Wagon Suspension

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Captain Kernow
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Re: Wagon Suspension

Postby Captain Kernow » Sat Jan 23, 2010 8:59 pm

grovenor-2685 wrote:It really is not necessary to quote the Chairman's entire message to add a hear hear or another couple of lines

:oops: :oops: Sorry Keith! Post duely edited!
Tim M
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rjh
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Re: Wagon Suspension

Postby rjh » Sat Jan 23, 2010 9:21 pm

martin goodall wrote:In answer to ‘Flymo’, I confirm that all of my wheels are replacement EM wheelsets, in practice from Kean-Maygib (the steel ones – excellent) or from Alan Gibson (8-spoke and split-spoke).

Flange depth (0.25mm deeper) is not the only difference; the flange width at the flange root is also wider (by 0.1mm i.e. 0.5mm for EM compared with 0.4mm for P4), which is well within the flangeway clearance of track built to P4 standards. (I will return to that point below – there is a reason for that.)

These are ‘fine-scale’ flanges. I understand that the ‘finescale’ 00 wheels supplied by Alan Gibson are exactly the same – the only difference is the back-to-back setting. There is certainly no question of getting coarser-scale flanges to go through P4 crossings. In the early days, EM gauge was just 00 gauge with the rails and wheels pulled out to the wider gauge, but those days are long gone.

Martin,

Is it possible that you can supply me with a pointer to published dimensioned drawing(s) of the aforementioned EM/00F wheel profiles used by Messrs. Kean-Maygib and Gibson, please?

Regards, Rodney Hills

rjh
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Re: Wagon Suspension

Postby rjh » Sat Jan 23, 2010 11:09 pm

martin goodall wrote:Flange depth (0.25mm deeper) is not the only difference; the flange width at the flange root is also wider (by 0.1mm i.e. 0.5mm for EM compared with 0.4mm for P4), which is well within the flangeway clearance of track built to P4 standards.

Hello again Martin,

Furher thoughts...

The (EM, 0.5mm max) flange passing comfortably through the (P4, 0.65mm min) crossing flangeway is not the only critical relationship to be considered, surely ?

The P4 standards documentation (an HTML copy of which is at: http://www.clag.org.uk/p4standards.html ) discusses six important conditions that need to be met (including for the prototype) ,under the heading: "Technical derivation of P4 track and wheel standards".
The same conditions (with ack to P4) are enumerated in the NMRA's "Tech Notes - Proto:Scale and FINE Scale" as "Rules validating the Proto:Scale Track and Wheel relationships.", see: http://www.nmra.org/standards/sandrp/pdf/TN_1_1_2.pdf

P4 No. 2 states:
"CGmin ≥ BBmax + EFmax
The minimum check gauge must not be less than the maximum wheel back-to-back plus one maximum effective flange: this condition represents the checking function, "
All-P4 numbers:
18.15 is equal to 17.75 plus 0.40
P4 but with your EM flange:
18.15 IS LESS THAN 17.75 plus 0.50
It would appear here that the checking function cannot be guaranteed and the flange may sometimes strike the nose of a crossing.

Regards, Rodney Hills

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Re: Wagon Suspension

Postby Bilton Junction » Sun Jan 24, 2010 1:42 am

I don't know, but the idea sounds tempting. Not strictly a question about wagons, so perhaps not an appropriate question in this section. Four wheeled wagons and coach bogies don't seem to be the problem. Is it possible to use EM driving wheels on a pacific and get them through S4 track? I ask because I wonder if it is possible to pack out Romfords EM axles to S4 back to back? Heresy I admit, but it would be nice to have axles with square ends to provide easy and permanent quartering even if it is necessary to turn the flanges down a bit to keep everything Kosher. The possibility of square ended self-quartering S4 axles was dangled before us a while ago by Alan Gibson Workshop but I have not seen any news of further development.
Carl

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Re: Wagon Suspension

Postby Flymo748 » Sun Jan 24, 2010 8:52 am

Bilton Junction wrote: The possibility of square ended self-quartering S4 axles was dangled before us a while ago by Alan Gibson Workshop but I have not seen any news of further development.
Carl


Hi Carl,

I was going to mention that the self-quartering AG wheels had a mention in a recent MRJ, but checking the status on the Alan Gibson website, there is actually a further update from the horse's mouth (no offence intended!):

" 28th Dec 09
Self Quartering Wheels - We are serious about developing the range to include self quartering versions, unfortunately (or fortunately depending on how you look at it) we've been busy supplying to our existing customers. We're hoping that we'll be able to kick start things again in the new year.

25th Jun 09
In a further development, prototype self-quartering wheels have been produced. The wheel selected is suitable for an LNER P2 and was linked into a chassis building feature in MRJ 191 for testing purposes. The theory and process has proved sound. It involves using the existing detail tool; therefore the range can be expanded without producing all new tooling.
The system involves an axle with square ends and a taped hole, the ABS plastic centre has a matching square directly moulded in to it. The wheel is secured to the axle using a countersunk torx screw.
The existing range of wheels will still be available and branded as ‘standard’ with the self quartering version branded as ‘deluxe’. It is intended to initially release popular wheels starting with the standard GWR 4’7” wheel. Work is in progress and releases will be publicised as they are made, pricing has yet to be determined, but will be at a small premium. "

So they are aware that people are waiting. The team at AG must be extremely busy (well, I know they are as I spoke with Colin a while ago) as it was only a couple of weeks ago that I was told that the next batch of kits (GER Intermediate E4) is nearly ready for dispatch.

So I'm sure that having got this far, we *will* see something.

Flymo
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Captain Kernow
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Re: Wagon Suspension

Postby Captain Kernow » Sun Jan 24, 2010 11:49 am

rjh wrote: published dimensioned drawing(s) of the aforementioned EM/00F wheel profiles used by Messrs. Kean-Maygib and Gibson

Am I right in thinking that if you were to take a bog standard set of P4 12mm wagon wheels from Gibson and Exactoscale, then the Gibson ones actually have slightly wider treads, whereas the Exactoscale ones are 'bang on?'

When we were using the (now defunct) Test Track 1 in D.R.A.G., we normally found that wagons fitted with Exactoscale wheels dropped off on our gauge-widened curves (SMP 19.33mm - we'll not repeat that mistake again! ;) ), whereas wagons fitted with Gibson (or Ultrascale) wheelsets normally stayed on. We attributed this to tread width issues, which appeared to be backed up by visual observation.
Tim M
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grovenor-2685
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Re: Wagon Suspension

Postby grovenor-2685 » Sun Jan 24, 2010 1:22 pm

Bilton Junction wrote:I don't know, but the idea sounds tempting. Not strictly a question about wagons, so perhaps not an appropriate question in this section.

Ah well this has got so far off topic already its to late now, should have moved to "Wheel standards" with Martin's first post. :)

Four wheeled wagons and coach bogies don't seem to be the problem.

What problem? Its all that has been discussed so far.
Is it possible to use EM driving wheels on a pacific and get them through S4 track? I ask because I wonder if it is possible to pack out Romfords EM axles to S4 back to back?
Carl


Well, there's EM wheels and EM wheels :( . Markits/Romfords have tyres 2.54 mm wide to RP25 profile according to their website. The flanges will be much thicker than the Ultrascale. Kean Maygib EM wheels discussed above. Then if you are talking Pacifics you have to fit the connecting rods in somewhere.
There are good reasons why wide wheels need a narrow gauge, unless you want overwide cylinders, splashers etc. you have to work from the outside in when setting your dimensions, so a wider wheel needs a smaller Back to Back to keep the outside faces of the wheels in the right place. Look at the 00 wheels of 50 years ago to see why 16.5 was used (or to be more accurate why the scale was increased to 4mm.
Regards
Keith

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Re: Wagon Suspension

Postby Bilton Junction » Mon Jan 25, 2010 3:34 am

I take your point Keith but it has been an interesting debate nonetheless! In truth I have only re-wheeled a guards van so far, to test the crossings, so perhaps I should not comment on goods stock at all! The Bachmann coach conversions were a bit of a pig until I discovered that some of the wheelsets were duff and just needed throwing away. I next adopted Mr Hammond's ingenious simple springing ruse on the bogies, the coaches wouldn't roll down Shap in a strong wind, but they really hug the track and all of its little imperfections. I was seriously interested in proper coach springing but I wont bore anyone about the "bears of Bedford" again.

My problem has been with steam locomotive wheels. Actually, not just steam engines, as the first set of deltic conversions from a well known source were eccentric, wobbly and useless and I replaced them with Ultrascale, eventually, but well worth waiting for. I discarded the other "S4" wheels in the 00 bin. I also converted a K3 that ran well in reverse, allowing the pony truck wheels to follow, but never lead, in an interesting elliptical movement that made me think that I should have made an astronomical model instead.

Flushed with these successes, I then bought an S4 conversion set for an A3, from a well known source, the drivers had spokes like a Welsh slate wagon; they were too horrible to look at, let alone fit to the engine. They went in the 00 bin as well. I used the bogie wheels but they had a curious little up and down motion at low speed and expecting this eccentric rubbish to work was asking too much, it didn't. I probably should have just bought some alternatives from Ultrascale but I was too mean and also distrustful of my skills by that stage. So I put the Hornby drivers in the lathe and modified a form tool that my Dad had made for some long forgotten purpose many years ago. My workshop skills have become very rusty with too many years wasted in DIY alternative hobbies (or were probably always fairly crap) it still made me suspect that I could get a more concentric result by putting a good quality RTR driving wheel in the lathe; the bogie wheels were another matter. Unless I have made a big booboo with the Verniers, I probably had; there is enough metal in Hornby A3 drivers to produce a wheel to acceptable (?) S4 dimensions. The wheels seemed alright but I spoiled them when I reamed out the lovely centre that originally located firmly on a wonderful splined, permanently quartered, axle. I know people say there is nothing to quartering but however easy it is set up, keeping it right seems to be another matter.

I saw the article in MRJ about Alan Gibson square axles but nothing has emerged so far. I also saw a rather nice A4 conversion to EM in MRJ using Romfords. If unmodified Romfords driving wheels would cut a furrow through my meticulously laid track to lovingly produced S4 standards, or as close as I can get to them, I would be a happy man/philistine. I may even splash out on some decent S4 bogie wheels to fool everyone that I have got it all right! If not, then turning down the back of Romfords RP25, which would be much easier when simply facing the back of the wheel in order to reduce the flange and simultaneously increase the back to back might be an option? (admittedly the profile might vary from strict S4 but still bring it within a workable range and acceptable appearance) I just wonder if anyone has tried that before I write-off another set of wheels?
Carl

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Re: Wagon Suspension

Postby martin goodall » Mon Jan 25, 2010 9:49 am

DaveyTee wrote:A little off topic ("Wagon" suspension), but I assume that while rolling stock with EM profile wheels runs on P4 track, the same cannot be said of locos?

David


I've had my fun in this debate (for now at least), so it's probably time to get back to some model-making, just as Mr Chairman suggests. Particularly, as we have all wandered somewhat off-topic.

But in answer to Davey, there is no reason why it shouldn't work for locos too.

Mike Sharman always used to say that his EM loco wheels would run through P4 points, although most P4 modellers preferred to order the P4 wheel profile from him.

I have started a conversion of a Hornby 14XX, and the wheels I am proposing to use are 'EMF' wheels from Ultrascale. It is a little known fact that Ultrascale produce a loco wheel profile which they term 'EMF'. It is EM profile, but only 2mm wide (as compared with the normal 2.25mm width of a normal EM loco wheel). They can be ordered with P4 axles. You just need to specify what you want. I have bought a number of other EMF wheels from Ultrascale for future loco projects.

However, the regular Ultrascale conversion packs are only available either with orthodox P4 or EM wheels, so the locos I have converted with those conversion sets are P4 and likely to remain so (at least for the foreseeable future).

I will report results on the 14XX in due course (under the right topic heading next time!).

Meanwhile, its back to the workbench.

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Re: Wagon Suspension

Postby martin goodall » Mon Jan 25, 2010 10:48 am

Sorry, chaps. When I wrote what I thought was my last contribution on this topic for the time being, I had not realised there was a whole extra page of queries.

The following is just to answer the factual questions. (I’ll leave the philosophy to others.)

Rodney Hills : Is it possible that you can supply me with a pointer to published dimensioned drawing(s) of the aforementioned EM/00F wheel profiles used by Messrs. Kean-Maygib and Gibson, please?

Regrettably, I don’t have these to hand right now. I vaguely recall that they were quoted by Iain Rice in one of his books, but I am not sure whether these standards are actually reproduced in the EM Manual or not. The last time I looked I seem to recall that they still had the ‘old’ standards there, but I am open to correction on this.

Rodney Hills : [Re check clearances etc. – see the sources quoted]

I am aware of the theory. All I can say is that I haven’t found any problems in practice. It may have something to do with the way I build my points (as I have always been in the habit of ‘reversing’ the flangeway and check rail clearances, because even with P4 wheels, there is at least in theory a possibility of the wheel flange hitting the nose of the crossing vee – due to the over-generous clearances allowed in the P4 track standards. There are a couple of C10 turnouts laid on a curve on the Burford Branch and it seemed to be asking for trouble if I had stuck to the laid down check rail standards.) But I am not sure if this really makes a practical difference to the successful running of EM-profile wheels on my layout.

Reducing the running clearance (either by using EM-profile wheels, or by widening the back-to-back of P4 wheels to the “Scale Four” dimension) might solve this problem in any event, as it is the propensity of P4 wheels to ‘hunt’ on the track which is the real source of the trouble.

Bilton Junction “Is it possible to use EM driving wheels on a pacific and get them through S4 track? I ask because I wonder if it is possible to pack out Romfords EM axles to S4 back to back?”

You definitely won’t get Romford or Markit wheels to work on P4 track. They have the wrong flange profile and the tyres are too wide to be accommodated inside splashers etc. if opened up to P4 back-to-back. They are very good quality wheels – but only for 00 and EM use.

Captain Kernow : “When we were using the (now defunct) Test Track 1 in D.R.A.G., we normally found that wagons fitted with Exactoscale wheels dropped off on our gauge-widened curves (SMP 19.33mm - we'll not repeat that mistake again!), whereas wagons fitted with Gibson (or Ultrascale) wheelsets normally stayed on. We attributed this to tread width issues, which appeared to be backed up by visual observation.”

Exactoscale wheels do have a dead-scale tyre width, and quite frankly it is too narrow for practical model railway use – hence the problems encountered by DRAG (and also by others who have tried using them). The 2mm tyre width normally specified for P4 carriage and wagon wheels is over-scale, but is a sensible compromise.

Keith Norgrove : “There's EM wheels and EM wheels. Markits/Romfords have tyres 2.54 mm wide to RP25 profile according to their website. The flanges will be much thicker than the Ultrascale and Kean Maygib EM wheels discussed above.”

Exactly so. As previously noted, you can only use ‘modern’ EM-profile wheels. Markits/Romfords (including the coach and wagon wheels) won’t run on P4 track. I did actually try out some of their wagon wheels to make sure – I try to work on the basis of practice rather than theory.

“Then if you are talking Pacifics, you have to fit the connecting rods in somewhere. There are good reasons why wide wheels need a narrow gauge, unless you want over-wide cylinders, splashers etc. you have to work from the outside in when setting your dimensions, so a wider wheel needs a smaller Back to Back to keep the outside faces of the wheels in the right place.”

Yes, that’s right. The practical answer to this problem is Ultrascale’s ‘EMF’ wheel profile, referred to in my last post. Then your wheels will be no wider than P4. But if you can spare an extra 0.5mm between the insides of the splashers etc., then 2.25mm wide EM profile wheels might still be OK.

Incidentally, the trick for getting any 6-coupled loco round the curves on a P4 layout is plenty of side-play in the middle axle, but of course you need the room for that inside the splashers/tanks/footplate, etc.

Bilton Junction : “I next adopted Mr Hammond's ingenious simple springing ruse on the bogies; the coaches wouldn't roll down Shap in a strong wind, but they really hug the track and all of its little imperfections.”

I have never tried out Ray’s idea, but I was impressed when I first saw it, and it has the advantage of being a fairly quick and simple job to fit. It was written up in MRJ some time ago – sorry I don’t have the reference to hand.

Now I really must get back to work!

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Re: Wagon Suspension

Postby Julian Roberts » Mon Jan 25, 2010 3:11 pm

Seemingly it's not only me that has learnt quite a lot from this discussion topic, so I'm glad to have opened an interesting discussion.

In the MRJ 130 I referred to as answering my original query there are two pictures of the Bachmann wagon, "before and after". One with original Bachmann wheels, one with the P4 replacements. It would be interesting to have three pics - these two, and one with EM replacement wheels.

For me it is steam locos with their large wheels, and inside frames, that look so much better in P4. But with outside framed, small wheel stock - i.e. nearly everything else except the latest inside framed bogies on the Class 220 Voyagers for example - I think I may not be particularly fussed about the difference of a slightly deeper flange and wider tyre, and if it works on P4 track, great. However, is there not more likely to be a problem the shorter or sharper the points / greater the wheelbase, as the flange angle of attack increases therefore using up more of the gap between stock and wing rails? I doubt if this is an issue on our West of Scotland 4mm Group layout 'Calderside', which is the layout I am modelling for, with its generously dimensioned pointwork, but points in the fiddle yard are tighter.

Well, I'll suck it and see. WIth my still future set of wagons, I'll probably try both drop in EMs and compensated P4s, seven wagons each perhaps. In the distant future I'll report back on the outcome.

Was not EMf (mentioned many posts back) an abbreviation of 'EM fine' - EM track with narrower flangeways and clearances, and is that not used at Pendon? I have wondered why the flangeways are so wide in the normal EM standards.

Perhaps there is case, for some of us, for a "course" P4 wheel, 2mm wide but with EM flange depth, for the common wagon and coach sizes? However, perhaps I should look at that discussion topic elsewhere on the 4um.

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Brian Harrap
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Re: Wagon Suspension

Postby Brian Harrap » Tue Jan 26, 2010 12:09 pm

Heck, it's taken me nearly as long to read about what wheels and things I should have been useing all these years than it actually took me to build the layout. Regards Brian.

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grovenor-2685
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Re: Wagon Suspension

Postby grovenor-2685 » Tue Jan 26, 2010 10:30 pm

Exactoscale wheels do have a dead-scale tyre width, and quite frankly it is too narrow for practical model railway use – hence the problems encountered by DRAG (and also by others who have tried using them). The 2mm tyre width normally specified for P4 carriage and wagon wheels is over-scale, but is a sensible compromise.


Well now, adopting your preference for practice over theory I have quite a number of wagons fitted with these wheels running round my layout without any noticeable problems. I would suggest that if you have problems, as was mentioned in the DRAG example, your track is outside the specified tolerances.
Keith

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Re: Wagon Suspension

Postby Bilton Junction » Wed Jan 27, 2010 1:48 am

Surely it is always a matter of practice over theory? Were not the original society standards a matter of discussion/argument/litigation/compromise? I watched a lovely EM model at an exhibition recently, it looked wonderful. I told my eldest son that I wish that I had adopted those standards and that it would have been far easier and faster to get the job finished. There were no trains running. Then I watched the exhibitor pushing a bogie up and down the same bit of track. The narrow meeting of regulation, hope and compromise. Clearly no panacea. Build a bit of S4 track to 0.05mm accuracy then drop it into a pool of PVA or bang it down onto a bed of solvent adhesive that smarts your eyes and dissolves your slippers and the carefully achieved standards won't ever be the same again. Push Mr Sanders (inestimably useful) Rogering gauge through it and the chairs spread and the rail twists, bingo all is perfect! We can't scale the creation to 1:76.2010. I don't regret having started but surely everyone makes compromises. I always find this website helpful. The debates in this thread have been particularly helpful,even if some have perceived heresy and revolution.

You are not the same people who left that station or who will arrive at that terminus whilst the narrowing line of rails slide together behind you. Obviously T S Elliot also had problems with gauge!

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Captain Kernow
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Re: Wagon Suspension

Postby Captain Kernow » Wed Jan 27, 2010 3:33 pm

Brian Harrap wrote:Heck, it's taken me nearly as long to read about what wheels and things I should have been useing all these years than it actually took me to build the layout. Regards Brian.

Ah, living proof! ;)
Tim M
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jim s-w
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Re: Wagon Suspension

Postby jim s-w » Thu Jan 28, 2010 12:03 pm

Hi All

I still cant help thinking after all of this discussion that the EM wheel thing is a solution to a problem we don't have. All this talk of "it will work fine if you get your track laying bang on" is a bit of a red herring as after all, if your track is spot on then P4 rigid will work without any problems. Its actually pretty surprising just how bad P4 track has to be for simply re-wheeled RTR to not work! Our test track is truly shocking but RTR stuff runs round it all night!

Cheers

Jim

martin goodall
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Re: Wagon Suspension

Postby martin goodall » Thu Jan 28, 2010 2:21 pm

jim s-w wrote:Hi All

I still cant help thinking after all of this discussion that the EM wheel thing is a solution to a problem we don't have. All this talk of "it will work fine if you get your track laying bang on" is a bit of a red herring as after all, if your track is spot on then P4 rigid will work without any problems. Its actually pretty surprising just how bad P4 track has to be for simply re-wheeled RTR to not work! Our test track is truly shocking but RTR stuff runs round it all night!

Cheers

Jim



Hauling RTR stock with P4 wheels (with no springing or compensation) round a main line may be fine, but propelling the stock through pointwork may be slightly more problematic. I did find there was a problem with P4 wheels (admittedly only occasional, but enough to be irritating), and that's what set me off on an examination of the wheel standards. It was the slightly deeper flanges in EM (10-thou deeper if I remember rightly, or 0.25mm) which were the attraction. It was quite by chance that I discovered when looking at the published standards that an EM-profile wheel flange should be able to negotiate P4 track. So I tried it out with a handful of wagons and coaches, and it worked. Since then I have converted quite a few other vehicles wtih EM-profile wheels.

Of course, if I had found that EM-profile wheels wouldn't go through P4 points and crossings, that would have been the end of the experiment. Out of curiosity, I also tried out some RP25 wheels (which, as I had expected, won't work on P4 track), and some Markits wagon wheels (2.54mm wide, which is too wide to fit inside wagon underframes and bogie sideframes when opened up to the P4 BB dimension).

If I had not gone over to using EM-profile wheels, I think I would probably have adopted Ray Hammond's bogie springing system for coaches and MJT inside bearing rocker units for 4-wheel wagons. I don't think I would have just stuck P4 wheels in the RTR stock without any way of allowing the wheels to adapt to minor variations in rail level.

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jim s-w
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Re: Wagon Suspension

Postby jim s-w » Thu Jan 28, 2010 2:27 pm

martin goodall wrote:
Hauling RTR stock with P4 wheels (with no springing or compensation) round a main line may be fine, but propelling the stock through pointwork may be slightly more problematic.


Not in my experience. And as you keep saying its practical experience that matters not theory. Amlwch is an end to end shunting layout and the only wagons that gave problems last show were a ferry van (very long WB but rocking compensation) and a parkside tippler (again with rocking compensation) most of my other wagons are rigid.

My experience shows the MJT inside CCU's are a whole lot worse than rigid in the way the wagons run. I would choose Sprung - rigid - compensation in that order.

In fact i might even go as far to say the derailments you have seen at shows on P4 layouts might even be down to over complication and the poor instalation of devices supposed to fix another problem we don't always have. Perhaps another topic?

Cheers

Jim

Bilton Junction
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Re: Wagon Suspension

Postby Bilton Junction » Fri Jan 29, 2010 12:17 am

Hauling RTR stock with P4 wheels (with no springing or compensation) round a main line may be fine

I don't agree with that, I found a lot of difficulty getting unsprung coaches to follow an unsprung diesel around my track. The track was fairly well laid and checked, then ruthlessly ripped up and relaid or modified where it didn't fit. Alas I did not have Mr Sanders gauge at first. It really should be supplied or at least recommended, to all members joining the S4 society! I found by trial and error that applying Ray Hammond's simple wire spring to the axles cured most of the problem with the coaches. The converted coaches stayed on the track and after much observation of the behavior of the others and noting the cause of all derailments, I found that the unsprung coaches were usually the cause of derailments and converted them. Two 10BA bolts and three inches of phosphor bronze wire is a very cheap but effective conversion. I found that the brake ends next to the loco. were still a problem, so weighted them and increased the strength of the springing, to make them float rather than being at the top of travel. I had already noted that the deltic bogies with high pivot points had a pronounced yaw and were problematical. Applying small pieces of padded tape to the body and bogie; a simple secondary spring I suppose, cured the problem. Then I changed the couplings because interaction between adjacent vehicles seemed to lift one or other off the rails. I found that the simple Glatzl dummy buckeye couplings fastened rigidly to the coach bodies worked best especially with a bit of microgrease. Eventually after much heartache, cursing and grief I can say that even I can get S4 to work; but it has not been easy. A nine coach train will now reverse reliably at half speed and I have sufficient confidence about the test track (most of the main line) that I have started to lay the yards.

Apologies to all who have been down this route decades previously. It isn't easy is it? But not impossible. I was not aware that the EMF profile wheel had very little greater flange depth (I had envisaged Romfords flanges) In practical terms I doubt that 0.25mm greater flange depth on The EMF wheels would have stopped my coaches coming off the track. I haven't tried reversing wagons into the reverse curves of my newly laid south yard yet though if they give trouble I will try simple wire springs on the axles first as it is easy and cheap. I certainly would not discount the idea of EMF wheels and intend to try it on an unsprung pacific. My home-modified turned down Hornby wheels were a bit of a disaster as they climbed out of the track on curves before sideplay operated. Perhaps that was just a problem with the contour of the flange root, but I imagine that the extra flange depth might allow sideplay to work more effectively in an unsprung loco. I am going to build up the A1 Easichas first though, as springs certainly do seem to help!
Carl


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