RTR Small Shunting Engines, Flywheels, and DCC Stay Alives

[cctransuk]

41 minutes ago, Ruston said:

No, it doesn't.

 

I see. Your point, coming from your experience as a novice to tracklaying and operating a layout, over-rides my experience (my ill-informed rubbish, as you call it) as someone who has built around a dozen layouts, and who uses almost exclusively extremely short-wheelbased models of tiny steam locos on both DC and DCC, does it?

 

The thing here is that as a luddite who clearly wants nothing to do with DCC, I don't know why you're involved here at all. If you read my previous posts, including my reply to RapidoTom, you will see that what I am calling for is the provision for DCC Stay Alives, not the fitting of. That means a space in which to fit one. The great thing about a space is that its empty. If a manufacturer designs this space into the model we can fill it with whatever we want. I would fill it with a Stay Alive. You can fill your space with whatever you want to give you this extra traction that you so desire; lead, brass, uranium - I really don't care. The point here is that as a DC user it doesn't affect you, so why you have to make all this fuss and tell everyone how they don't need something that you have no experience of using I do not know.

 

You don't have a sense of humour at all, do you, John?

 

 

 

This somewhat tedious (to others) exchange of views has been taken off-line.

 

CJI.

[D9020 Nimbus]

All I can say in my experience is that DCC and DCC silent 0-6-0T and 0-4-0T locos will pass over the dead frogs on the Fleischmann Profi-Track points in my test track at a crawl. But on DCC sound fitted locos the sound stutters on doing so. As a result I won't purchase a sound fitted loco with such a wheel arrangement unless said loco has a stay-alive. European manufacturers seem to have no problems with this, so what's different about Britain?

[Gilbert]

27 minutes ago, D9020 Nimbus said:

All I can say in my experience is that DCC and DCC silent 0-6-0T and 0-4-0T locos will pass over the dead frogs on the Fleischmann Profi-Track points in my test track at a crawl. But on DCC sound fitted locos the sound stutters on doing so. As a result I won't purchase a sound fitted loco with such a wheel arrangement unless said loco has a stay-alive. European manufacturers seem to have no problems with this, so what's different about Britain?

This has been the basis of my posts throughout. Essential (and entirely transformative) for small locos...

Chris

[Phil Himsworth]

Given it sounds like continuity of sound is a bigger problem than continuity of movement, can you get very small stayalive units that will fit in the smallest of locos which provide just enough power to keep the sound running but don't try to power anything else?

[Izzy]

11 hours ago, Phil Himsworth said:

Given it sounds like continuity of sound is a bigger problem than continuity of movement, can you get very small stayalive units that will fit in the smallest of locos which provide just enough power to keep the sound running but don't try to power anything else?

If you are prepared to make up your own stay-alive packs, which quite a few such as myself do, then the capacity can be tailored to suit what you either want, or can fit in the available space. For me, mainly working in 2mm these days, finding the space is the challenge. 
 

This can be done using Tantalum capacitors of either 16v or 25v plus the appropriate electronics I.e. resistor and diode ( for the charging circuit), and zener diode for 16v ( to prevent over-charging). All these parts can be sourced from DCC suppliers such as YouChoos or via ebay etc. There are also ready made PCB charging boards to which you just add the capacitors.

 

So stay-alive amounts can be from just a single tantalum of say 220uf to multiples of this, 440, 660, 880 and so forth.  Just enough to keep the wheels turning a bit and prevent the sound dropping out over bits of dirt or dodgy current collection caused for whatever reason. You can’t choose one or the other it’s just a way of providing a bit of backup power. As has been said the difference is quite astounding. All my smaller locos with less than 8 wheel pickup now use them, in 7mm/4mm/2mm scales. 
 

It’s worth noting that some decoders, Zimo that I know of (Idon’t use any other these days), often now have a small amount of stay-alive capacity ‘on-board’, particularly sound ones. 
 

Bob

[CF MRC]

I have used coreless motors in 2mm scale locos for over 40 years. The advantage of having little inertia and no magnetic lock is that a flywheel exerts a maximum coasting effect.  A decent controller (e.g. Pentroller) helps as well.  Continuous running under load is not an issue with these motors (at least not on CF). Haulage ability is also improved because there is less vibration. 
 

Tim

Edited December 11, 2022 by CF MRC

[Allegheny1600]

On 08/12/2022 at 16:49, D9020 Nimbus said:

All I can say in my experience is that DCC and DCC silent 0-6-0T and 0-4-0T locos will pass over the dead frogs on the Fleischmann Profi-Track points in my test track at a crawl. But on DCC sound fitted locos the sound stutters on doing so. As a result I won't purchase a sound fitted loco with such a wheel arrangement unless said loco has a stay-alive. European manufacturers seem to have no problems with this, so what's different about Britain?

Indeed!

 I have a Roco Bavarian 0-4-0T with sound and it will drive over my friends Fleischmann Profi track at normal to slow running speeds with no problem. I haven’t tried it at a crawl though but then, it’s not the sort of engine to do any crawling.

Unlike this model; Roco BR335 picture.

I’m sorry, I can’t insert the picture exactly where I want it.

This is a Roco BR335 diesel shunter of a B (0-4-0) wheel arrangement in H0 scale and comes ready fitted with sound, digital couplings and stay alive. You can see clearly how long it is, you can’t tell but it is quite heavy and still fits in all these electronics so I have had it pulling a dozen modern wagons along level track with no problem.

The stay alive is so effective that with the sound and all lights running, I can lift it off the track and box it up and as the lid goes on, sound is still going!

Oh, and it sounds like the real thing too.

 

[Ravenser]

Without wishing to restart an argument between two members, some relevant posts from another very long thread, where they are in danger of getting buried.

 

On 29/01/2023 at 12:39, Roy L S said:

 Hi Ben

 

If I recall correctly from my daughter's layout many years ago that used Fleischmann track (including a curved point), the frog is dead but there is a pickup strip down in the flangeway and continuance of current collection relies on flange contact. Therein lies the issue - fine flanges on the Hunslet very likely means no contact.

 

Just a reflection on Les's comment, I think people do have to be realistic about "stay alive" in such tiny locos, it will help prevent stalling resulting from momentary power interruption like dirt but it won't keep the loco running several inches as may be the case with bigger capacitors in the larger scales. The best solution I feel still remains to have as many wheels picking up over the longest footprint possible. A case in point is my sound fitted black 08 below (my conversion and pre-dating the new Farish sound fitted models) this employs a permanently coupled shunter's wagon wired for pickup meaning 10 wheels picking up over a wheelbase that doubles that of the 08 alone. It is almost never gets "gapped" and slow running/sound is very reliable.

 

Translating to the Hornby TT120 08 in particular, maybe a plug-in match truck as an option (like their OO Ruston 48DS) would help it with the dead frogs especially on their own brand track, in particular as regards any sound option?

 

 

Regards

 

Roy

 

On 29/01/2023 at 15:51, Les1952 said:

 

The dead frog itself isn't an issue with most locos, but the switch blades are rather relaxed as there is no centre spring to hold them over.  The problem is that on some points once the loco is sitting on the switch plade assembly its weight causes enough movement to cut the power to the blade.   All short wheelbase locos have the same problem.  Fleischmann have contacts built into the bottom of the frog which the wheels are supposed to contact- finescale wheels have flanges that don't touch these.  Hopefully this photo of one of Bregenbach's points under repair will explain the construction of the thing.  Sorry I haven't one without an overhead wire in the way.

 

Hope this helps.  Bregenbach uses Fleischmann track as Peco doesn't have the geometry to make the layout work and my preferred option of Tomix was unavailable due to lockdown.  The layout is at the N Gauge do at the NRM in May if you want to examine the offending points more closely.

 

Returning to TT, once the Scotsman set arrived I looked at the point and compared it with the Peco ones I had already got.  The length of the Hornby dead frog is horrendous, the sound-fitted 08 will need quite a large stay-alive top keep going, and I have serious doubts as to how slowly the analogue ones will run through Hornby points.  My smallest loco for Bregstadt will be an Arnold Kof, a 4-wheeler with a short wheelbase.  With Peco points it has a chance of running very slowly through them.

 

Les

 

 

 

[Ravenser]

Just now, Ravenser said:

Without wishing to restart an argument between two members, some relevant posts from another very long thread, where they are in danger of getting buried.

 

 

 

 

 

Now for some comments of my own:

 

A good many years ago I was involved in a club layout project which ultimately failed, about 18 months after I dropped out. Originally the project was to be DC and we were introduced to a gentleman whom it was suggested would be suitable to be our "sparks" . He wanted to specify not just a dropper to every rail , but 2 droppers per piece of rail , for complete reliability in case a dropper failed due to dry joints, wires snapping etc.

 

He drifted away before things got properly going, the layout went DCC - but we still went with 2 droppers to every longer bit of rail and one dropper to the short ones.

 

When I built  Blacklade , I carried on with the same standard, and from memory I tried to use "3 amp" wire, soldered underneath the rail, to eliminate any risk of voltage drop (we had an issue on the corner board of the club project where there seemed to be voltage drop, and some of the droppers were running at 3' to 4' run)

 

So Blacklade has massive electrical feeds and is probably very much over-engineered in this area.

 

This still doesn't eliminate all risk of stalling. Anything with all wheel pickup from two bogies is fine and runs entirely reliably.

 

But the two home-made diesels , powered by 5 pole Hornby Ringfields with traction tyres but pickups to all wheels (effective 6 wheel pickup) are known to stall and need prodding occasionally.  Baby Deltic  .The detailed Lima 37 (also 6 wheel pickup) is a little better but not perfect.  In an effort to mitigate the stalling I swapped out the wheels on the unpowered bogie for Bachmann coach wheels which have shallower flanges , and this helped.

I did the same on the NBL Type 2 : D6103  Neither is totally stall-free and I am toying with the idea of ordering a budget pack of double-motor Ultrascale wheels and rewheeling the power bogies on both.

 

Given that each bogie is electrically an 0-4-0T , I'm sceptical of the claim that provided you have a dropper to each rail there will never be issues with 0-4-0s stalling...

 

Why didn't I fit stay-alives? Well, I would have liked to, and there is bags of room inside both locos. I even managed to source a Lais stay alive, and I have a couple of DCC Concepts ones going spare . But - it wasn't at all clear that a Lais stayalive will work with anything other than a Lais decoder. And all I have is a capacitor with wires and no instructions. Certainly hard soldering is going to be required - not necessarily an issue in itself , but I've no real idea what I'm supposed to be doing with it....

 

In short stay-alives recede into the mists of dark arts /esoteric knowledge , like a will o' the wisp. "Here, kitty, kitty, kitty..."