nswgr1855

The facts were made clear to them over 10 years ago. Cheers, Terry.

Hello Andy, Actually there is a problem with the NMRA standard and its 14.61mm Max for many RTR H0 wheels. If the wheel flange is wider than 0.59mm the wheels have a good chance of derailing on most RTR track. Most H0 wheels have a wider flange, and the NMRA RP 25 110 flange is a nominal 0.76mm. Of course if you build track to the NMRA standard, no problem if you like the wider flange way gaps and wide wheels. Cheers, Terry Flynn.

Gentlemen, A bit late but here is my explanation as to the different track minimum dimensions in the fine tolerance AMRA standard. 16.2mm is minimum track gauge allowed any where. The maximum track gauge allowed any where is 16.8mm, the same as NOROP. These are refereed to in the AMRA standard as limits. The average of these dimensions is 16.5mm, that is the nominal H0 / 00 value. Now you can have your track any value between the limits and get reliable running. Gauge widening is not a problem, If you stick to the AMRA minimum radius standard. You can build a crossing V with the minimum of 16.2mm and fully comply with the standard. It would simply mean you have different flange way values compared to the recommended AMRA values. If you build your track to the 00-SF / EM-2 standard, you are complying with the AMRA standard. The "RECOMMENDED" AMRA minimum track gauge for FINE TOLERANCE crossing V's is 16.25, and the maximum is 16.3mm. This range allows flange ways between 1mm and 1.05mm. These values allow for a practical tolerance and results in dimensions suitable for V and K crossings. Its long proven the standard results in derailment free smooth running with most RTR H0 and 00 models. I have successfully built diamond crossings with curves in them which I can push 30 4 wheel wagons through without any derailments. I have run a model of a Lima TGV Duplex at scale 200+Kmh pushing and pulling. Yes Martin is 100% correct, the check gauge is critical, at 15.2mm minimum for track. This is the check gauge PECO uses. Unfortunately the NMRA decided to make their check larger and this has mislead many to publishing and using standards that are not compatible with the majority of RTR track manufacturers. The original NMRA track check gauge was 0.6" =15.24mm, close enough not to be a problem. Cheers, Terry Flynn.

I have just uploaded a replacement leading bogie for the 00 scale Hornby P2 locomotive. Further details are at https://www.shapeways.com/product/25V9WVEED/lner-p2-leading-bogie?optionId=153614972&li=marketplace

From experience assuming free rolling carriages and locomotives with no spring on the leading or trailing trucks, using 3 foot radius curves, you need to ease the gradient by multiplying your prototype gradient by 1.75 if you want to run the maximum length prototype train length. For example a prototype grade of 1:40, you multiply 40 x 1.75 = 70. Therefore use a 1 in 70 grade on your 3 foot curve. I have found on straights or prototype curves , you can use the prototype grade with plastic bodied RTR, as long as you remove springs from leading and trailing trucks, and adjust the centre of gravity of the loco, adding or removing mass if necessary. Terry Flynn.

It depends what the longest item carriage or locomotive that you wish to couple them to. The minimum radius is about 6 times the length of your equipment for no buffer lock. Terry Flynn.

It's viable as are the extra coaches added to the project Terry Flynn

I already have one! Terry Flynn.

No tooling exists at the moment as far as I am aware, so changes to the project are cheap to do. A new roof and ends is not a modification to existing tooling, but a modification to the proposed tooling. Yes it is a different design, but the same tool with extra parts would be used. I'm still talking about a generic coach, not a finescale coach. Terry Flynn.

Sorry to mislead you into thinking Australia manufactures any RTR model railways these days. Only cottage industry model railway stuff is done here. The 5000 pound extra tooling cost is based on H0 models produced in the last year in China. Manufacturing of RTR today is cheaper in real terms due to computeriseration. 3D cad drawings are cheap to change and easy to check if you have the skill. CAD CAM combined with CNC machining makes it quicker and more accurate to machine. Chinese labor is still relatively low cost. Although the cost to produce an injection moulded kit is less than for RTR tooling the market is minimal compared to RTR and not an efficient way of making any money. It's not a big cost for Hattons to get a quote for extra roofs at the moment. Even if the extra cost is 10,000 pounds it still is a minimal cost increase per wagon sold. Terry Flynn.

An estimate based on costs for an Aussie company to modify existing tooling of similar complexity. Terry Flynn.

Although I always prefer accurate models, in this case I have been suggesting that a GNR roof profile and ends be done, using the generic tooling . That would result in generic models with a GNR roof. The extra cost to do this could be as low as 5,000 pounds to do the 6 wheel coach roof and ends . Considering there would be over 2000 RTR Stirlings , and we assume 500 Stirling owners buy 7 generic 6 wheel coaches (based on a picture published in Single Wheeler Locomotives by Charles Fryer) then the extra cost per GNR 6 wheel coach is only 15 pence. Terry Flynn.

Well if you had read what I have said I have been actually suggesting they spend a little more and do the correct roof for GNR, still using the existing generic sides and under frame. Then the GNR repaints would look closer to prototype from a 2m viewing distance. Terry Flynn.

There is very little that is generic in a repaint that looks nothing like the prototype it is supposed to represent. The current proposed Hatton project is inappropriate for a number of railway companies, the GNR being one of them. You could consider the terms false and misleading to describe the GNR version as generic. Terry Flynn.

I consider the terms fine and coarse to refer to the tolerance the designer has decided to apply to the scale they are using. Thus coarse models deviate considerably from nominal dimensions, and fine means the deviation from the nominal dimensions is smaller, therefore closer to scale overall. A basic concept many seem to have difficulty with. Terry Flynn.

I have consistently stated to do more than one roof profile. That means more coaches that look right. Kits are irrelevant to RTR sales. I have no intention to purchase unmade UK kits. I have enough unmade NSWGR H0 kits to satisfy my kit building urges. Terry Flynn.

No I will be happy if they do a GNR shaped roof for their generic GNR coaches. Closer to prototype means more sales. Terry Flynn,

Did you ask them about doing different roof styles? Terry Flynn.

The problem for me is the Hattons offering does not have the characteristic roof profile of the GNR, thus they are unacceptable for those of us non experts who have noticed this significant easily observed difference. They will loose sales because of this. Fine scale means its not coarse scale. Cheers, Terry Flynn.

Then I assume that you will not be buying any of the Hattons offerings, unless they are accurate representative of the prototype you model. I will not be buying any Hattons GNR repaints unless they look like a GNR coach. To look like a GNR coach they need the correct roof for starters. As for SDS models, they specialise in accurate finescale RTR H0 scale Australian prototype models. The Australian market is a tenth of the UK market yet SDS makes enough money to continue developing new prototype specific finescale RTR models. Terry Flynn.

Well that is what Hattons is not quire offering, They seem to be based on a one company's styling, the rest are just repaints. The Triang clerestories have been offered in incorrect colours for those happy with incorrect models. Terry Flynn.

I disagree. R&D is relatively cheap to do because there are plenty of model railway enthusiasts who will provide this information for next to nothing. It would cost no more to produce a set of accurate coaches for one company and then paint extras the colours of other companies (the generic range). This would result in increased sales of the accurate company models, and the same sales for the 'generic' repaints. Terry Flynn.

Adding extra roof profiles will not double the cost of tooling, as you still could have the same number of tools, with only extra cavity mould inserts for the roof and ends. I know this because I am good friends with the design engineer for SDS models http://www.sdsmodels.com.au . I only consider the roof profile more important than panel moulding simply because from a distance the roof shape is clearly observed. For paneling to be seen, a closer viewing distance is required. I would prefer accurate models, but that is not what is being proposed and that would be an extra cost again. Terry Flynn.

Yes, I understand a correct roof will not make it a close to accurate GNR model, but from a viewing distance of 2m, it should look the part. With the wrong roof as proposed it will look totally wrong. I would prefer the correct paneling on these models, but it appears there is little chance of this happening for this project. Terry Flynn.

Thank you for the prototype information. One assumption you have made is a person purchasing RTR GNR stock is sticking with a particular era and location. In my case my Stirling is simply a model I display on a shelf, and most RTR models are sold to people who are collectors or people who simply run any thing they like on their layouts. I know lots of rail enthusiasts with a room full of models and no layout. It is these groups of model train "collector" who makes up the majority of RTR sales. Terry Flynn.