regard to the Z21 as I dont set up consists with it.  My consists are set up up by Train Controller so it's the software that setsnup the CVs and does the consist controlling and not the Z21 directly.  I can say that control on all ascents and descents is faultless, subject to all DCC decoders being BackEMF enabled.  I have a few double headers pulling 8 coach trains and equivalent length goods trains, all flawlessly.  

 

Cheers ... Alan

 

[Michael Hodgson]

On 07/12/2018 at 23:04, Alan Kettlewell said:

This is my own version of a Rail Head Treatment Train that operates on my continental layout.

 

I too use the Z21 and form the consist with the Train Controller software, The software does all the CV adjustments and speed matching that's necessary automatically as soon as I assign both locos to the group. Likewise on splitting up a group all settings are returned to each loco as individuals. It's aĺl quite painless, except for the cost of buying the software! But that's a whole other story. I hope you can come up with a good solution.

 

 

Cheers ... Alan

 

 

 

This prompted an idea  ... a friend of mine with a course scale 3-rail O gauge layout, has an unorthodox way of  cleaning his track with his analogue electrical system.  This may seem crude but it is effective.

 

As with DCC, 3-rail DC control means that when locos face the opposite way round they run in opposite directions.  So he couples 3 similar heavy 0-6-0 locos, 2 chimney first the other tender first.  The two going forward are powerful enough to drag the third one with its wheels spinning which polishes muck off the rails.  This isn't exactly quiet!

 

To clean the stud contacts in the centre, he does use a special wagon, this has a file bent upwards at its ends mounted like a pick-up skate under the wagon which contains a great of of lead for adhesion.

 

Any thoughts on whether his approach  would be an effective method to adopt in OO/HO under DCC consisting, obviating the need for a special track cleaning wagon?  Locos with traction tyres would be inappropriate.

[Phil Bullock]

17 minutes ago, Michael Hodgson said:

 

 

 

This prompted an idea  ... a friend of mine with a course scale 3-rail O gauge layout, has an unorthodox way of  cleaning his track with his analogue electrical system.  This may seem crude but it is effective.

 

As with DCC, 3-rail DC control means that when locos face the opposite way round they run in opposite directions.  So he couples 3 similar heavy 0-6-0 locos, 2 chimney first the other tender first.  The two going forward are powerful enough to drag the third one with its wheels spinning which polishes muck off the rails.  This isn't exactly quiet!

 

To clean the stud contacts in the centre, he does use a special wagon, this has a file bent upwards at its ends mounted like a pick-up skate under the wagon which contains a great of of lead for adhesion.

 

Any thoughts on whether his approach  would be an effective method to adopt in OO/HO under DCC consisting, obviating the need for a special track cleaning wagon?  Locos with traction tyres would be inappropriate

 

 

Speajing from experience with modern non steam models am not at all Sure the drive trains would cope for long.

 

Likely failure points are plastic gears. Cardan shaft pivot puns and the flywheel drive cup, many of which come loose without being exposed to this extreme treatment.

 

Metal geared Hornby Tin plate models are probably a bit more robust! 

[Michael Hodgson]

16 minutes ago, Phil Bullock said:

Metal geared Hornby Tin plate models are probably a bit more robust! 

 

They'd be Bassett Lowke actually and they are pretty solidly built.  They have conventional gearboxes rather than nylon worm drives.

 

I rather think you're right about plastic gears and cardan shafts in modern rolling stock.  But would the principle work as well in smaller scales, using say old "steamroller-wheel" Triang or Hornby OO?  Perhaps rather than putting chemicals or abrasives on the track, one might design a track cleaning car which has a pair of steel or nickel silver driving wheels motored in reverse?   

 

I wasn't thinking of trying this by the way, I have too many other jobs to do!

[letterspider]

1 hour ago, Alan Kettlewell said:

 

A good answer above from John P and directly addresses your question.  I could not answer this in regard to the Z21 as I dont set up consists with it.  My consists are set up up by Train Controller so it's the software that setsnup the CVs and does the consist controlling and not the Z21 directly.  I can say that control on all ascents and descents is faultless, subject to all DCC decoders being BackEMF enabled.  I have a few double headers pulling 8 coach trains and equivalent length goods trains, all flawlessly.  

 

Cheers ... Alan

 

 

 

Thanks - this is encouraging me to learn a bit more about DCC control. I have another question

All very well that you have maybe two different locos with different gearing and different chips - what if one has a sound chip and one does not -  there will be a delay in starting off - how does Train Controller cope with that?

 

Ade

Edited September 7, 2020 by letterspider

[letterspider]

On the topic of cleaning - I have a Centerline track cleaner. It's advantage is you can cut up Jey clothes and use them, get very good results with Iso propyl alcohol or methylated spirits. 3 or 4 circuits of the track is all that is required for another 2 weeks or faultless running.

[Alan Kettlewell]

30 minutes ago, letterspider said:

 

 

Thanks - this is encouraging me to learn a bit more about DCC control. I have another question

All very well that you have maybe two different locos with different gearing and different chips - what if one has a sound chip and one does not -  there will be a delay in starting off - how does Train Controller cope with that?

 

Ade

 

Hi Ade,

 

A good question.  With or without Train Controller that is always going to be a tricky situation as, I'm sure you're aware, the sound loco may delay pulling away whilst the non sound loco will want to get going straight away.  I have not actually tried it however it is possible to adjust CVs  so that one loco will require a higher starting voltage than the other.  Such a technique woukd require a lot of trial and error but there may be better answers than I can give.  

 

I think to get more info about DCC it would be better to head over to the DCC questions forum.  Fair warning though, you might get a sore head .. some of those threads can get highly technical - and controversial!  

 

Enjoy the journey though as there's a whole new world to learn about.

 

Cheers... Alan

 

Edit - oh we are in the DCC questions forum - doh..  Sorry.. but anyway, other threads will be worth a read too.

 

Edited September 7, 2020 by Alan Kettlewell

[Michael Hodgson]

On 07/09/2020 at 20:20, letterspider said:

- what if one has a sound chip and one does not -  there will be a delay in starting off - how does Train Controller cope with that?

 

Ade

 

That's a nicety I wasn't aware of.  So it's not just the price of sound decoders that is putting me off them now.

[Nigelcliffe]

On 07/09/2020 at 20:20, letterspider said:

 

 

Thanks - this is encouraging me to learn a bit more about DCC control. I have another question

All very well that you have maybe two different locos with different gearing and different chips - what if one has a sound chip and one does not -  there will be a delay in starting off - how does Train Controller cope with that?

 

Ade

 

If you select your non-sound decoder well, then its not an issue.  As an example, ESU LokPilot V4 (non sound) decoders have a delay feature which can be used to match the delay in an ESU LokSound V4 decoder.   

 

Or, you can alter settings to change the starting delay in a sound decoder.   

 

Or, setting BEMF values appropriately will mean the loco will just stall until its able to move off.  

 

 

If adding control software, then no reason in principle why software cannot delay instructions.  

[letterspider]

Well in that case it looks like there is at least one solution not cheap though.

 

In this case a couple of TTS chips upgraded with good speakers starts to look attractive - for example using two older 8 pin Bachmann 37's - hmmm.

 

I am surprised manufacturers didn't give this a lot of consideration - it is not as if trains with multiple powered locomotives are a rarity - in any country.

 

 

 

[letterspider]

What is a Fleischmann Tachowagon?

 

http://cs.trains.com/mrr/f/88/t/84331.aspx

[Dungrange]

12 minutes ago, letterspider said:

What is a Fleischmann Tachowagon?

 

http://cs.trains.com/mrr/f/88/t/84331.aspx

 

A picture of said wagon at https://www.reynaulds.com/products/Fleischmann/5555.aspx

 

Basically, just measures the speed of the wagon from the revolutions of the wheels.