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Class A3 4-6-2 in O Gauge from Hatton's


Hattons Dave
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Not professing any expertise but the cylinder drain cocks on all versions appear to be the type fitted to 4472 after the first Tony Marchington sponsored overhaul rather than the LNER type appropriate to all A3's (including 4472 pre 2000). 

 

 

I take my hat off to Hattons/Heljan but have also noticed like Mike that much of the model is based on 4472 during preservation. I have been researching Gresley's A1/A3's for over 20 years now for my own build project and so things jump out at me when wrong. I haven't gone over the model with a fine tooth combe but concentrating on the somebox area, the most obvious errors are ...

The somebox tube only suits 4472 after the 80's (can find the exact date if required), no other Gresley pacific (that I'm aware of) had this smokebox, in particular, the row of rivets around the rear of the tube. The front ring (her face) was different too but I can't see it clearly in the Cad drawings.

There is no cover plate around the anti-vacuum valve (snifting valve)? again this is as 4472 is today, this cover varied in shape size, being much larger in A1 guise to a little smaller as A3, but nevertheless, it is prominent.

Where are the front steps?... fitted in 1935, they have changed a little in preservation but not that you would notice on a model of this size.

Not sure what happened when the artist drew the mounting bolts around the ejector elbow but they've grown in number?

The mounting bolts around the single chimney are orientated incorrectly, I suspect the double too but as I'm not building this variant, I'd have to research it a little to be sure.

There are probably others but as I said I've only glanced over the model's front.

 

Please don't think that I'm just 'nick picking'..I'm not...I am a professional model maker by trade and thus have a keen eye for detail......if the model hasn't been put into production yet these little things could be corrected very easily in CAD and make what's going to be a great model into a masterpiece, it just needs a little more research, IMHO of course....:) However, I do appreciate that due to costs Heljan may have concentrated on 4472 as she is today and are just changing liveries and not much in detail to suit other prototypes.

 

kind regards

 

Pete

 

 

.

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I can see where you are coming from. For the price, I dont think any sane person is going to complain although there is always the danger the RTR ex. 4mm guys will expect butter on both sides! Gauge 0 was always a builders scale and I am sure many buyiers will sort out the locos to suit the loco and period they are modelling. I know I would.

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  • RMweb Gold

Hi all,

 

As promised previously, here's some shots of the revised A4 bodyshell for review. Please bear in mind the chimney is added as a representation at this stage. As ever, BIG images available by clicking the thumbnails.

 

Further details are available on the website Here.

 

Cheers,

Dave

 

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So far as I can tell from photographs, the front end should still taper in more. The 'nose' would appear to be about 70% of the width at the bottom compared to at smokebox level.

 

a4%20FRONT_zpsskoe06xb.jpg

 

Giving something more like this, also with the doors narrowed to allow for support framing, and raised to a more correct level (by eye!)

 

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The vallance cut out curve also needs adjustment to make it shallower

 

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Edited by Giles
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Morning all, there is one major thing that everyone is forgetting and I'm rather surprised no-one has picked up on. The side on view of the smokebox casing is also incorrect. Hattons has stated that they've used available drawings for this - if the A4 GA works drawing has been used they will not get it right from that as none of the A4's actually had their casings built to the drawing. Every single one was unique but none were as per the drawing. I should know because I spent two years researching the things for my profile drawings. Worked and modified from the GA as provided by the NRM, this is how it should be - the actual curve of the casing is shallower and less pronounced than that represented by both the works drawings and Hatton's cad. The top portion of the casing underneath the chimney should also be dead flat from the rear of the chimney casing to about 2/3 of the way down the chimney. The section where the nose casing dogs into the bufferbeam is also wrong and not pronounced enough. Unfortunately I can't line them up properly as my phone does not have a photo flip function

 

EDIT: Even more info added

 

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Edited by 60800
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This is the Heljan outline IN RED overlaid on 60800's drawing. The red outline was accurately traced on AutoCAD and then overlaid, so there may be a 1% size difference, but the shape and proportion is bang on to the pictures posted by Hatton's)

 

A4%20Overlay_zpsa9fzs7hu.jpg

Edited by Giles
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I lie a lot..... it comes with living a breathing 08's

Now corrected!

I knew it was different, but not that different, the shape around the bufferbeam is worse than I thought - thanks for doing the overlay, I don't have the software to do it myself unfortunately

 

Cheers,

60800

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Nice to see Hattons taking an active interest in your constructive comments. I've ordered an A3 and an A4 but if the shape of the A4 is wrong I will revert to building a Finney 7 model, not that I want to as I could spend the time building something else. If the shapes right I might even get another A4 so keep the comments coming and help make a superb model.

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Likewise, the shape has to be right.... I've ordered one, but I should of course cancel it if the the body shape is incorrect.

 

Meanwhile, i'm all for being as constructive as possible!

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Keep the constructive comments coming I say, wouldn't it be great to get everyone's agreement on the shape as near as possible and have a spot on model Hattons can be proud of instead of being made to accept something which is irritating i.e. Class 55, 25, 52, Mk1 coaches etc.

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  • RMweb Gold

Hi all,

Thanks for the extensive feedback so far. The streamlining is a hugely complex shape to develop in CAD and we're committed to ensuring it is as accurate as possible (as with every detail on the A3s, A4s and teaks) so any information is always welcome.

Regarding the A4, we do have copies of the GA drawings however these have been used in conjunction with other schematics and full surveys of 4468 and 60009 (as well as the parts available of 60007 while it is dismantled) alongside an ever-growing image archive of all thirty-four members of the fleet.

All of the above comments will be passed onto the CAD development team (as well as our own notes). Once we have further developments I'll post it here again for review.

Cheers,

Dave

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Hi Dave

 

This is just a suggestion as something that I have seen used many times in the making of films, if the CAD guys are struggling with the shape, which I fully understand especially, if as has been pointed out that the works GA drawings are wrong, perhaps using one of the 3D scanner companies out there would solve the issue? These can scan at resolutions down to a couple of microns. I recall when we built the large Antonov aircraft for the Bond film, 'The World is not Enough', the drawings were not available, we got lucky when it visited the UK and production got permission to scan the aircraft, now that was one of the largest in the world so an A4 would be pretty simple in comparison and more available too.

 

Just an idea...:)

 

Pete

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don't some people have interesting jobs...?

 

I mean, I love my job, and it is interesting, and challenging, frustrating, satisfying in roughly equal measure, but "scan that airplane for a James Bond film set" somehow sounds rather exciting...

 

Though this is probably a case of the grass is greener - they were probably on a back-road at Stansted in the rain...

 

 

Pete, what kind of kit did you use, and what did you scan into - a point cloud in 3D CAD?

 

best

Simon

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Hi Simon

 

I didn't scan it myself, I was part of the team that built the larger of the two models used, one (smaller) for flying shots, the other for action...IIRC it was indeed scanned at Stanstead, a specialist team was brought in to do the scanning which is how I know that this service is readily available...this technology is used a lot in film/tv work today...for example, 007's Aston DB5 was scanned for Skyfall, 3D printed too..alas this is what's happening in the industry these days...personally I prefer the hands on approach...:)

 

Pete

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The price for the Locos is really keen making it look good at the moment with the Aus $ faring well against the £ but if the $-to-£ goes back to pre Brexit values by 2018 will be again effectively double in price for us poor Down under cousins.

Would really like a A3 in Apple Green, similar to how Scotsman ran when she visited Australia "atleast I can justify running this on my Ozzy O scale railway".

Plus A4 Commonwealth of Australia would be a nice shelf sitter

Whilst it has worked £-to-$ nicely for the latest Hattons J94 release in OO saving me plenty on the expected price from pre order to delivery.

It's a gamble to know what the real price will be in the future for export sales, not such a big gamble on a £98 OO model but on a couple of O scale £750 loco's

Hmmm what to do.[/quote Would we still get the present tax situation if we prepared?

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  • RMweb Gold

Hi all,

 

Besides the A4, development has continued on the A3 with the tooling production underway. We have received a 3D print of 60103 "Flying Scotsman" as will be produced with double chimney, German smoke deflectors and unstreamlined corridor tender.

 

We've replaced the handrails with brass on this test print and these will be brass on the models as supplied, however every other detail (including the valve gear, couplings and lubricator piping) is as it will be on the model. The print has been produced from the final CAD so all details shown will be present on the model as produced.

 

I'll let the pictures do the talking from here (as ever, click the thumbnails for LARGE images!) but check out the website for further details Here.

 

Cheers,

Dave

 

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I'd be happy to take the 3d print when you are finished with it. It would make up into a great static model in its own right with a bit of sanding down of the grain.Then a full paint job.

Perhaps raffle it off. I can't be the only one thinking this.

Richard

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One thing, (and easily fixed!) The angle of the return crank is too extreme (should be more like 15 degrees or so from the vertical) leading to the expansion link being pushed (and pulled) far too far, as can be seen on your model. It is showing at a more extreme angle than the real thing can ever go. The return crank will typically scribe a circle somewhere around the wheel boss - whereas as shown at the moment it is set at a much wider angle.

 

It is also set BEHIND of the wheel centre, whereas it must be set in FRONT, as is correct with the porting of these locos.

 

Best,

 

Giles

Edited by Giles
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