Simond

Steve Looking back at mine, I think the one thing that would have made mine much better would have been to make a circular plinth to put the rail on. Just to lift it up. When I surfaced the central well, I used some small ballast, maybe fine 4mm scale, but it ended up a little higher than the base of the chairs, and it isn't right. I'm not going to change it, but I'm sure that I could have done better if I had somehow made the chairs a bit higher. Hope it helps - I can do a photo or two back end of next week if it would help Simon

Rod I made a paving slab platform, much smaller than yours, by painting plastic sheet in varying shades of grey, and toning it down with talc. I then cut the sheets up into paving slab sized pieces, and laid them on a wooden block. I used Slaters brick sheets for the sides. I don't have a photo of it, so can't post anything this week, but I think it looks pretty good, as the slabs were laid in a different order to the way they were originally painted, so the colour variation seemed to work. I think you'd need a guillotine for a big platform like yours Hth Simon

Does anyone do a sound project for these - I've been searching with no luck so far? it would be nice, and eminently feasible, especially as there is a 1361 and a 1366 preserved - I guess they sound sufficiently similar to enable a common project for both? best Simon

Street running is an interesting point, happened in Birkenhead docks too, and I'm sure, many other places where locos, people, horses and road vehicles used the same streets. I wonder what the rules were for "covering up" as the various tramways, standard and narrow gauge, needed to do, whereas it was clearly not needed in other locations. Man with a flag? Perhaps the docks were not "public roads" and thus subject to different regulations? best Simon

Chaz. As I said, personal choice is the final arbiter, hopefully supported by good advice and accurate info. In this case the "wrong" is that four-point is not three point compensated, the issue is physics, not prototype fidelity. It's not opinion, it's fact. But of course, it might not matter - the advantage of "right" over "nearly right" might well be negligible, or at least not worth the added effort. In terms of workload, I think springing is quite a bit more hassle to get right, particularly if you build "floating" rather than "sprung one way", and for that reason, I'm inclined to compensation Having in mind Chris' concerns over his experience, I'm sure building it four point compensated per the instructions will give a satisfactory result, and whether I would do something different, sillier or not is really only of academic interest. (And I too have done "silly") Chris I haven't used the jig, but I expect it will be easier than the rubber band, paper clip, hair grip & balancing acts that I resort to! Good luck, looking forward to seeing how you get on Best Simon

Miss P I do agree with your concerns over lateral stability, see my earlier comments regarding 4-4-0 where the CoG may be near to or even ahead of the leading axle, & 4-6-0 locos, where the CoG will tend to get very near the mid point between the two front axles. In both cases, even if it is within the support triangle, here will be a real risk that hitting a corner at speed might easily lead to roll-over. This is clearly one area where springing can have an edge over three-point compensation, and four point "quasi-compensation" would have an advantage - and Chaz, even my very small layout has some horrid twists after a few years - those of us who run in the garden will have undoubtedly experienced some less-than-perfect track too. In these cases, it must be true that, at some places, only one axle is in proper contact with the rail on one side of the loco, and thus, however briefly, pick-up will suffer. If you're unlucky this will coincide with the chassis tightening up as the rocking beam bearing misalignment reaches a maximum, and disappointing running may well result. Worst case might lead to derailment, but this seems improbable with normal 0F flanges. Whilst you, Michael Edge and Chaz all report successful outcomes, a little part of me says, "yes, ok, but it's still wrong", and personally, I would tend to try to modify the kit so I felt it was "more correct", but in the end, I guess it is a case of rule one. Assuming it is free running, it can't be worse than a rigid chassis so my advice to the original question would be , "build it as the kit was designed". Best Simon

I can't really see the point of "4-point" compensation - as Miss P says, it's a fudge, and like a four legged stool, only works on a flat surface, or, in this case, one that has vertical curves, but no twist in it. I have built 3 sprung, 1 hybrid, and 9 compensated locos, and one rigid one, and they all run satisfactorily. Springing is generally more challenging, and I find that I can't see a significant benefit over compensation, although I think both are better than rigid. I think Chaz mentioned in his Dock Green thread how satisfying it is to see the suspension "work" as the wheels run over something like a match. For those who are not familiar with three-point compensation, the aim is to reduce the support of the loco to three points, irrespective of how many wheels the loco has, which means that there will never be any rocking, like a three-legged stool, and the weight will be more-or-less evenly shared between the wheels. The simplest case is a four wheeler. If one axle is rigid and the other can rock about a fulcrum at its mid point, provided the centre of gravity of the vehicle remains within the imaginary triangle defined by the rigid bearings and the fulcrum, the vehicle will be stable, and will maintain wheel contact, and therefore, pick-up from all four wheels. There are two ways of achieving this on a six-wheeler. The simpler route is to place a cross-beam between two of the axles, and pivoting on this, have a longitudinal rocking beam bearing on the tops of the axles (usually leading & driving) The other (usually trailing) axle is rigidly supported in the frames. This allows two axles to rock, and they will also rise and fall to follow vertical curvature of the track. It is usually simplest to have the driven axle rigid, as there is nothing in the way, but of course, this only works if it is the leading or trailing one. The support triangle is now between the two rigid axle bearings, and the centre of the rocking beam If you need to drive the middle axle, for example, an 0-4-2, or because you want working valve gear, the other approach is applicable. In this case, you provide a pair of independent rocking beams acting on the axle boxes of two axles much as the kit does - but the axle boxes must not be attached to the beams, otherwise it will bind as shown in Miss Prism's post above - they need to be able to rock to allow the wheels to follow any twist in the track. The motor & gearbox can fit between the rocking beams. The third axle has to be able to rock from side to side to accommodate twists in the track. In this case the support triangle is between the pivot points of the rocking beams, and the central fulcrum on the third axle. In eight-wheelers, you need three rocking beams. One is used to compensate two axles as in the first solution for 6-wheelers, and the other pair are arranged as in the second solution - thus the support triangle is between the centre of the single rocking beam, and the two pivot points of the pair of beams. At this point, I wish I had a CAD app on my ipad! 10-wheelers add a further challenge - rigid is not good, particularly if when the boiler and chassis are assembled, the chassis twists, as I discovered, and fixed, on a pal's 9F. For full compensation, a rocking beam, supported by a rocking beam is going to be necessary to get from three axles to a single point of compensation, and that will be tricky - like Gresley (actually Webb) conjugated gear, so another approach is probably easier. I've never built a 10-wheeler, or a CSB chassis, but it might be a good option here, alternatively, build a hybrid, light springing on the centre axle and compensate it as an 8-wheeler. If you spring or compensate, you do need jointed rods, otherwise they'll bind, or bend. It is possible to include bogies and pony trucks in the compensation, and certainly helps with awkward cases, a 2P I built springs (sorry) to mind. In this case I put a rocking beam between the bogie pivot and the centre of the leading axle. The rear axle was rigid, and motorised. I did something similar on my Castle, as the centre of gravity was too far forwards to allow me not carry some weight on the bogie. The middle axle is sprung, and the rear is rigid. Best Simon

I'm perplexed by the first diagram of the chassis. Are there two parts #3 as it appears - one close to each frame? And if so, does the rear axle rock as it would need to in order to provide true "three point" compensation? Or is there only one part #3 rocking on the middle of the leading & driving axles, in which case the rear axle can be fixed in the frames? Thx Simon

Jeff I take it from your question that you haven't yet got a solution for your t/t? Mine works (not that there's a layout for it yet) almost perfectly, much as a result of the help I got from your thread - if I can offer any help, just shout Best Simon

Thanks Rod Do (did) your locos have large motors? I'm surprised, and maybe a little concerned, that you've discovered this, as I've built some 12 locos in 7mm, with motors ranging from Portescaps to a Crailcrest (bit too wide for wasp-waisted Churchward fire boxes!), and all of them are on standard decoders, mostly Zimo, with no problems so far. I've only got two with sound, (Howes Loksound v4) and neither of them has been tested with a "wheelspin load" train yet, so perhaps I need to do some experimentation before spending more of the hard-earned! Best Simon

Rod I guess you have to do what you did - ie apply a DC voltage and see which way it goes, unless you are blessed with the ears of a bat! I think therefore that a suitable resistor in series with the speakers to limit the current is all you can do I read on through the thread, which I have very much enjoyed (being a Birkenhead lad, born, bred & buttered!) and saw you did have some problems with your sound decoders - were these eventually resolved? The thread has given me some further inspiration for my project, it looks great, so thanks Simon

Sorry this is a quote from a post from last year, but do be careful about putting 3-4V DC across your speakers - that's about an Amp on a 4 Ohm speaker and they won't survive it for long! Sorry for the double-edit: I mis-read the speaker bit and thought you were likely to fry your chips... Best Simon

Martin Post the code! Another newby will follow your footsteps, and learn from it, and maybe one of the experienced types will say "oh, but if you do... It'll be better/simpler/cheaper/quicker" and we'll all learn! Best Simon

Given that I have the artistic talent of a hippopotamus, it may be invidious to criticise, but for me the sky is too blue in the knife work. Conversely, I think the houses across the river are marvellous, giving a lovely sense of distance. I do hope your M-I-L doesn't mind the commentary, she deserves great credit! Simon

love it - the one thing I try to avoid - soldering to the brass thing that I have just glued to the plastic solebar... I do agree that the cast brackets can be a bit of a job - but is that the execution of the part, or the material? Definitely these would be better if the brackets had holes and the pins were simply brass nails, or something similar. best Simon

Hi Chaz Enjoying the photo-history & looking forward to the locos. Thanks for adding a few details about techniques. I'm surprised by your comment about mixing materials in a kit - I take the view that this offers the manufacturer the opportunity to optimise material for function, which should make for a better finished product - just as long as they are not expecting me to solder to the thing that I just glued to the plastic part... Do echo your sentiments re some Slaters stuff however. I recall building a couple of their 7mm bogie clerestories with a mixture of relief & dread. They look the part, but I'm sure it could have looked as good with a bit less complexity! I might tackle another of their milk tankers one day... Best Simon

Chaz Please do let us in on your painting & weathering techniques - buffers & coupling - powders or drybrush, or ...? And, how would you have glazed the duckets ? (I'm curious, but as my theme is GW, no more than that!) Thx Simon

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Alan Thanks for your thoughts. I shall use a computer PSU at least as an experiment. I'm certainly not going to open it up, so that's not a concern (any more than I'd be worried about having a valve guitar amp or an old-fashioned CRT TV), but the zero volt thing is an interesting point - probably not an issue for point & signal control, or lighting, but probably well worth avoiding for track where multiple feeds are envisaged - and where human contact might be expected to be the norm, eg for track cleaning. Shouldn't be a single point of failure risk, but could make another failure worse, perhaps. Thanks again Simon

Alan This thread http://www.rmweb.co.uk/community/index.php?/topic/9726-using-an-atx-computer-power-supply/ Best Simon

Hi all Thinking of the day when I will need a power supply to run signal & points servos, a desktop ATX power supply seems like a useful option. http://en.wikipedia.org/wiki/Power_supply_unit_(computer) Prices from about £13 for 500W, which should be enough... (Though this is split between 3.3, 5 & 12V, all of which are regulated and over-current protected) Anyone tried it? (A check on the search did lead to a thread from 2010 largely promising death & calamity to anyone who even considered it - I was hoping for a less sensational response) Best Simon

Ozzy I think you might have difficulty turning a loco with 64' wheelbase on a 65' table - I'd need to draw it to check, but I can imagine that the flanges might not quite clear the railhead of the fixed rails - it would certainly be close - in any case, you'd need an unnatural precision in parking the thing. I also suspect that the balance might be a bit important if you're pushing it round by hand, but I've never done it, myself. Best Simon

I built one. I would say that following the instructions you'll get what you bought - if I were to do it again, I'd spend more time planning - mine was a GWR one and I am sure I could have improved the looks and detail if I'd spent more time thinking (and looking at pictures) before diving in - particularly a foundation for the ring rail above the pit bottom. No major criticisms of the kit apart from the tedium of cutting endless riveted brass angles to fit the "panels" on the girder sides - it would have been hugely better if each of these had been an etched "entity" rather than 4 different lengths of etched angle riveted individually. I suspect that this may not add (much) to the etching costs of the kit, and would certainly improve the build-ability, and maybe the appearance of the finished article. Given that there were some blank bits of the etches, it might have been nice to have a few notice boards, or something equally useful, but this is being over-picky perhaps, and the details of the locking gear are a bit sparse. Pre-plan if you want a DCC version (supply rails from spindle and ring-rail with polarity controlled by relay or reverse loop module) or DC (supply from split ring rail) otherwise risk of shorts and no sound. Lots of photos and stuff about stepper motors on JeffP's thread. Best Simon

Eric I have not yet had a chance to try your code. I am interested by your pi-server approach and JMRI but have a) no experience of it, b) no time and c) no need at the moment! My tendency would be to have signalling separate from driving, but there is clearly an option to have an automated fiddle yard - I think there was a Peter Denny article in RM, years ago entitled "An automated Crispin" in which some bells and whistles and some clever woodwork replaced his son in the operation of his FY, so the concept is not new, but certainly interesting. Do, please keep going, and keep the posts coming.

Controversially, lots lower than the high one, but a bit higher than the low one... Sorry! Simon