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11 hours ago, thegreenhowards said:

There is what looks like a standard LNER rectangular monsoon vent ...

 

Andy

Before people start incorrectly referring to these as Monsoon ventilators this is what an LNER Monsoon Ventilator looks like:

Image351.jpg.c7391dc257bea9b29320275ea6d36d87.jpg

 

The vent you are referring to is a Extractor Fan Zinc Cowl. I have (I think) posted a drawing of these previously but havn't a clue where.

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24 minutes ago, thegreenhowards said:

Thanks Andrew,

 

It’s interesting that your picture has a square item instead of the second cylindrical thing. The Isinglass drawing warns that different vehicles had the details in different positions. To misquote our leader ‘the joys of coach picking’!

 

Andy

 

Evening Andy,

 

I think that the 'cylindrical thing' is just an elongated type of torpedo vent, to accommodate a larger pipe. I suspect that the 'square item' is a later addition, a replacement for the same type of second T vent, that seems to be common on other Buffet conversions. The image is quite late on ( maroon drab with orange and black go faster stripes) perhaps it reflects BR's make do and mend philosophie on older stock, rather than an original feature. 

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7 minutes ago, MikeTrice said:

Before people start incorrectly referring to these as Monsoon ventilators this is what an LNER Monsoon Ventilator looks like:

 

The vent you are referring to is a Extractor Fan Zinc Cowl. I have (I think) posted a drawing of these previously but havn't a clue where.

 

'T other type I refer to as 'butterfly fan vents, for obvious reasons, but that is my own nomenclature.

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4 hours ago, grob1234 said:

Just a little tangent from me...

 

There was a discussion a while back about the Comet V2 chassis, and the Cylinder Block covers.

 

I found mine to sit low by a couple of mm, so I checked against the drawing:

IMG_7087.JPG.422019cf63eeb7ece51e60914de4b34c.JPG

 

I discovered that the comet cylinder casting was about 2mm to short:

 

IMG_7088.JPG.e189035cacd04b2e8b944812b0c97d20.JPG

 

I soldered a slug of spare whitemetal on top of the original casting, and now after dressing back, it sits perfectly:

 

IMG_7089.JPG.f6b03e43228f8570bfb838778dbec092.JPG

 

Hopefully, having not altered the gemoetry of the valve gear, it'll all work without any modification, plus I think the modified cylinder block captures the taller look of the prototype:

 

GA_at_SVR.jpg.7c1bef14adad2d7928cdb389933e16d2.jpg

 

https://en.wikipedia.org/wiki/Gresley_conjugated_valve_gear#/media/File:GA_at_SVR.JPG

Looks much better, Tom,

 

Has the vacuum ejector pipe broken on your model?

 

Regards,

 

Tony. 

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47 minutes ago, Headstock said:

 

Evening Andy,

 

I think that the 'cylindrical thing' is just an elongated type of torpedo vent, to accommodate a larger pipe.

I think the 'cylindrical things' are the cowls for the boiler and stove. Probably these:

243227222_IMG_9348-Adjusted.JPG.d11efe915abf49678aaee84af56f26c0.JPG

 

779974552_IMG_9350-Adjusted.JPG.845a4b31b2f66fafe8f261f84092924f.JPG

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30 minutes ago, MikeTrice said:

I think the 'cylindrical things' are the cowls for the boiler and stove. Probably these:

 

 

Evening Mike,

 

I'm sure that's what they are but not so much that shape on some. Some photographs seem to show coned ends rather than curved, similar to torpedo vents. They lack the space between the roof and the curved ends of the cowling as seen in the drawing. That could be a BR feature, as others closely resemble your drawing, as below.

 

cowling.jpg

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15 hours ago, Tony Wright said:

as is well-known, I have no time for friction-fit drivers

 

Not wishing to re-hash previous discussions (but with 2061 pages, left with not much choice), could you please explain why Tony? I've recently started using Gibson drivers, and I think they are far superior to Marktis/Romfords in appearance - not that I think those wheels are particularly bad though.

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7 hours ago, Theakerr said:

The mystery of the electronic media.  On Tuesday I made two posts, one is on the thread the other seems to have disappeared.   So, to the other.  Does anyone have a way of removing the overhead electric warning flashes from a Hornby loco without damaging the finish?

Thanks

Thank Gentlemen for the replies.  I have tried using a toothpick and aircraft perspex polish with essentially no impact.  I have some t-cut and will give it a try.  I think at this point the aim will be not to remove it but to dull it down so that it doesn't jump out.  I don't mind a little weathering and will be OK with it on the front end but not so keen on the body.

I use T-Cut but with a cocktail stick whittled to a chisel end rather than the oft-recommended cotton bud. I find that gives me more control and lets me see what I'm doing more easily.

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6 hours ago, Jack P said:

 

Not wishing to re-hash previous discussions (but with 2061 pages, left with not much choice), could you please explain why Tony? I've recently started using Gibson drivers, and I think they are far superior to Marktis/Romfords in appearance - not that I think those wheels are particularly bad though.

I'm glad to explain my reasons for disliking friction-fit driving wheels, Jack.

 

Granted, my experiences are from several years ago and the prejudices I developed then are far too entrenched now. I'll also state that I've never used Ultrascale's wheels.

 

Why 'prejudices'? Out of the dozen or more times I attempted to use friction-fit drivers, I never found a set in which all the wheels were true-round and concentric. All resulted in the locos above them 'nodding' up and down in motion. Next, some of the tyres came off! When I did obtain the 'best' combination, when asking a loco (a big loco) to haul a very heavy train at speed, not long after starting its rake, one of the drivers (maybe more) slipped on its axle, and the rods got mangled! After putting the thing away in frustration, returning to it some months later, all the tyres had rusted! 

 

There are other issues - quartering for one. No matter how many chassis I've made (and it's well over 500 now), I find that I have to put the drivers on and take them off a few times before I'm happy that all is well (this has nothing to do with the wheels, just my chassis assembling). With Romford/Markits, this can be done thousands of times without the wheels losing their quartering and 'grip' on their axles. My experience with friction-fit drivers is that one usually gets 'one-shot' at this essential-for-good-running process - with huge luck, two. After that, forget it - the wheels are loose on their axles! I know that many modellers who use friction-fit drivers 'set-up' their chassis using Romford/Markits' drivers as a form of 'jig', even those who model in P4. 

 

I came to the conclusion, all those years ago that if I wanted to use friction-fit drivers with total success I'd need to do several things. These being - buy far more wheels than needed for a particular loco in the hope that (eventually) I'd find a 'matched-set'. Once that was achieved, glue the tyres back on where they'd fallen off. Happy with that, then devise some way of 'locking' the wheels on to their axles once they'd been quartered, in the hope that that would prevent their shifting on those axles under load. Also ensure there was not the slightest dampness anywhere near the wheels. This last point is very important; it's axiomatic that dampness should not be present near any model railway, but I built one in a garage years ago. Though dry, the garage was not centrally-heated and any loco with steel tyres (or rolling stock as well) just got rust on them. The axles (also steel) being oiled, didn't suffer in this respect. 

 

For 'total success' with Romford/Markits, none of the measures above need be applied. Quartering is a doddle, the wheels can go on and off without any loss of function, the tyres never fall off (or go rusty) and wheels never slip on their axles. All of this costs, of course!

 

Are Gibson drivers superior in appearance to the latest Markits' ones? Mark Arscott now makes bespoke drivers for individual classes, not just generic ones. 

 

Regards,

 

Tony. 

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I have a mixture of wheel types on my locos. Many were built when Markits didn't have anything other than generic wheels.

 

I have enough that run well on plastic centred wheels to know that it is possible but I have experienced many of the problems that Tony W has listed.

 

"Valour" isn't finished yet but has already had 3 sets of wheels, as two plastic centred sets were impossible to get running true. It now has Markits and is as smooth and steady as anybody could wish.

 

Nowadays, if Markits do the wheel I want, I will use it. If they do one pretty close, such as the wrong crankpin position, I will live with that rather than use plastic centred ones that are spot on.

 

If I have to use plastic centred ones, I build the loco using the nearest equivalent Markits/Romford set from my stash during construction. The plastic ones only go on right at the end, hopefully only once.

 

When I build a loco for somebody else, I will always try to steer them towards using Markits wheels and if they don't want to, I will always say that I can't guarantee that the loco won't have a bit of a wobble as it goes along!

 

I know there are people who put new centres into plastic wheels, re-drilling the axle holes with machine tools. That works but it is beyond what I can comfortably do.

 

Ultrascale are an honourable exception. Their range is limited but the quality is superb. They are as true and smooth a running wheel as I have seen.

 

 

 

 

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7 hours ago, St Enodoc said:

I use T-Cut but with a cocktail stick whittled to a chisel end rather than the oft-recommended cotton bud. I find that gives me more control and lets me see what I'm doing more easily.

These are what I use when a normal cotton bud is too big for the job.

 

You do go through them fairly quickly when using T-Cut, though.

 

John

P1040274r4m.JPG

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2 hours ago, Tony Wright said:

not long after starting its rake, one of the drivers (maybe more) slipped on its axle, and the rods got mangled!

 

One wonders why they don't offer axles with splined ends.


The above problem is something seen on some N gauge models - particularly early Dapol tank locos. By contrast Farish used similar wheels, but the key difference being that the axle ends were splined (and still are on the most recent models). This stops any chance of slippage.

 

Cheers,

Alan

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15 hours ago, Tony Wright said:

Looks much better, Tom,

 

Has the vacuum ejector pipe broken on your model?

 

Regards,

 

Tony. 

 

I think it does enhance the front view of the V2. Bit more work to do but getting there.

 

The vacuum ejector pipe is broken, (semi-deliberately) which was a by product of me preparing the 2 halves of the model. I'll fix it before one final coat of primer to check all is well.

 

Like you, I've moved the model forward about 1mm on the chassis, and I also need to do some work on the splasher tops as well, to fill in a few gaps.

 

EDIT: Does anyone have any pictures of the splasher tops on a V2? Would help me greatly!

 

EDIT2: I've found a couple of pictures in Yeadon PP43-44 and 65, did the splasher top join the top of the chassis/boiler or was there a gap so the wheels would have been visible from behind the splasher plate?

Edited by grob1234
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2 hours ago, Tony Wright said:

I'm glad to explain my reasons for disliking friction-fit driving wheels, Jack.

 

Granted, my experiences are from several years ago and the prejudices I developed then are far too entrenched now. I'll also state that I've never used Ultrascale's wheels.

 

For 'total success' with Romford/Markits, none of the measures above need be applied. Quartering is a doddle, the wheels can go on and off without any loss of function, the tyres never fall off (or go rusty) and wheels never slip on their axles. All of this costs, of course!

 

Are Gibson drivers superior in appearance to the latest Markits' ones? Mark Arscott now makes bespoke drivers for individual classes, not just generic ones. 

 

Regards,

 

Tony. 

Hi Tony,

 

I can't disagree with anything you have said but as someone who universally uses plastic centred wheels I feel I can hopefully provide a balance to your statements.

 

I agree with Mr Gee that Ultrascale wheels are built to a very high standard and are not subject to many of the issues that you have mentioned.  Gibson wheels by comparison have improved significantly since the new owner took over the business but they are still not perfect.  Eccentricity remains a problem with Gibson wheels albeit minor by compartison to before.  I would definitely steer away from using them in combination with a rigid chassis because the inevitable  outcome of combining the two will be problems with maintaining electrical continuity between wheels and track.  If you build a compensated or sprung chassis then the eccentricity in Gibson wheels is imperceptible under normal running conditions. and wont impact electrical continuity.

 

Whilst I could be frustrated by the problem with the tyres coming loose on Gibson wheels, and whilst I wish the new owner had modified the design to avoid it happening, in reality I have never had this happen on a finished model only whilst I've been building them.   Typically it happens to me when I am soldering electrical shorting wires to the tyres which causes them to expand and separate from the plastic centres if I'm not fast enough with the iron.  If they do come loose it is any easy repair with some epoxy resin so its not the end of the world when it happens.

 

Like Tony I fit and refit wheels during the build process but I haven't had the same issue with wheels becoming increasingly loose on their axles.  I think there are two things to understand here.  Firstly it is critical you remove the sharp machined edge to the axle by taking the corner off with fine wet and dry.  It doesn't need much, certainly if you can see the difference you've gone too far, so just enough to be able to feel the difference is sufficient. If you leave the sharp edge this can then cut into the plastic when you fit the wheel on the axle.  IF this happens then you will have problems!  Secondly the plastic has a memory.  If you remove the wheel and then quickly refit it to the axle it will feel looser, but after a few minutes the plastic will return to its original size and will once more grip the axle more firmly.  As a rule I always fit the shorted wheel permanently to the axle with Locktite to avoid disturbing the shorting wire.  It is the wheel at the other side that gets fitted and refitted during the build process.  This wheel is only finally fitted with Locktite during the final assembly.  I have only once had a wheel which has been fitted with Locktite slip on its axle and only because the wheel hub itself had cracked/split. 

 

There are at least two significant plus points for using plastic centred wheels in my opinion.  Firstly the wheels are narrower than an equivalent Markits's wheel.  In EM and P4 this can be the difference between fitting the wheels inside unmodified splashers and also avoiding the front crankpin from hitting the back of the crosshead in an outside cylinder locomotive.  Mr Wright's solution to the crosshead problem is to change the position of the slidebars in their cylinders to gain more room.   The second is a visual benefit.  The flat centre drilled axle of a plastic wheel looks far nicer than those horrible nuts used on Markit wheels.  Markit wheel nuts are one of my personal pet hates but I know that many are not at all bothered by them.

 

As to Tony's comment about rust, I'm not sure how to respond... Ultrascale wheels have n/silver tyres so this will not be a problem.  Tyres are not the only steel parts of a typical model.  As well as the axles there are also buffer heads and I use steel handrail wire.  These steel parts are not unique to locomotives and other roilling stock can be equally effected.  Damp is definitely the enemy of model railways particularly of wooden base boards which swell in damp conditions.  This can in turn lead to track misalignment at the board joints and uneven track if the track bed starts to swell.  My advice is to avoid damp locations for your model railway altogether.

 

So in summary, the use of plastic wheels whilst not quite as simple as using Markit wheels, is still a practical way forward with a bit of care and forethought.  If you want to keep things simple and you model in OO then Markits is the way to go, but if you want to model in EM or P4, or you dislike Markit wheel nuts then plastic ccentred wheels may be the way to go.

 

Regards,

 

Frank

 

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15 minutes ago, jamie92208 said:

I'm fairly sure that the splasher tops finish an inch or so from the boler. I think I took some detail photos of Green Arrow for a model engineet friend,. I will have a look.

 

Jamie

 

Thank you Jamie, that would be very helpful. I think as often is the case the problem is that the OO frames are obvioulsy narrower than the real ones, hence my discrepancy. But if I can fudge it, so it looks a bit better that is good enough.

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Thanks for the comments on friction-fit wheels.

 

Since I don't use compensated/sprung chassis, then I cannot tolerate any 'bobbing' up and down caused by eccentric wheelsets.

 

It looks as well as if some of these plastic-centred driving wheels need modification before they'll run to satisfaction. I find this a bit odd; that a product has to be altered before satisfaction with the running is guaranteed. I know some have said they've encountered a 'tightness' in fitting Romford/Markits wheels on to their axles, but I've not found this in the thousands I've used. 

 

And, if a chassis ever needs dismantling, the Romford/Markits system allows the driving wheels to be removed with relative ease (and put back again).

 

Speaking of the need to dismantle chassis.................

 

2135145410_KsC1.jpg.8b72f537e18f1d942936569f603e4d13.jpg

 

A friend built this K's C1, but was stumped in getting the thing to run satisfactorily. Clearly, he's employed Romford drivers, but it was a bit of a dud. Anyway, now with a DJH motor/gearbox and my giving it a tweak or two with the frames, it now runs superbly.

 

14mm bogie wheels were supplied, but there was no way these would fit. The bottom of the footplate just rode on the K's flanges. With a bit of hacking (literally) I got it to run on the straight with the K's bogie wheels, but as for going around a bend (even of huge radius), forget it. I've substituted 12mm Romford/Markits bogie wheels, and it now goes around curves down to 2' 6". A fair bit had to be taken off the front of the frames as well, and the judicious smearing of a thin layer of Araldite was also necessary. 

 

Has anyone out there made a K's C1 work with correct-sized bogie wheels? 

 

There are a few bendy bits which my friend needs to sort out (nothing to do with me), but this now romps round LB on a dozen kit-built cars. 

 

I believe the RTR C1 has smaller bogie wheels than scale..................

 

Edited by Tony Wright
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5 hours ago, Chuffer Davies said:

Hi Tony,

 

I can't disagree with anything you have said but as someone who universally uses plastic centred wheels I feel I can hopefully provide a balance to your statements.

 

I agree with Mr Gee that Ultrascale wheels are built to a very high standard and are not subject to many of the issues that you have mentioned.  Gibson wheels by comparison have improved significantly since the new owner took over the business but they are still not perfect.  Eccentricity remains a problem with Gibson wheels albeit minor by compartison to before.  I would definitely steer away from using them in combination with a rigid chassis because the inevitable  outcome of combining the two will be problems with maintaining electrical continuity between wheels and track.  If you build a compensated or sprung chassis then the eccentricity in Gibson wheels is imperceptible under normal running conditions. and wont impact electrical continuity.

 

Whilst I could be frustrated by the problem with the tyres coming loose on Gibson wheels, and whilst I wish the new owner had modified the design to avoid it happening, in reality I have never had this happen on a finished model only whilst I've been building them.   Typically it happens to me when I am soldering electrical shorting wires to the tyres which causes them to expand and separate from the plastic centres if I'm not fast enough with the iron.  If they do come loose it is any easy repair with some epoxy resin so its not the end of the world when it happens.

 

Like Tony I fit and refit wheels during the build process but I haven't had the same issue with wheels becoming increasingly loose on their axles.  I think there are two things to understand here.  Firstly it is critical you remove the sharp machined edge to the axle by taking the corner off with fine wet and dry.  It doesn't need much, certainly if you can see the difference you've gone too far, so just enough to be able to feel the difference is sufficient. If you leave the sharp edge this can then cut into the plastic when you fit the wheel on the axle.  IF this happens then you will have problems!  Secondly the plastic has a memory.  If you remove the wheel and then quickly refit it to the axle it will feel looser, but after a few minutes the plastic will return to its original size and will once more grip the axle more firmly.  As a rule I always fit the shorted wheel permanently to the axle with Locktite to avoid disturbing the shorting wire.  It is the wheel at the other side that gets fitted and refitted during the build process.  This wheel is only finally fitted with Locktite during the final assembly.  I have only once had a wheel which has been fitted with Locktite slip on its axle and only because the wheel hub itself had cracked/split. 

 

There are at least two significant plus points for using plastic centred wheels in my opinion.  Firstly the wheels are narrower than an equivalent Markits's wheel.  In EM and P4 this can be the difference between fitting the wheels inside unmodified splashers and also avoiding the front crankpin from hitting the back of the crosshead in an outside cylinder locomotive.  Mr Wright's solution to the crosshead problem is to change the position of the slidebars in their cylinders to gain more room.   The second is a visual benefit.  The flat centre drilled axle of a plastic wheel looks far nicer than those horrible nuts used on Markit wheels.  Markit wheel nuts are one of my personal pet hates but I know that many are not at all bothered by them.

 

As to Tony's comment about rust, I'm not sure how to respond... Ultrascale wheels have n/silver tyres so this will not be a problem.  Tyres are not the only steel parts of a typical model.  As well as the axles there are also buffer heads and I use steel handrail wire.  These steel parts are not unique to locomotives and other roilling stock can be equally effected.  Damp is definitely the enemy of model railways particularly of wooden base boards which swell in damp conditions.  This can in turn lead to track misalignment at the board joints and uneven track if the track bed starts to swell.  My advice is to avoid damp locations for your model railway altogether.

 

So in summary, the use of plastic wheels whilst not quite as simple as using Markit wheels, is still a practical way forward with a bit of care and forethought.  If you want to keep things simple and you model in OO then Markits is the way to go, but if you want to model in EM or P4, or you dislike Markit wheel nuts then plastic ccentred wheels may be the way to go.

 

Regards,

 

Frank

 

 

You make a point there Frank that I hadn't really thought about until you mentioned it.

 

If you have a wheel that is less than concentric, in a rigid frame the loco body will indeed all move around.

 

With compensation or springing the axle can move up and down but the movement of the body is minimised or may even by removed altogether.

 

Looking back at the past, one of the leading figures promoting compensation and also a leading supplier of plastic centred wheels for many years was the late great Mike Sharman. A super engineer with great skill.

 

Perhaps his development of both the wheels and compensation went hand in hand and using the wheels in rigid mechanisms was not what he intended.

 

Edit to add that all the Gibson and Maygib kits were designed to be built sprung too. A pattern begins to emerge!

 

 

Edited by t-b-g
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On the subject of wheels, I have had issues with the Markits wheels I used for my North British shunter and also for the Hudswell Clarke tank I am building at the moment. Many of the wheels simply would not fit properly on to the axles, resulting in a serious lack of squareness. Putting them in a vice helps somewhat, and thankfully damage has been avoided so far.

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