Up-grading Hornby-Dublo/Wrenn 'Duchesses'

[DCB]

On 14/09/2021 at 21:54, TerryD1471 said:

I have just revisited this site and seen your question. I have used both options; my earliest effort was to drill out the crankpin sockets in the 26 mm Romford drivers sufficiently to accept the H/D-Wrenn crankpins as a force fit, which then held the original coupling rods in place.

 

Later I have used Romford type crankpins together with "homemade" coupling rods &/or Comet rods or rods from kits. The option of using H/D rods with bushes in the holes to accept Romford crankpins has also been used. I think the Romford crank pin option is better since if there is a "binding " problem, it is much more easily solved. Once you have pushed the H/D crank pins into place and found that there is binding, it's far more difficult to solve.

 

My 2 Hornby Dublo Duchess conversions needed their magnet pole pieces filed away to clear Romford 26mm driving wheels.  I used non flanged centre wheels for 2nd Radius with the H/D crank with return crank pressed and loctited into the centre wheel and the rods opened up to take Triang crankpin screws which are a direct fit in Romford wheels in the leading and trailing wheels.

Wheels on the insulated side need small washers, the rim from Romford top hat pinpoint axle bearings, to stop the rods shorting on the wheel centres.   For DCC insulate both sides and use washers both sides.

Despite needing flangeless centre wheels mine runs scale distance between loco and tender of around 2mm.   Like most H/D Duchesses mine was low at the cab end, even with 26mm wheels, so some packing was required to line up the tender footplate with the loco. I think I used 16mm Jackson tender wheels and I drilled holes in the baseplate above the wheels for flange clearance. Getting the tender to match the engine is tricky, the two don't line up like GWR locos but the  top of the locos footplate aligns with the flange on the bottom of the Tender tank and the cab roof with the tender bulkhead, but the close coupled correctly aligned tender makes a huge difference to these locos.   Several pictured in this thread need attention IMHO

The H/D Duchess draw bar is useless and bears down on the pony truck lifting the rear drivers, Changing it for the Wrenn City type approx doubles pulling power.  I cut away the drawbar slot under the cab and I use a double jointed drawbar which pulls on the pony truck frame not the chassis and improves stability but means it can't propel stock around S bends any more.   However it does shift 24 Hornby Mk1 coaches without slipping. Which is about 8 more than the full size Duchesses managed.

[MacDuff999]

Interesting point you make about the drawbar DCB. I obtained some 5 and 6mm N/S strip to fashion new ones, possibly for my Wrenn 'Coronations', and my H/D bodied 'Duchess' on a Comet chassis. Haven't got round to changing any of them yet, partly as the H/D 'Duchess' will draw a slightly modified Wrenn tender, and the latter locos will need de-streamlined Comet tenders. 

[MacDuff999]

Unfortunately, modelling time has been a bit hard to come by this autumn, but some progress has been made - mainly on tenders. The Ivatt 'Coronation' tender for 'Sir William' etc. just needs the chassis to complete it now, and I am about three quarters the way to completing a Comet de-streamlined version for 46224  'Princess Alexandra' - of which I have attached a photo connected to the Wrenn loco which will assume that identity. I have replaced the original drawbar by another made from a 6mm strip of N/S, suitably measured and drilled to give a closer coupling. Very conveniently, it extends horizontally from the tender drawbar pivot point to that under the loco smokebox, passing through the original drawbar slot under the loco cab and the tender drawbar slot! Although the L/H side of the tender looks largely complete, I have yet to fit the tender front/coal plate, and th R/H tender side, as well as detailed fittings such as springs/axle boxes, turned buffers, coupling etc. The tender will be well coaled, thus allowing me to model the simpler version of the inner tender structure.

[MacDuff999]

Little modelling done over the last several weeks - Christmas/New Year, and either pouring rain or brass monkey temperatures down kin the garage workshop. Some detail fettling done, however, at the table, and am looking at the possibility of replacing handrails and maybe smoke deflectors on the Wrenn 'Coronation' bodies. Anyone know how long the boiler side handrail pillars are? They look quite long in photos, so would they equate to Gibson long or medium h/r knobs? The relevant LMS Loco Profile volume doesn't include these in the excellent drawings featured in the book.    

[MacDuff999]

Apropos a similar issue to that of 22nd. January post; how long were the 'Coronation' loco nameplates? From the LMS Loco Profile drawings, they look to be c. 6ft (24/5mm) in length. Anyone know for sure?  

[PaulaDoesTrains]

I've got "Historic Locomotive Drawing in 4mm Scale" by F.J.Roche. He doesn't give a dimension for the length of the Duchess nameplate but using dividers it's the same length on his drawing as the distance centre-to-centre of the middle and rear driving wheels which is stated at 7ft 3 inches. But for all I know the length may have varied depending on the name of the loco.

[92220]

I don’t know for sure but Sir William A. Stanier F.R.S. or City of Stoke-on-Trent probably has a longer nameplate than Queen Mary or Coronation?

 

Iain

[TerryD1471]

On 04/02/2022 at 21:12, MacDuff999 said:

Apropos a similar issue to that of 22nd. January post; how long were the 'Coronation' loco nameplates? From the LMS Loco Profile drawings, they look to be c. 6ft (24/5mm) in length. Anyone know for sure?  

Interesting question! I always thought that they were all positioned so that they started just after the 3rd boiler band and extended backwards over the 4th, but referring to my (too) extensive library, the majority seem to start ON the 3rd boiler band and typically extend back for about a quarter of their length beyond the 4th one. Short names like Queen Mary and City of Leeds still seem to be the same length, with larger gaps at the front and back of the names. Even Cities of Nottingham and Birmingham seem to fit into this "standard" length. HOWEVER when you get to names like Alexandra, Gloucester, Buccleuch and Sutherland, (i.e. more than about 18 letters/gaps) the plates are definitely longer and especially so (as per Iain) for Sir William and Stoke-on-Trent.

 

My guess would be that they are all centred on the same spot (about 2/3 of the way back between the 3rd & 4th boiler bands) and longer plates overlap forward & backward correspondingly. But it is a guess based on observation!

 

Hope this all makes sense.

[Wolf27]

Just came across this topic while browsing so I thought I would show my dads old Hornby Dublo Duchess from his childhood. We planned to fit a new chassis to it in the mid 80’s and detail it up a bit. This never really worked out so it sat in a box for a further 15 years when I decided to have another go. Only the body,  with new running plate details and splashers, and rear truck survived, this was fitted with a re wheeled Triang Sir Dinadin King Arthur Chassis with Airfix Royal Scot cylinders and Etched valve gear- possibly Southeast Finecast and etched smoke deflectors. Tender top is a plastic Hornby Dublo moulding on a Lima Crab underframe. The motor is a Mashima mounted in the tender, driving the loco via a drive shaft and flywheel. It’s a bit old looking now but I was pretty pleased with. It could do with some additional detailing around the front end, which I may do. Still never got the nameplates for it!

 

 

Edited February 14, 2022 by Wolf27
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[TerryD1471]

On 14/02/2022 at 22:11, Wolf27 said:

Just came across this topic while browsing so I thought I would show my dads old Hornby Dublo Duchess from his childhood. We planned to fit a new chassis to it in the mid 80’s and detail it up a bit. This never really worked out so it sat in a box for a further 15 years when I decided to have another go. Only the body,  with new running plate details and splashers, and rear truck survived, this was fitted with a re wheeled Triang Sir Dinadin King Arthur Chassis with Airfix Royal Scot cylinders and Etched valve gear- possibly Southeast Finecast and etched smoke deflectors. Tender top is a plastic Hornby Dublo moulding on a Lima Crab underframe. The motor is a Mashima mounted in the tender, driving the loco via a drive shaft and flywheel. It’s a bit old looking now but I was pretty pleased with. It could do with some additional detailing around the front end, which I may do. Still never got the nameplates for it!

 

 

Sounds exactly like the kind of modification I would do, but (Morecambe & Wise) not necessarily in that order!

 

It is a pity that the Hornby Dublo chassis was found wanting, since the original motor was prodigiously powerful, as long as it wasn't de-magnetised. The Mashima motor is fine, as indeed are the other aspects of the "rebuild", so I congratulate the builders on the work they've done.

[TerryD1471]

I've seen some interesting comments on this thread. One contributor made mention of the excessive gap between loco and tender, but to my mind that is of far less importance (and so easily corrected) than the following:-

1 The great lumpen forward part of the firebox just above the running plate which was designed to accommodate the huge H/D magnet pole pieces. This is so obvious that it has to be carved down as far as possible. There is quite a bit of scope for thinning it down to a (more) realistic profile, even if you are retaining the original H/D-Wrenn chassis-motor combination. If you are replacing the chassis, there is even more scope for correcting the firebox profile with drills, files and filler.

 

2 The trailing pony truck is pretty inaccurate, because the real loco had fixed frame extensions from just behind the coupled wheels up to the back end of the cab. The actual Bissell truck was quite a small item, pivoting in between these frame extensions.

 

3 The "skirt" between the base of the boiler and the footplate can be removed with drills and fine files. Quite laborious, but really worthwhile because it creates the illusion of a round boiler pretty well.

 

4 The cab windows are too small. These can be opened up with small files and the change is well worthwhile.

 

All of these points are illustrated on page 2 of this thread, so I would suggest that if my written word gets too tedious (yawn), the pictures are worth 1000 words!

 

Best wishes and happy filing/drilling!

 

Terry D

 

[MacDuff999]

Returned to the topic after a somewhat protracted absence; the weather here (S. Wales) has been and still is foul and very wet, and so little incentive to retire to the modelling table in the garage. Liked the look of your modified H/D loco Wolf - nice straight handrails and good-looking motion. I have, however, been doing a little with the DJH body and Comet smoke deflectors (recommended by Iain of the Motive Power for Camden thread), trying to get a nice straight handrail line from smokebox to firebox. Going back to nameplate length, P24 of the LMS Profiles book on the class shows the boiler clothing for non-streamlined locos with a nameplate approximately 6'3" long, its centre point just forward of the centre-line of the dome, and the front edge just over 4" forward of the 3rd boiler band. So it could be said a fair average length is c. 25mm., which seems a little short. I doubt the names for 46224 or 46256 would fit neatly into that length.  As with many aspects of achieving correct scale detail, I think good photographs will be the best guide, as long as you get a good view of the nameplate placement on the boiler clothing. 

[rodent279]

Reading this thread with interest, as I have an HD Duchess of Atholl. It's part way through a conversion to 2 rail that was started in about 1970 and never finished.

The body is not bad, paint work a little patchy but passable. The tender has still got non-insulated wheels, and has a dent in one side.

What is the impact on the value of respraying & detailing these things? Are they worth anything in original form?

[cypherman]

3 hours ago, rodent279 said:

Reading this thread with interest, as I have an HD Duchess of Atholl. It's part way through a conversion to 2 rail that was started in about 1970 and never finished.

The body is not bad, paint work a little patchy but passable. The tender has still got non-insulated wheels, and has a dent in one side.

What is the impact on the value of respraying & detailing these things? Are they worth anything in original form?

Hi Rodent,

Unless it is in mint condition and boxed about £30.00 to £50.00. Mint and boxed can fetch anything between £100.00 to £200.00. Some people have asked for more, But it is not worth what they are asking. Some people think because it is old it must be worth a lot or just chance trying to sell them at an inflated price.

[MacDuff999]

From recent experience, I would agree with Cypherman. Part of the problem is that the later Wrenn (pre-Hornby plastic-bodied) versions have one or two refinements the H/D ones do not eg turned safety valves inserted into the forward edge of a better-looking cab roof. The body moulding seems a bit sharper too. There is a Wrenn Connoisseur website which features 'Coronation' models in excellent condition, and at pretty mind-blowing prices too - some of them. But they are nice, and start at about £179.