34theletterbetweenB&D

I see DCC as a utility, so want to pay the least cash for the desired performance. For me that's Lenz and Zimo, because I want truly smooth transitions in and out of movement, and accurate speed matching to meet my operational requirements, and it's mostly steam models they are fitted in. Truly, as some of the earlier replies suggest, you need to 'suck it and see' to determine which decoders deliver your requirements when used in combination with the traction you own. Do tell what you find with your latest purchase, from a brand which I have never heard of.

If tender pick ups were truly essential then no total adhesion tank loco would work reliably. Since 0-6-0 tank locos in particular are essential for steam era modeling, the best design principle is to develop expertise in obtaining the necessary pick up from the driven wheels. Bachmann's early wiper pick up steam loco product exemplified this, a very neat short wiper (nearly concealed behind the wheel) reliably delivering effective contact pressure, and the provision of at least one sprung driven axle. (And because the wheels are metal castings there is also conduction between the wheels by the coupling rods, which enables the party trick of their 9F which will run given power to the flangeless wheelset, which has no pick up wipers.) The sole justification for tender pick up is set track points with way oversize dead crossings - but this is a bodge to mitigate the effect of a poor track system.Personally I do away with tender wiper pick ups to reduce the drag these cause: Rapido made a good job of the Stirling single with pick up through the bearings on the tender split axle ends for no incremental drag: that's the superior method that should be employed.

All previous evidence suggests usage defeats 'correctness'. There are no rules for English; slong aswe unnerstan thass gud nuff.

The GPO's 'London Postal Railway' was a practical freight demonstration; and there are now defined routes specifically constructed for driverless passenger rail operation in the UK, starting with the Victoria line. And that's just the UK, bound to be many more. I recall DB proposing wagonfreight distribution by this method, freight terminal to rail served customer location.

If it is a lubrication issue, typically the locked wheels will be in random positions. If it is mechanical fouling causing the lock up, that's typically one or two positions only. Run the model to failure and collect the data is one approach. Or you might prefer to first go after the major vulnerability of outside cylinder steam locos : there is little clearance between the leading wheelset crankpins and the connecting rods. If the lock ups always start on curves per Johnster's suggested testing, that's what I would look for by inspecting while viewing from the underside.

That's the route whereby I acquired mine, on my first time around as a churchwarden. You have to know a good locksmith; wedding certificates among other essential items in a C19th safe...

But just right for Chigley. The contemporary primary school generation will be retiring fairly soon.

Two more plus points for graphite. Where it might be seen, it looks like authentic railway filth. As well as bogie pivots it keeps close coupling mechanisms functioning smoothly, especially helping moulded gangway faceplates slide smoothly in and out of contact. Screaming wipers or window rubbers, squeaking actuator among the controls, and the like on your wheels? Fixes those. (Of course you discover you need it whan 600 miles from home, but that's life.)

DCC is specified for 22V on track, or at least was the last time I looked. Your choice in making such a decision, but if your locos ever 'go visiting'...

There is proven superior technique in HO for those that must use set track. The wheels are flanged and run in an inside frame truck. The exterior frame re[presentation is a thin piece, hinged and moves out to accomodate the wheelset movement on the inside of the curve by contact with a projection on the truck frame, returning to correct position on straight track by spring action. Also 'wrong' but the best possible compromise I have yet seen.

There's plenty of choice in superior decoders, and not necessarily any more expensive ; all my OO steam models have a Lenz standard or Zimo MX6xx in them and perform beautifully.

K3 61800 -09 The ten from the GNR K3/2 61810 - 69, except 61863 rebuilt to K5 K3/3 61870 -89 K3/2 61890 -61992

Just my distant memory, but on early 1960's BR wagons the 'FIT' suffix only appeared consistently on the BR LOWFIT.

And yet further possibilities, the wire connections to the pick up wipers may have been exchanged by a previous owner, or the motor magnets were installed with poles reversed. .

I model ECML in the final years of steam, and that's what the wide firebox power, pacifics, V2s and BR standards, were regularly seen with; when on freight up to sixty wagons. The carriage and wagon stock is a mix of Bach, Hornby and kit builds, and the maximum train loads weigh about 2.5kg. Great attention is paid to ensuring free running, vehicles are not accepted into operation until they roll away when placed on a true 1 in 100. In this respect, Bachmann are the clear leader in RTR OO carriage stock, with pinpoint axle pick up bogies which will roll away on less than 1 in 200, they regularly detect gradients on notionally level track. Rapido's wagons with brass bearing inserts also, a good match to the 'originals' in 4mm, MGW's wheelsets which set the standard for my free rolling expectations well over 40 years past. The critical criterion for haulage is the capability to reliably start (and stop!) a 2.5kg train with the whole train on a 1 in 160. The Bach and Hornby wide firebox models can manage the load comfortably on level track as supplied, and among the more recent introductions: Hornby's Brit, W1 and P2 and Bachmann's 9F and V2, all will pull these loads on the layout gradients of 1 in 160. The Bach A1 2000 and A2 2010, Hornby A3 2005 and A4 2004 (production dates) have all had weight added as required, plenty of space within! The 2-8-0 models are all too light as supplied, with the sole exception of the Heljan O2, and require added weight. Weight is adjusted on all but a few of the narrow firebox tender locos to confer sufficient traction for their rating; of what I own it has only been Hornby's fairly recent metal body construction releases that do the job they are rated for as supplied. Tank locos are typically more than heavy enough, some could do with weight loss! I should like to sample the products of all the more recent brands now on the market, but they need to get going on dry side main line prototypes; thus far only (very satisfactory) tank locos, and none of the maximum power classes.

The 36-553 (8pin) and 36-554(21pin) were clearly different items from those in your pics. When introduced by Bachmann circa 2008 they were typically identified as badged ESU lokpilot v1 in online discussions. Whether that was a correct description who knows, unless someone commenting at the time can chip in.

I am pretty sure that this is the root cause of the problem in OO. The technique was designed for European HO, and the brand's offering this new capability made it very clear that the old hook and loop couplers had to go, and a rigid link between the coupler pockets was required. No such advice was offered that I can recall when Bachmann and Hornby introduced these mechanisms to OO. Not on the UK product - which may or may not be an optimal idea, but can be made to work very well. With the rigid Roco couplers my mk1s and Pullmans have the gangway faceplatesd in contact on straight track and open out for sufficient clearance on any curve radius that the individual vehicles will negotiate. I want to operate up to 15 coaches, and require scale separation of loco and tender on straight track. Now my recollection of the N class is about 22 years past, a late friend had one, and it regularly derailed its tender to the extent that he lost patience and we put in a plain drawbar - more on this anon. That looks more like the business. Now, when they get around to a B16, D34, J6 or K2 I will be pleased to evaluate that. And the final piece, most UK locos are that small that no camming action is required if the long established curve radii for an OO model railway are utilised. Nothing smaller than 24", and 30" as an absolute minimum if big engines are used, though 36" is what is really required. Surely no one uses set track any more?

As applied to bogie carriages it is fine, because the angular movement of the bogies relative to the long carriage body drives the camming action, restoring the vehicles to straight ahead alignment on eixiting curves. I was happy to see this feature introduced to RTR OO, having long seen it applied to good effect on my continental cousin's HO model railways, But there are no such bogies available on RTR OO steam locos, and even a bogie on eight wheel tenders - a relative rarity in UK practise - will do little to drive the required camming action, because the tender is so short so the angular movement of the bogie relative to the body is small. The only restoring action available is by means of a spring, which leads to your question: I would suggest that the answer is inappropriate application of this type of mechanism. (Lacking significant angular movement of bogies on both vehicles there is too little restoring force available. Attempting to overcome this with a spring is inadequate, as the tension has to match the train load to be effective. Apply sufficient tension to match the maximum load the loco can haul will result in derailment of the loco or tender when running with no load.) Thus my 'KISS' suggestion to Bachmann. What Bachmann have demonstrated with a rigid drawbar mounted in the loco on a pivot, engaging a pin on a concealed screw locked slide under the tender, enables user loco to tender spacing adjustment to suit the layout's minimum radius curve. Simple and proven to perform well in my experience of all their locos with this arrangement.

Done, it's been submitted 'down below' in 'Modelling musings' for the moderator to ponder if it is worthy of admission. And it has been approved so please make input there. Strike one, failure to resume the straight ahead alignment on coming off curves, and the heavier the train load the worse the effect. Strike two, spacing overscale, so falls short of optimum appearance even if it could be made to function adequately.

First seen on the Bachmann N class over 20 years ago and rapidly abandoned. and now making a reappearance on Bachmann, Hornby and (I am informed) Dapol product. If it worked as effectively as the camming close coupling mechanisms on Bachmann and Hornby carriages all would be well. But the simple fact is that it does not, the loco and tender remain skewed on straight track after exiting curves, and the more train load there is behind the tender the worse this effect becomes. Quite simply there isn't an adequate mechanism on a loco and tender to provide the required force to resume the straight ahead alignment; unlike carriages which have the bogie rotation relative to the carriage to actuate the camming action. I have written to Bachmann suggesting they ditch this 'feature' and revert to their neat rigid drawbar with a screw locked adjustment of loco to tender spacing, the best linkage in RTR OO to date. If any here feel the same pleas make your opinion known to the brand managements, or we will be stuck with this device...

No, the USA. The wide firebox began its development there well before M. Chapelon was pushed out of the womb. And in the UK context, the GNR. The introduction of the Ivatt large atlantic was the announcement here of the obselescence of the narrow firebox for maximum power steam traction. (Churchward clearly understood this, but ran out of road before his own response could be sufficiently developed.) While Col. Rogers does well, the yet greater eye opener is M. Chapelon's 'La Locomotive a Vapeur'; try your library service for access, unless you can find the English translation at a reasonable price. It's one of a very small number of regular bedtime reading books that I miss so much when away from home...

Yes, since Bachmann started using that in about 2010 it has been the benchmark. I wrote to Bachmann last July regarding the V2, suggesting they revert with immediate effect to this method. Polite reply received, and I would encourage others to similarly contact Bachmann.

Now you have provided the bigger picture, I undrstand why the vintage team could not supply a satisfactory answer.I am a long term mechanism tinkerer, and as soon as this path is taken you are effectively on your own, unless you can find others using exactly the same modifications, track system, and all the rest. That's product from decades ago, with plastic axles which were not resistant to all the potential lubricants that might be applied, among other problems. It might supply useful guidance, but then again it might not. What you have to do is characterise the wheelset for tyre and flange profile and dimensions, the most critical of these, from flange root one side to wheelback the other side which is the gauge for correct action of the check rails on the wheelsets, and is thus referred to as 'check gauge'. The famous 'back to back' is the more easily obtained 'substitution measurement', but it can only provide reliable information if the tyre and flange profile are to the same standard when comparing wheelsets. Since you have current RTR OO product what will best suit is a check gauge of 15mm: the back to back on RP25 conforming tyre profiles will be 14.5mm, but potentially 'something else' on non-conforming profiles, which you can determine pragmatically by test on your layout. (I find that keeping notes is helpful for future guidance...)

Surely not the same 21 pin lokpilot v1 that Bachmann badged as 36-554, long time past? The problem with the motor control was that it was optimised for a large motor with a heavy flywheel or two, and thus it worked very well in centre motor twin bogie diesels, I have quite a number deployed thus to this day, good value for the £8 - £12 asking price when all other good decoders started from £25. However, applied to steam models with smaller motors and limited or no flywheel mass there just wasn't the necessary control refinement. With CV2 turned down to zero, CV's 3 and 4 at maximum, you could tinker all the day long with the sampling and feedback settings without ever eliminating a lack of smooth starting and 'granularity free' low speed running. Back then it was necessary to spend much more (Lenz Silver 21pin) for the desired refinement from 'plug and play', or alternatively to hardwire a Lenz Standard for a £10 saving. Then Zimo came to the rescue, their MX638D price competitive with the Lenz standard eliminated the need to modify - until that went unavailable... A friend bought one of these to go in his ROD, purchased because it was the 21pin decoder the retailer had in the shop. He brought the ensemble to me to see if I could optimise its performance. It just about achieved 'rough and ready'... But that's a comparison on the McD vs BK level; when what we want is ribeye steak minimum.

At least now RTR OO is available benefitting from many of the advances long time established in HO. And the RTR choice is simple enough, OO for good looking but with underscale gauge, HO for correct gauge but ugly distortion of steam traction, both compromises necessitated by the narrowness of UK protoype. There's a reason for P4 and P87 for any that want better... That's the inherent design flaw of the subject, trying to get a boy to do a man's work. The land of wide fireboxes is the one you should look at.😎