jamespetts

That is an interesting hypothesis - one way of testing it would be to compare the build-up of deposits on fiddle yard track which has been nailed down and is not ballasted to build-ups of deposits on scenic section track that has been glued in place with PVA and which has been ballasted using PVA.

This is a bizarre and frankly disturbing response. It is totally inappropriate and verging on the wilfully abusive. (This is not being reported to the moderators because the moderators on this site are also abusers who deliberately enable abuse of this sort by locking threads when there are abusive posts in them irrespective of who is responsible for them, taking no specific action against those responsible for the abuse themselves, thereby allowing people deliberately to stifle discussion of an issue by abusive behaviour). The post to which Robin linked specifically referred to a sample of the black deposits on track having been sent to a laboratory and spectrographically analysed, being found to constitute mostly nickel (III) oxide. Unless one were to think that what is stated in that post was a deliberate lie, for which there is no remotely plausible motivation, that describes a cogent and specific reason to believe that which is stated, viz. that the deposits on model railway track are principally composed of nickel (III) oxide. That is a long way from a bare assertion of the mechanism without any attempt to explain the reasoning. I have not doubted the truth of any descriptions of actual experiments carried out by anyone on this thread. If somebody here had claimed to have sent the results to a laboratory and described the result of a spectrographic analysis on this thread, I should not have suggested that the person was lying. You need urgently to change your attitude to critical thinking and questioning in a radically fundamental way.

I had not - but this is very interesting indeed! Thank you for that. (In summary: laboratory testing shows that the black accumulations are indeed nickel (III) oxide, a black, non-conductive substance which accumulates on track in patterns suggesting causation by micro-arcing.)

I am aware of the learning on polar vs. non-polar chemicals in this context, but the questions that I was asking were not about this specific topic, but rather about the specific other claims being made (e.g. that oxidation of nickel silver occurs in ambient conditions and that these oxides can be removed from the railhead by running trains). May I ask the reason that you posted a link relating only to polar vs. non-polar chemicals in response to this? Robin - I should be very interested indeed in any test results for the consequences of the use of graphite on track.

I simply ask because you appeared to have a very confident belief in some very specific claims (e.g. that the black deposits arise from particles blasted off wheels, that oxidation of nickel silver rail occurs over time without the running of trains and that the running of trains can mechanically remove the oxide deposits) and because you referred to a specific video in which a person whom you described as a research chemist had tested relevant claims. One would normally expect a very specific belief to a high level of confidence to arise only where there is strong specific evidence for that particular belief, so it is very much worthwhile, reasonable and to be expected for a person who is not aware of that evidence to want to ask about it to understand the topic in more detail. Incidentally, I did not suggest that you were being hostile so much as that you might incorrectly have believed that I was being hostile by asking the questions. If you or anyone else ever remembers the link to the video featuring the research chemist, incidentally, please do post it here: I should be very interested to see it.

I have already undertaken general research, which is what lead me to my current understanding. If somebody has a reason to believe that a different understanding is correct, then it is entirely reasonable to ask that person what that reason is. Either the person knows the answer to that question or he or she does not. It takes no effort to state which it is, and, if the answer is known, to state that answer. If the person does not know or will not answer the answer to the question of the evidence supporting her/his conclusion, then it is reasonable for another person not to change her/his view on the basis of the assertion of that conclusion unless and until such reason and evidence should become apparent.

I am not aware of any list in a single external source for all of the hardware requirements or considerations of automation. I and others on this thread have attempted to summarise the relevant hardware requirements as best we can. My own research a few years ago was able to piece together what was needed, although building a small automation test layout also helped. As to the DR4088 devices, Iain Morrison correctly summarises the types. One or two things to know about the S88 bus: first of all, this bus is supported by the DR5000 command station, so you can use this instead of the LocoNet bus if all that you want to use it for are occupancy sensors (implying using a DCC accessory bus for control of accessories such as points and signals). Secondly, it is a less capable bus than LocoNet. Thirdly, it can take one of two cabling types: a bespoke ribbon cable or an RJ45 network cable (at least when used with the DR4088s - I believe that the ribbon cable is the normal standard). Fourthly, its simpler nature may make it more prone to noise/unreliability if you have very long cable runs, although I have not found any problems. Fourthly, it is limited to 16 DR4088CS devices per node. Fifthly, the DR4088LN devices have an S88 bus output, so you can connect a DR4088LN to the LocoNet bus and then connect up to 16 daisy chained DR4088CS devices to each DR4088LN. Finally, the DR4088CS devices are cheaper (even taking into account the need to use slightly more expensive RJ45 cables) than DR4088LN devices. So, it can be helpful, if you need to cluster a few DR4088s together, to use a DR4088LN and connect a DR4088CS right next to it with the S88 bus. You do not need to do any of this and can use all DR4088LNs, but you might find that using a combination of LN and CS types will save a little money.

The reason that I ask for the specific video is because you mentioned that it was from a research chemist, which suggests that there might be a scientific basis for it, which would be very interesting indeed. That something is said in good faith does not make it true; many people genuinely believe things that turn out not to be correct. What I am interested in is thus what the evidence is for the particular mechanisms to which you refer. You refer to "bits of the wheel" being "blasted off" during micro-arcing - do you mean that these are simply fragments of nickel silver chemically unaltered, or are these indeed oxides? Or do you not know? What we do know is that the substance is black - if we file nickel silver, the filings that we get are shiny and grey in colour, suggesting that the deposits are chemically different from the metals from which they are formed (note that wheels on model trains are also made of nickel silver). Also - is there a particular reason that you think that the deposits come from the wheels alone rather than both from rail and wheel in circumstances where they are chemically identical and in contact or close proximity with one another during the micro-arcing events that give rise to the depositions? Or did you mean to state that they come from both? Also, you had mentioned in an earlier post the issue of ambient oxidation - I should be very interested in any research sources that you have on this (or, if you cannot remember specific links, keywords by which you found those research sources and some idea as to how I will know when I have found the specific research sources that you remember having found), as this is a potentially significant mechanism that might alter how best to deal with regular maintenance. I have heard it said elsewhere - without citation of evidence - that running trains can reduce ambient oxidation build up on rails, but, without anybody having tested this, I remain sceptical. It does not follow from the fact that running real trains on real rails prevents the tops of those rails from becoming rusty that the same will apply to oxidation of nickel silver on model railways. The mechanism on real railways is that the trains exert great forces on the rails physically abrading away the rust and effectively polishing the rail heads. I am doubtful that model trains are heavy enough to exert sufficient force to have any significant level of abrasion on the rail head surface. Certainly, one cannot safely assume, without testing, that the same mechanism will work at 1:76th or 1:148th the scale of a real railway, especially since the weight will (approximately) reduce by the cube root of the scale factor and that the wheels and rails are made of different types of metal than on real railways. It is possible that there is nonetheless something similar occurring - but it would be irrational to assume this without testing it. If anybody has actually tested this rigorously, this would be very interesting indeed. Incidentally, I think that you may be mistaking my inquiries for hostility whereas they are actually grounded in a desire to understand whether or not there is sufficient empirical evidence to alter my existing understanding of the subject based on a combination of my own experiments and such information as I can piece together from general knowledge and such research as I have been able to carry out. Obviously, real scientific research on this topic will be superior to that, which is why I am particularly interested in the video to which you refer. Can you not give any clue at all as to what it was called or how I would know if I had found it from a search result? Likewise, if you have conducted experiments or have undertaken research which contradicts the understanding that I have so far arrived at by the process described, then the results of those experiments and the substance of that research might be a good reason for me to update my understanding of the mechanism involved. This is why I ask for details: I am very keen to ensure that my understanding of the subject be as correct and complete as possible. If you are not able to provide those details, then I will have to conclude that I do not have sufficient reason to revise my current understanding. This is not intended as a personal criticism of you; but you should also likewise not be hostile if I continue to state publicly my current understanding despite you believing something different to be true in circumstances where the evidence to which you refer is incomplete or inconclusive.

I have started a new topic as suggested here.

Discussion continued from this thread. Perhaps I misunderstood your post - my apologies. What did you intend to say that the black deposits were made of if not oxides of nickel and copper? Or did you mean that deposits are indeed oxides of nickel and copper? As to the video - there are a huge number of videos on YouTube, and many of those about model railway track cleaning, and it will be extremely hard to find the one that you are referring to without some clue as to how I can identify it. A video by a research chemist sounds much more useful than a general track cleaning video, but I will need some clue as to how to locate it. As to rails going rusty, i.e., ambient oxidation, real rails go rusty because real rails are made of steel and steel rusts at room temperature in the presence of water, which is commonly encountered outdoors. I am not sure whether or not any sort of ambient oxidation occurs with nickel silver; any reliable sources on this would be very interesting (and this would suggest even more of a need for regular cleaning/stay alives than dynamic oxidation only). I am still not sure why you say that micro-arcing does not result in oxidation, however - can you elaborate?

Indeed - real railway grade point position feedback requires monitoring the tiebar, and that is the ideal way of doing it, but that is usually not practical in a small scale. I use feedbacks on the mount itself, which will detect most problems, such as a failed or disconnected servo, mechanical stickage at the mount or an electronic error causing the command not to be sent in the first place. It will not detect a disconnexion between the motor/mount and the tiebar, a failure of the tiebar or disconnexion between point blades and tiebar. I note from iTrain 5's manunal that it does not have point position control built in in the way that TrainController does, so this may be less useful, although this can be customised, I think, from Actions (although I have not investigated this fully - Actions in iTrain are much less powerful than macros in TrainController as iTrain has no user modifiable variables). As to oxidation, it would be interesting to see the video to which you refer. (Rust is a form of oxidation, but not all oxidisation is rust: rust is specifically oxidisation of iron, and model rail track and wheels do not normally contain iron, but rather copper and nickel). What are the keywords with which one can find it? I am not entirely sure that I follow what you mean when you write of the black deposits being pitting - how can a deposit be a pit? Do you mean that this is the material that was once in the pit? It is not shiny and metallic, but black, so presumably the stuff that was in what is now the pit has been oxidised, so these are indeed oxide deposits. I believe that you are correct about using non-ionised cleaning fluids or else risking greater oxide deposits. I do not use alcohol or water for this reason (and yet still get the black deposits as discussed above). Somebody I know has recommended WD40 contact cleaner (not WD40 penetrating oil - the names are very confusing) for this, but I have not tested this myself. I tend to clean the rails dry so far, but might well try WD40 contact cleaner if necessary.

It is slightly more complex than that. TrainController Gold allows for two systems of point position feedback: (1) electronic only; and (2) physical. The electronic only system works by checking to ensure that the correct command has actually been sent out on the relevant data bus, but does not check whether the unit has responded to it. The physical system, which I use on my layout, uses sensors (in my case, micro-switches) to detect whether the point mechanism has actually moved. The former system is of course less effective than the latter, but will at least check that the correct command has got to the relevant data bus. The latter system requires considerably more work to implement, but is more effective and simulates real life modern signalling, in which point position feedback is definitely a thing, more accurately. As to micro-arcing - can I ask how you reach the conclusion that this does not cause oxidation and that running trains does not cause oxidation? It is difficult to find much documented empirical research on this topic: if you are aware of any, I should be interested to read it. My own experiments strongly suggests that running trains does cause oxidation: running a train up and down a clean piece of track for circa 2 minutes will result in black deposits on a previously clean white microfibre cloth that were not there at the beginning of the experiment and are not on adjoining rails that have not had a train run on them. Places where more significant arcing occurs, such as at a spot where a derailment and short circuit has recently happened, causes very large black deposits to build up to the extent that these are visible on the rail head.

A stay alive will not rescue a locomotive that has already stalled: it prevents the locomotives from stalling in the first place. As to wiring, a fault caused by bad wiring will generally render such a large section of track dead that a stay alive will not assist - fixing and preventing these faults is generally much easier to achieve than not only perfectly clean track and wheels but also perfectly flat track.

I am not sure that I follow what you mean by "does not affect the automation" here - if the train not being under automatic control as a result of being stalled is not something that you considers affects the automation, how are you using the word "affect"? If there is a risk of needing to push a train to start it from a stop, then this is a sufficient reason to use stay-alives, since having to do this totally breaks automation by the very fact that starting trains cannot be reliably automatic. Incidentally, most stalls will take place when starting or stopping a train, as this is when the train is running at low speed and is thus most prone to stalling. My own experiments show that N gauge locomotives, even ones with very good pickups such as the Dapol class 50 (Co-Co, all wheel bearing pickup) will stall regularly, even when new, on recently cleaned straight plain track if run at a sufficiently slow speed. Fitting a stay alive completely cures this. Likewise, in 00 gauge, even a tender locomotive with decent weight and multiple pickups (e.g. a Hornby King Arthur) will stall fairly regularly on straight plain track if run at a sufficiently slow speed. Turnouts will tend to increase stalling. If you have a setup in which you are able to get trains to run very slowly over turnouts reliably for a whole exhibition without any stalling at all then that is interesting - but I am not sure how you quantify speed here (1km/h actual or scale?), nor what sort of track that you are using and what you have to to do get it to the state that you describe as "good", and what that state is in physical terms. Incidentally, wiring should not make a difference to this unless it be done very badly.

I do not think that this is entirely correct; first of all, a stall will, of course, affect the automation, as the train cannot be controlled by the computer once stalled, so needs human intervention to move it again, so it is no longer automated. Furthermore, a stall will mean that the computer will lose track of where the train is until it reaches the next occupancy sensor, so can be a major problem if it stalls during a coupling or uncoupling operation. As to stay-alives, their importance may vary depending on the scale; certainly, in N gauge, they are indispensable, especially if you want trains to be able to run at very low speeds (e.g. to accelerate slowly from a stand or when shunting). 00/H0/EM/P4 is likely to require stay-alives for anything other than improbably perfect track cleaned very frequently. 0 is another matter - I do not have experience with this scale, so cannot comment with certainty, but it may still be a worthwhile thing to have if there are locomotives with few axles (e.g. an 0-6-0 steam engine with no tender). Rails and wheels will accumulate not just dirt but oxidation very quickly - the act of running trains will cause oxidation, as, since current is collected from round wheels, only a truly tiny part of metal is in contact with the track at any one time, which can cause micro-arcing, inducing oxidation. This is why real railways do not collect current from the running rails with wheels, but use flat shoegear. The Volk's Electric Railway in Brighton originally collected current from the running rails through the wheels but before long converted to third rail operation. It is thus not practical in many, and possibly most, mechanically to keep the wheels and track sufficiently clean at all times totally to prevent all stalling without stay-alives, at least if not using stainless steel track (and possibly also wheels) or long trains with inter-connected pickups. One very useful feature of Zimo decoders, incidentally, is the function that all of them have when connected to a stay alive to stop the train in a place where track power is available. Without this, even with a very high capacity stay alive, if the train were to stop as commanded at a point which happens to have an accumulation of dirt and/or oxides sufficient to insulate all of the wheels on one side from the track, the train would not be able to start again without human intervention. With the Zimo system, the train would automatically keep moving a few millimetres until it found a piece of track where current is available, and stop at that point to ensure that it is able to move off again under computer command when required to do so.