OO gauge GWR Mogul and Prairie

[tomparryharry]

I guess both you & I are honourable members of the DC luddite Brigade.  Manufacturers take a pragmatic view that a model needs to 'cover all the bases' so whether you like it or not, the model will be sold with an ability to accept the knick-knacks that we wouldn't normally use. 

 

Perhaps we need to develop a set of moulds to create the extra weight, in lieu of the space taken up by the redundant gizmos.    

[Oldddudders]

16 minutes ago, melmerby said:

I thought decoder and speaker in the tender was the best way to do it.

There is no reason why a "easy fit" decoder can't be under a removable coal space.

Sticking it in the smokebox is so "DJ Models"

Decoder in the tender requires cabling between the two parts of the loco - tender-drive only excepting! I have read complaints about that on here, with people finding the plug and socket a challenge. Having dealt with my first in 1999 - a Bachmann HO 2-8-0 to which I fitted sound - I have learnt to live with them. And if the speaker is in the tender, too, I have read comments that most loco noises come from the front end. But if you put the speaker up front and the decoder in the tender, that's now six wires between loco and tender. 

 

I do not deride the DC brigade, and never will. DC worked just fine for everyone for decades. It still does so today. 

[No Decorum]

1 hour ago, melmerby said:

 

I thought decoder and speaker in the tender was the best way to do it.

 

I’d agree with that. The problem is with tank locos. One manufacturer seems to have decided to use the dreaded (by me) coreless motor to save space for the gubbins in them. The Next18 seems a nice and compact decoder, in particular, it and its socket are nicely flat. What I would like to see are tank locos with Next18 sockets, space for a speaker, preferably included*, a compact traditional motor and the tanks packed with ballast. I think that is either achievable now or will be before long, judging by how compact some traditional motors are these days,

 

*Note to DC fans: a pre-fitted speaker is reported not to cost much.

1 hour ago, Oldddudders said:

 

I do not deride the DC brigade, and never will. DC worked just fine for everyone for decades. It still does so today. 

 

Nor will I. Even though I’m a “sound fanatic”, most of my cherished little machines are DC and my layout is “bilingual”.

[The Johnster]

I agree.  The fitting of motors that are not large enough is common, and often referred to by the likes of Tony Wright who comment that RTR pacifics are not capable of doing the work of real ones while his kit built ones are; we are talking about heavy 14 coach expresses at scale speeds in the 80s here.  Tbh it is less of an issue on my small, level, BLT where the heaviest train is an 11-wagon and a van loaded mineral that can be handled by all my locos (though some can be made to slip a little with rough driving).  Slow running and smooth stops and starts are more important to me than scale top speeds and loads. 

 

If a motor does not develop enough power to do the work at low speed, then it must be made to run faster, increasing the RPM which then has to be geared down to the final drive ratio with extra gearing, which takes space that would be better used for ballast and is likely to diminish low speed smoothness with added drag and friction.   The manufacturer in China is probably unaware of the issues, and will source motors that are easily available and of proven reliability without concerning himself with their suitability or otherwise for the model's actual use on our layouts, and you can't really blame him; he's doing his best which is by and large pretty good for the price!

 

The ideal motor for any loco (assuming we are talking about a 'normal' can motor aligned lengthways on the chassis and hidden in the firebox to preserve cab detail and under-boiler detail and sight lines for visible daylight) is the biggest that can be fitted and develops the most torque at low revolutions, but the ideal is unlikely to be avaialble or pursued by the manufacturer who has manufacturing to get on with.  Things have improved since the 70s and 80s, mind, when the normal motor was a feeble pancake that ran at very high revs to develop any useable power at all and then lost that advantage through spur gears, and had to resort to traction tyres, Satan's snot, to pull trains.  They were awful and I'm glad we no longer have to put up with them!   The one in the Mainline mogul (and the manor) was so big it necessitated fattening the firebox, a major fault on those models; at least Dapol have circumvented that problem...

 

DCC whistles and bells also take space which could be IMHO better used for ballast or bigger motors, and while I was once a big fan of flywheels, I am now dubious about their benefits at low speeds and voltages; they are of limited use to me on a small BLT where locos don't get to stretch their legs.  My locos are all tank engines, and space is limited in the smaller ones; I have 'hard wired' them direct from the pickup strips to the motor terminals so as to be able to dispense with the 'DCC ready' chip and free up more ballast space.  Many manufacturers do not exploit the space they have fully IMHO, with voids often being left in smokeboxes, bunkers, and inside tanks.  These voids are no doubt useful for fitting DCC speakers, servos, and wotnot, but I fill them with ballast, which as I have said never does any harm.   I doubt I could overload any of my locos  with ballast to the extend that they were incapable of running, unless I had access to collapsed star material or unobtainium, though it might be possible in the cavernous boilers of Tony Wright's pacifics!  

 

Traction and smooth slow runnin is not just a matter of power and gearing; it is also affected by the tracklaying, as anything less than perfectly level track smoothly joined to the next piece will tax the abibilty of the rigid block chassis to keep all the wheels in contact with the rail head.  If any such contact is compromised, slow running, pickup, and tractive effort are compromised with it.  The answer is fully compensated chassis, but the cost for it's provision to a standard that will ensure reliabllity in a volume produced RTR model is always going to be prohibitive; many RTR loco compromise with sprung axles and built in sideplay, but if an axle goes out of level transverse alignment, very precise amounts of play in every joint in the motion are required to prevent the chassis binding while preserving clearances on tight curves.  This will be the bane of those layout owners who rely on setrack geometry to be able to fit their layouts into limited spaces and still want to run long wheelbase express or heavy freight locos that the manufacturer states are capable of running on such geometry.  They are, but need everything else to be favourable as well.

 

 

[The Johnster]

Maybe it's time for a review and critique of control systems.  DCC has gone from strength to strength since the days of Zero 1, but the fundamental tech has not altered in that time while having all sorts of bells and whistles bolted on to it, most of which I am not much more than barely aware of.  There are NFC technologies that might serve us better than DCC as it currently stands,  Meanwhile, back at the DC ranch, nothing much has happened in 40 years; the state of the art is still the Gaugemaster, which still works well enough. but I am dismayed that no work has been done to improve on it, and that train set controllers are still of pretty low quality. 

 

A DC stayalive would be a most useful device, but I accept that on a system that depends on reversing the polarity of the feed to enable trains to run in both directions prevents it, at least according to my limited understanding of what diodes and capacitors do, and the results of my experimentation with a Lima 94xx chassis back in the ealry 90s.   A constant poloarity feed with the reversing carried out by circuitry aboard the loco might work.

 

 

[Chuffer Davies]

30 minutes ago, The Johnster said:

  A constant poloarity feed with the reversing carried out by circuitry aboard the loco might work.

 

 

That has been available since the 1950's from Marklin (3 rail only), but I can only assume that it was not universally liked because it never became more widely adopted.  ..... 

 

I think what you are suggesting is effectively what DCC delivers.  The DCC track feed I believe is AC but the power supplies are DC so there must be some jiggery pokery ging on iin the command station to convert the DC feed back to an AC supply to the track.  No doubt an electronics expert could explain how and why DCC does this.

 

An alternate method might be some kind of remote control system and there is a system currently being developed commercially.  This system promotes the use of batteries but I see no reason why the power couldn't come from the track instead.  

 

In reality we are spoilt for choice but train manufacturers have understandably stuck to the two most popular systems of DC and DCC and leave it to the dedicated hobbyist to implement any other system they might chose for themselves as well as absorbing the costs associated with them.

 

After all, in the end it is all driven by cost v's benefit as in any other type of business.. 

 

Frank       

[melmerby]

The DCC signal is both an AC supply for an on board power supply unit on the decoder and carries the DCC signals that the decoder needs to produce the command desired.

The waveform used for DCC is effectively a square wave but where the mark-space ratio is varied and these variations translate into digital "1"s or "0"s.

The pattern of ones and zeros determine the code being sent to the decoder.

All the motor control is carried out by the decoder.

 

Edited December 1, 2020 by melmerby

[The Johnster]

Just ordered Hornby large prairie in lieu of 94xx for xmas pressie to myself, and as I will have no further interest in the developement of the Dapol large prairie or it's mechanism I will hereby bow out of contributing to this thread, which has been informative and instructive and which I have enjoyed participating in.  Thank you for your responses to my input, ATB.

 

 

[melmerby]

2 hours ago, The Johnster said:

 

 

A DC stayalive would be a most useful device, but I accept that on a system that depends on reversing the polarity of the feed to enable trains to run in both directions prevents it, at least according to my limited understanding of what diodes and capacitors do, and the results of my experimentation with a Lima 94xx chassis back in the ealry 90s. 

 

 

IIRC a DCC decoder fitted loco will go the correct direction when fed with DC (if DC is enabled), so a stay alive on a DCC decoder should work.

[Izzy]

I'm afraid I am not really sure why, but with quite a few decoders switching off DC running capabilities is needed when a stay-alive is fitted, and recommended is done with all decoders even without for more consistent/reliable running on DCC - the prevention of runaways etc.

 

I know that you are supposed to be able to run DCC fitted on DC but the odd few times I have tested it, the results have been, how shall we say, underwhelming.

 

Izzy

[autocoach]

Batteries can add substantial weight for dead rail to get around the conundrum. Wi-Fi or Bluetooth communication for control means  no rail connectivity required.  The Wi-fi installation I recently did included speaker and onboard chip for software upgrades and alternate sounds.  Still using track for power from existing DCC system at this stage but next year will add batteries to tender locomotives and multi-unit diesels with batteries in dummy units.  I use an inexpensive Amazon Fire tablet for the throttle software connecting through my house Wi-Fi. 

 

I expect in about 2-3 years the dead rail option will gain sufficient technical support that it will be competitive with DCC. 10 years from now only troglodyte wiring masochists will use rail powered let alone rail signal or voltage controlled locomotives.

 

The Dapol GWR mogul tender looks like it could house a small size battery system for 30-45 minutes of continuous running at the current level of battery technology (pun intended.) A plug charging system through the removable coal load and you would have to simulate real operating conditions where the locomotive is serviced every few hours for water and coal.  Cable between tender and locomotive can be disguised as the tender water connection. 

Edited December 1, 2020 by autocoach

[melmerby]

25 minutes ago, Izzy said:

I'm afraid I am not really sure why, but with quite a few decoders switching off DC running capabilities is needed when a stay-alive is fitted, and recommended is done with all decoders even without for more consistent/reliable running on DCC - the prevention of runaways etc.

 

I know that you are supposed to be able to run DCC fitted on DC but the odd few times I have tested it, the results have been, how shall we say, underwhelming.

 

Izzy

Re. stay alive, I hadn't seen that you should switch off DC capability, having never needed one.

Maybe someone could try and see whether they willm work with DC enabled.

 

I have tried a loco on DC and it worked OK. (nothing special)

I do routinely turn off DC running though when I fit a decoder.

[melmerby]

23 hours ago, Budgie said:

I weighed mine (loco only) and I'm afraid to say it's 210g, hence my wanting to add 100g.

Blimey

That is light, there must be loads of fresh air in there.

[David Stannard]

Well I finally received my copy of 6385 today and will say it is a beautiful model that stands well and above the previous incarnations, that said it does not have the outside steampipes as per the real life locomotive for the era that is supposed to be representing which is rather disappointing.

[JSpencer]

11 hours ago, autocoach said:

Batteries can add substantial weight for dead rail to get around the conundrum. Wi-Fi or Bluetooth communication for control means  no rail connectivity required.  The Wi-fi installation I recently did included speaker and onboard chip for software upgrades and alternate sounds.  Still using track for power from existing DCC system at this stage but next year will add batteries to tender locomotives and multi-unit diesels with batteries in dummy units.  I use an inexpensive Amazon Fire tablet for the throttle software connecting through my house Wi-Fi. 

 

I expect in about 2-3 years the dead rail option will gain sufficient technical support that it will be competitive with DCC. 10 years from now only troglodyte wiring masochists will use rail powered let alone rail signal or voltage controlled locomotives.

 

The Dapol GWR mogul tender looks like it could house a small size battery system for 30-45 minutes of continuous running at the current level of battery technology (pun intended.) A plug charging system through the removable coal load and you would have to simulate real operating conditions where the locomotive is serviced every few hours for water and coal.  Cable between tender and locomotive can be disguised as the tender water connection. 

 

For me, this would not be practical for an exhibition.

Exhibitors : "Excuse me mate, can I have the WIFI code for the hall?" 

Organisers : "there is none"

Or worse, everyone using the same wifi at the same time, sometimes controlling each others locos in error!

Bluetooth is such a pain. It takes ages just to connect the phone to the car and heaven forbid that both me and my wife's phones are in bluetooth range at the same time (who would have thought bluetooth can cause marital disputes?).

 

Batteries - I try to avoid them. Nasty things full of polluting toxins. If you think Mazak rot is bad, wait for batteries to start eating away your loco. Those poor collectors leaving things in  boxes for years finding all their locos ruined by battery acid.

45 minutes is not enough for an exhibition neither.

It gets a bit complex trying  to add these to small highly detailed tank locos too. I am not sure I would want a battery van permanently coupled to each of my shunting engines.

It might the future of kids toys with cheap plastic track but I rest skeptical that it will replace live rails. 

 

 

Edited December 2, 2020 by JSpencer

[Chuffer Davies]

8 hours ago, melmerby said:

Blimey

That is light, there must be loads of fresh air in there.

If you refer back to the pictures I posted :

you will see that the chassis almost completely fills the space available within the moulded body.  There is a small void in the smokebox but this is used to house the DCC connector so would only be available for ballast if the aDCC wiring regime was first modified to remove or relocate the DCC facility to the tender.

 

Frank

[spamcan61]

42 minutes ago, JSpencer said:

 

For me, this would not be practical for an exhibition.

Exhibitors : "Excuse me mate, can I have the WIFI code for the hall?" 

Organisers : "there is none"

Or worse, everyone using the same wifi at the same time, sometimes controlling each others locos in error!

Bluetooth is such a pain. It takes ages just to connect the phone to the car and heaven forbid that both me and my wife's phones are in bluetooth range at the same time (who would have thought bluetooth can cause marital disputes?).

 

You wouldn't use the hall WiFi, you'd use your own access point (say 20 quid); Bluetooth is the wrong tech in my opinion, never designed to be a 'one to many' protocol, unlike WiFi . Personally I'd go with very small removable batteries, almost like a 'stay alive' and have most of the track energised for charging  - apart from the difficult bits like points and crossovers. Having started looking at DCC it does look very 80s in terms of the 'tech' used but obviously there's a fair old installed base now.

[No Decorum]

1 hour ago, JSpencer said:

 

For me, this would not be practical for an exhibition.

Exhibitors : "Excuse me mate, can I have the WIFI code for the hall?" 

Organisers : "there is none"

Or worse, everyone using the same wifi at the same time, sometimes controlling each others locos in error!

Bluetooth is such a pain. It takes ages just to connect the phone to the car and heaven forbid that both me and my wife's phones are in bluetooth range at the same time (who would have thought bluetooth can cause marital disputes?).

 

Batteries - I try to avoid them. Nasty things full of polluting toxins. If you think Mazak rot is bad, wait for batteries to start eating away your loco. Those poor collectors leaving things in  boxes for years finding all their locos ruined by battery acid.

45 minutes is not enough for an exhibition neither.

It gets a bit complex trying  to add these to small highly detailed tank locos too. I am not sure I would want a battery van permanently coupled to each of my shunting engines.

It might the future of kids toys with cheap plastic track but I rest skeptical that it will replace live rails. 

 

 

Absolutely. Do we really want to have to plan our running sessions so that the necessary locos are charged beforehand? Much better to be able to just plonk a loco on the track and go. Do we really want locos which derail to carry on moving until they nose-dive onto the floor? (The same argument applies to stay-alives which have too much reserve power.)

[Dunsignalling]

On 01/12/2020 at 08:43, Izzy said:

The problem these days is the requirement to allocate space for decoders and speakers which eats into where weight could be placed hence the return to metal body parts and the - sometimes - fitting of motors that are too small for the purpose.

 

Izzy

Which is OK with me, I just chop out the DCC gubbins to make room for lead which is far more useful.

 

John

 

[melmerby]

13 hours ago, autocoach said:

 

 

I expect in about 2-3 years the dead rail option will gain sufficient technical support that it will be competitive with DCC. 10 years from now only troglodyte wiring masochists will use rail powered let alone rail signal or voltage controlled locomotives.

 

 

Dream on

Been on about this for years and progress is glacially slow.

Small locos such as tank engines definitely a no-no

N scale - no chance, there's barely room for what's needed now.

[melmerby]

1 hour ago, Chuffer Davies said:

If you refer back to the pictures I posted :

you will see that the chassis almost completely fills the space available within the moulded body.  There is a small void in the smokebox but this is used to house the DCC connector so would only be available for ballast if the aDCC wiring regime was first modified to remove or relocate the DCC facility to the tender.

 

Frank

Yes

Loads of space wasted on a decoder mount which could be in the tender.

All that could be metal.

 

Still hypothetical for me as Royal Fail still haven't delivered my Mogul from Derails

It was out for delivery yesterday but didn't come.

 

 

 

[Allegheny1600]

14 hours ago, autocoach said:

Batteries can add substantial weight for dead rail to get around the conundrum. Wi-Fi or Bluetooth communication for control means  no rail connectivity required.  The Wi-fi installation I recently did included speaker and onboard chip for software upgrades and alternate sounds.  Still using track for power from existing DCC system at this stage but next year will add batteries to tender locomotives and multi-unit diesels with batteries in dummy units.  I use an inexpensive Amazon Fire tablet for the throttle software connecting through my house Wi-Fi. 

 

I expect in about 2-3 years the dead rail option will gain sufficient technical support that it will be competitive with DCC. 10 years from now only troglodyte wiring masochists will use rail powered let alone rail signal or voltage controlled locomotives.

 

The Dapol GWR mogul tender looks like it could house a small size battery system for 30-45 minutes of continuous running at the current level of battery technology (pun intended.) A plug charging system through the removable coal load and you would have to simulate real operating conditions where the locomotive is serviced every few hours for water and coal.  Cable between tender and locomotive can be disguised as the tender water connection. 

That’s nice, add batteries to the tender means more weight that the loco struggles to haul around.

It’s already proven that people don’t like loco to tender connections.

Dead rail is just a dead end.

[tomparryharry]

2 hours ago, melmerby said:

Dream on

Been on about this for years and progress is glacially slow.

Small locos such as tank engines definitely a no-no

N scale - no chance, there's barely room for what's needed now.

 

So... T-gauge...?

[melmerby]

1 hour ago, Allegheny1600 said:

 

It’s already proven that people don’t like loco to tender connections.

 

So much so that I have converted three locos so that the decoder is in the tender and some lead is where the decoder used to be in the loco.

[Butler Henderson]

The issue with wires to the tender is doing them properly not with a mini plug that is too small for many to inset in awkward place or with wires on weak solder joints, both Hornby specialities