OO gauge GWR Mogul and Prairie

[Izzy]

The issue with the gear ratio is not the idler gear as such but the small size of the final gear on the driven axle. It is this that needs to be bigger, have more teeth on it relative to the other gear on the first stage shaft. So the idler gear needs to either be smaller or got rid of altogether. Whatever, different shaft distances would be needed for the idler if retained. I can’t really see how the gearing can be altered without a new chassis arrangement. 

[Miss Prism]

17 hours ago, Miss Prism said:

I can't recall seeing a pic of a WWI Mogul in ROD livery.

 

Silly me:

https://didcotrailwaycentre.org.uk/shopimages/sections/normal/1 5322 France 3 October 1918.jpg

(from https://didcotrailwaycentre.org.uk/article.php/436/going-loco-november-2020 )

 

[Robert John Davis]

18 hours ago, MatthewCarty said:

Problem with your argument is this is prototypical for preservation. Plus it’s a different colour which makes it stand out from all the other black/green ones. I don’t think you’ll convince Dapol to change this, best chance is to hope this one sells well then ask for another in grey/black.

 

 

I don't know if it's a problem as much as it's something to consider the sales value of. 

 

Which would sell more?

 

a) #5322 in a khaki livery that it wore at a museum for a few years (but likely never before)

 

b) A #43xx in proper ROD black livery

 

And do note, if wearing a livery that's prototypical for the preservation era is a factor, the good folks at Didcot painted the locomotive in proper ROD black which  she's wearing now. Therefore, the preservation argument applies to both khaki and black.

 

https://didcotrailwaycentre.org.uk/article.php/72/5322-43xx-class

 

Given the interest in WW1 era models as of late, the correct answer may be a moving target.

 

The whole khaki paint thing is quite contentious in some circles. For me, I don't really care if there were a few ROD locomotives painted that way (although some evidence could change my mind), the upshot is that all reliable information points to black being the standard, so that's what I go for. 

 

Some of the major manufacturers have selected the (likely) erroneous khaki. How have they sold?  I would bet Oxford sold more due the enticing pairing of the kahaki Deans Goods with the railway gun. I would also bet Bachmann sold more of the khaki "City of Birmingham" since it came with the ambulance train. Thankfully Bachmann released the Robinson 2-8-0 in correct ROD black, perhaps seeing a trend in the successful (and accurately painted) 009 WW1 models? All of that's conjecture, of course. 

 

There are plenty of instances where manufacturers changed or dropped liveries because low reservations. If the khaki locomotive doesn't garner pre-order interest, it may help Dapol to know that there are customers out there who would pop for a black one. 

 

I have contacted Dapol, not to criticize them, but to express interest in an alternative. If enough of us are like-minded (and if khaki pre-orders are low) maybe we will get a black ROD version?

 

If not, I won't lose any sleep over it, but I also won't be ordering one. 

 

Rob

 

 

 

 

 

 

 

 

Edited March 16, 2021 by Robert John Davis
added a link

[Paul.Uni]

40 minutes ago, Robert John Davis said:

And do note, if wearing a livery that's prototypical for the preservation era is a factor, the good folks at Didcot painted the locomotive in proper ROD black which  she's wearing now. Therefore, the preservation argument applies to both khaki and black.

IIRC 5322 didn't carry ROD Black while it was operational in its last ticket, so I can't justify a model of it in ROD Black. I can justify one in the liveries it carried, which are ROD Khaki and BR Black with Early Crest.

Edited March 16, 2021 by Paul.Uni

[Welchester]

18 hours ago, Miss Prism said:

 I can't recall seeing a pic of a WWI Mogul in ROD livery.

 

1 hour ago, Miss Prism said:

Silly me:

https://didcotrailwaycentre.org.uk/shopimages/sections/normal/1 5322 France 3 October 1918.jpg

(from https://didcotrailwaycentre.org.uk/article.php/436/going-loco-november-2020 )

 

There's this too.

[57xx]

On 16/03/2021 at 10:41, Izzy said:

The issue with the gear ratio is not the idler gear as such but the small size of the final gear on the driven axle. It is this that needs to be bigger, have more teeth on it relative to the other gear on the first stage shaft. So the idler gear needs to either be smaller or got rid of altogether. Whatever, different shaft distances would be needed for the idler if retained. I can’t really see how the gearing can be altered without a new chassis arrangement. 

 

It's not an idler gear. Idler gears do not alter gears ratios, this one has two set of teath and is reducing the gear ratio between the motor worm and the gear on the axle. If you increase the teeth on the axle gear and reduce the teeth on the output side of the intermediate gear appropriately (which is pretty much what you said, but it's not an either/or), you can change the ratio and keep the same shaft spacing.

[Robert John Davis]

21 hours ago, Paul.Uni said:

IIRC 5322 didn't carry ROD Black while it was operational in its last ticket, so I can't justify a model of it in ROD Black. I can justify one in the liveries it carried, which are ROD Khaki and BR Black with Early Crest.

 

 

Interesting and insightful. Thank you. 

[1466]

I apologise in advance for going slightly off topic . I recall visiting Didcot and a delightful female volunteer invited  me up to the cab of 5322 where she was cleaning brass .Once there ,  she showed me the brackets  which held a rifle in each side , a reminder that ROD members were  soldiers as well as railwaymen . 
My grandfather was in the ROD so I feel a special connection .

[melmerby]

On 15/03/2021 at 21:29, Chuffer Davies said:

Hi Keith,

Out with the screw drivers again and here is the result so you can see for yourselves:

From the top:

You can see that the pinion for the worm is paired with a 2nd gear that transfer drive to the idler gear below.
From below:

The idler gear is definitely not paired with another and is therefore just a transfer gear directly to the final drive gear.

 

Regards,

Frank

57XX said

"It's not an idler gear. Idler gears do not alter gears ratios, this one has two set of teath and is reducing the gear ratio between the motor worm and the gear on the axle. If you increase the teeth on the axle gear and reduce the teeth on the output side of the intermediate gear appropriately (which is pretty much what you said, but it's not an either/or), you can change the ratio and keep the same shaft spacing."

 

Hi 57XX

Thanks to Chuffer (Frank) we can see that there is an idler between the double pinion driven by the motor worm and the axle gear

Edited March 17, 2021 by melmerby

[Mallard60022]

Apologies fellow owners but can anyone link me to a post where someone has improved the silly push fit connector for the loco tender for the 63XX. I thought mine was OK but nope it is useless now. I have an idea to fit an additional draw bar/connector. Poor design I am afraid to say, in hindsight of course.

Thank you.

Phil 

[89A]

I find it unusual that on the sound fitted versions although fitted with a Zimo MX658N18 decoder there does not seem to be a physical braking function.

 

Normally on Zimo this is on F2. On these F7 gives braking sounds but does not physically slow down the loco.

 

AFAICT.

[boxbrownie]

1 hour ago, 89A said:

I find it unusual that on the sound fitted versions although fitted with a Zimo MX658N18 decoder there does not seem to be a physical braking function.

 

Normally on Zimo this is on F2. On these F7 gives braking sounds but does not physically slow down the loco.

 

AFAICT.

Pretty sure it entirely depends upon whoever wrote the sound file on the chip as to whether they include that function or not.

[PeteN92]

2 hours ago, boxbrownie said:

Pretty sure it entirely depends upon whoever wrote the sound file on the chip as to whether they include that function or not.

For that matter have Dapol ever said what sound project is on the chip / who it was done by I can't imagine it was done in-house?

[Gopher]

13 minutes ago, PeteN92 said:

For that matter have Dapol ever said what sound project is on the chip / who it was done by I can't imagine it was done in-house?

Pretty sure it is Mr Sound Guy, so not an in house project.

[Opelsi]

Renumbering suitability enquiry.

 

Please could anyone advise me on the suitability of my 6336 to be renumbered as preserved 9303?

 

I also really like the idea of getting 4321 with a view to changing that to other preserved example 5322 and wondered if that might be suitable too please?

 

Appreciated positive comments from those with far more knowledge than I.

[Pteremy]

So far as 6336 is concerned, no suitability - 9303 is one of the final batch built with more modern Collett cab. Hopefully Dapol will do this version eventually.

[Butler Henderson]

Also hoping for the Collett cab version by which time Dapol will be probably on the nth version of the chassis each being the best thing since sliced bread when announced.

Edited March 20, 2021 by Butler Henderson

[The Johnster]

The 4321-5322 conversion is a goer, not much more involved than changing the number and a re-livery if you want, but the 6336-9303 is less straigtforward.  9303 had the front end lightened when it was rebuilt as  7325 in 1958, so the ballast weight behind the buffer beam would need to be removed, and of course there's the Collett side windowed cab.  This is deceptive, as although most Collett cabs look very similar, they were in fact bespoke to the class they were fitted to, so you would not be able to use one from a Manor, Grange, or 2884 for example.  Scratchbuilding is possible of course, but one would need a 93xx/73xx drawing to work from. 

 

A 93xx/73xx cab from a Mainline donor loco is not suitable either, as the firebox of these locos was enlarged to accommodate the pancake motor and spur gears, so the firebox cutout in the cab front sheet is wrong and will be too large for a Dapol derived loco.  Probably best to wait for a Collett Cab Dapol; I'm sure one will turn up eventually as Dap like to cover all the bases with their locos.

 

Sorry; I know that's not what you wanted to hear!

Edited March 20, 2021 by The Johnster

[Les1952]

4 hours ago, The Johnster said:

.  This is deceptive, as although most Collett cabs look very similar, they were in fact bespoke to the class they were fitted to, so you would not be able to use one from a Manor, Grange, or 2884 for example. 

 

 

That's GWR standardisation.....

 

[The Johnster]

Exactly; all GW locos are the same.  Except when they’re different. 

[Opelsi]

16 hours ago, The Johnster said:

The 4321-5322 conversion is a goer, not much more involved than changing the number and a re-livery if you want, but the 6336-9303 is less straigtforward.  9303 had the front end lightened when it was rebuilt as  7325 in 1958, so the ballast weight behind the buffer beam would need to be removed, and of course there's the Collett side windowed cab.  This is deceptive, as although most Collett cabs look very similar, they were in fact bespoke to the class they were fitted to, so you would not be able to use one from a Manor, Grange, or 2884 for example.  Scratchbuilding is possible of course, but one would need a 93xx/73xx drawing to work from. 

 

A 93xx/73xx cab from a Mainline donor loco is not suitable either, as the firebox of these locos was enlarged to accommodate the pancake motor and spur gears, so the firebox cutout in the cab front sheet is wrong and will be too large for a Dapol derived loco.  Probably best to wait for a Collett Cab Dapol; I'm sure one will turn up eventually as Dap like to cover all the bases with their locos.

 

Sorry; I know that's not what you wanted to hear!

 

Much appreciated information. I will go for the 4321-5322 conversion in due course.

[Guest]

On 20/03/2021 at 16:24, The Johnster said:

..... but the 6336-9303 is less straigtforward.  9303 had the front end lightened when it was rebuilt as  7325 in 1958, so the ballast weight behind the buffer beam would need to be removed, and of course there's the Collett side windowed cab.  This is deceptive, as although most Collett cabs look very similar, they were in fact bespoke to the class they were fitted to, so you would not be able to use one from a Manor, Grange, or 2884 for example.  Scratchbuilding is possible of course, but one would need a 93xx/73xx drawing to work from. 

 

A 93xx/73xx cab from a Mainline donor loco is not suitable either, as the firebox of these locos was enlarged to accommodate the pancake motor and spur gears, so the firebox cutout in the cab front sheet is wrong and will be too large for a Dapol derived loco.  Probably best to wait for a Collett Cab Dapol; I'm sure one will turn up eventually as Dap like to cover all the bases with their locos.

 

Sorry; I know that's not what you wanted to hear!

OMG. Rivet counters. Thought these died out when I was 14, and wondered what RC meant when read in my first 'Railway Modeller' (Kemble & Tetbury R of TM, to be precise) , errrr....., that was in 1971, can you really tell the difference at normal viewing distance, never mind were still alive.

Edited March 21, 2021 by Guest
spelling

[Jack P]

1 hour ago, confused said:

can you really tell the difference at normal viewing distance

 

You could probably tell if the cab did, or did not have a side window from standard viewing distance, yes. 

 

Also, C'mon.. It's not really fair to derogatorily call The Johnster a rivet counter, someone asked for accurate advice in regards to renumbering something, and the information provided is concise and directly relevant to the request. The input of prototype knowledge should be relished, not ridiculed. 

[The Johnster]

Thank you Jack.

 

I try to get things as right as I reasonably can within my limited abilities, but I've never been called a rivet counter before; I've decided to take it as a compliment, albeit unjustified, to my erudition and modelling prowess... I don't really think that 'rivet counter' is a term that can be applied to someone whose layout features, amongst other offences against finescalery, a Hornby 2721 (worked up to get rid of the upside down flowerpot chimney and the rather wierd safety valve cover, with a Bachmann chassis that does not match the splashers and has the wrong type of coupling rods) and a couple of K's A31 auto trailers, the last word in crude and blobby detail.  And I use setrack curves in the fiddle yard, and have tension lock couplers on my stock!

 

I will accept all sorts of 'layout model/3 foot rule' incorrectness up to a point, beyond which I am uncomfortable, but would not criticise anyone whose 'point of discomfort' is different to mine.  I don't have any Hornby 16ton minerals for example because they are on an incorrect chassis with the wrong wheelbase, so I buy Bachmanns, which are correct, or Parkside kits. 

 

Opelsi asked a question which I answered as best I could in the spirit of advice regarding what conversions were or weren't possible by what I would consider normal modelling standards.  A finescale scratch builder is probably not going to be buying RTR locos anyway; seemed likely to me that Opelski just wanted to know what was invovled in using the RTR Dapol mogul to represent his particular desired prototypes. 

 

The appearance of a GW mogul with a Collett cab is very obvious from much more than normal viewing distance even at a glance, the general proportions of the loco looking very different from the Churchward cab version.  Would you consider that a Castle cab would be acceptable on a Star?  I would agree that some of the other differences, such as the ballast weight behind the front buffer beam, are less instanteously obvious and have to be looked for.

[melmerby]

I wonder how different the various Collett cabs on models are.

I've just checked the Dapol mogul's current cab against a Mainline mogul cab, a Bachmann 2251 cab and a Bachmann Hall cab and they are pretty close,(I haven't checked against the Mainline or Bachmann Manors yet) I reckon you could get away withs some cut & shut if you wanted to.