Up-grading Hornby-Dublo/Wrenn 'Duchesses'

[TerryD1471]

I thought that I had better "put my money where my mouth was" so to speak, as the topic is about H/D or Wrenn Duchesses which are modified. 

This is a H/D City of London still with the H/D trailing truck in situ and later:-

The same loco now in primer and with a replacement trailing truck courtesy of Comet.

Points to note are (1) the tender has been replaced by a Ks white metal one, still awaiting the ladder over the back and some front footsteps. (2) The front of the firebox has been carved away as much as I dare to try and replicate the sloping throatplate (see the DJH model for comparison). (3) The skirt at the bottom of the boiler has been opened out using drills and files to make the boiler look round; there's still a bit to do there! (4) Cab windows have been opened out, (5) 26mm Romford wheels have been fitted; they JUST fit in beneath the magnets of the huge motor.

The haulage capacity is tremendous; it hardly notices 15 kit-built coaches and this is partly due to the neodymium magnets with which it has been remagnetized.

Another Duchess, a Wrenn one this time, which has had the same treatment, but which is towing a carved up H/D tender to represent more accurately a destreamlined (Type 1) tender. The valve gear has had some alterations to make the motion more realistic.

The third one is also a H/D body shell carved up to represent 46257 City of Salford. Still awaiting plates and final paint touches, this one has a scratch brass chassis with 26 mm Romford drivers, a D13 motor driving through 40:1 gears and Comet valve gear and motion. Not quite as powerful as the H/D chassised ones, but the firebox can be shaped to represent the sloping throatplate more accurately, because I'm not trying to cope with the enormous motor of the original H/D design.

 

I hope this illustrates the mods needed.

Edited August 24, 2021 by TerryD1471

[97xx]

I have a rather tired City of London I am considering tidying up.

 

What have people done to correct the ride height when going to 26mm drivers from the HD 22mm?

[TerryD1471]

2 hours ago, 97xx said:

I have a rather tired City of London I am considering tidying up.

 

What have people done to correct the ride height when going to 26mm drivers from the HD 22mm?

Bear in mind that with the smaller wheels, the ride height was probably a little low anyway and that the increase of 4 mm in wheel diameter only results in a 2 mm increase in ride height, I have decided to accept that the ride height is acceptable. It may be a millimetre too high, but that only enhances the gravitas of the loco for me! It seems to me to go with the ride height of the tender, so I suggest you look at the pictures and judge for yourself whether you find the overall stance of the loco(s) acceptable.

 

 

[farren]

A interesting topic sorry I missed it till now. I recently had my hands on my first Hornby Double 0 Coronation which a friend asked my to re-livery. And well doing I did wonder if it could be brought up to date.

Just wondering how easy is the metal body to work on. 

[TerryD1471]

12 hours ago, farren said:

A interesting topic sorry I missed it till now. I recently had my hands on my first Hornby Double 0 Coronation which a friend asked my to re-livery. And well doing I did wonder if it could be brought up to date.

Just wondering how easy is the metal body to work on. 

The body is cast mazak and as previous contributors have noted, does not solder. However superglue &/or araldite is fine. The principal area for attention is the forward lower part of the firebox which is too fat, to allow clearance round the motor magnet pole pieces. It can be slimmed down using files &/or dental burrs in a mini electric drill, but don't go too far or you'll go through the metal! See the previous pictures. Also to create the illusion of a round boiler, the skirt where the boiler and the footplate join can be drilled through and filed to shape to allow "daylight" through.

[MacDuff999]

Well yes, perhaps a kit would be a better option Cypherman, saving some time and a fair amount of fettling. As I am sure we all realise though, there is a trade-off between time and cost; especially as a DJH kit, new, is now north of £200, without wheels etc. In the end, it all comes down to the level of accuracy you want - and can afford - in your models. The points you make Terry, are I think well-made, but at this stage at least, I can live with the HD/Wrenn models with just a few easier and quicker changes. I may have mentioned I have already replaced the bogie wheels on 'City of London' (soon to become 'Carlisle'), and I will find a way to neatly attach a pair of screw couplings. I have also noticed that the slot in the rear outer frame extensions over the pony truck are marked but filled in, so I am going to carefully try and open them out, so they look more like the real thing. The loco will also really need a Comet de-streamlined tender, as the ones made and attached by H/D are from the 8F, and are rivetted, so certainly not right. I am looking at using 6'6" 'Princess Royal' wheels Terry, having obtained a 27mm set for the DJH loco, and they look decidedly tight. Not ordered them from Markits yet though. The body of the DJH loco, incidentally, was already quite nicely assembled when I acquired it, so I am reluctant to start making any significant changes to it. 

 

Ian.     

[TerryD1471]

Thanks Ian, I understand where you're coming from; if it's any criterion, I still have a Wrenn City of Birmingham bought new in 1978(ish) and all that has been done to that is a set of Romford 26 mm drivers and bogie wheels. The rest is still "as is" and it still works its turns on Hest Bank.

 

I was a bit perplexed by your comments about the tender of City of London; the 8F tender body is cast mazak and riveted whereas the pacifics all had plastic bodies with flush sides. The tender underframes were the only common parts.

 

As an aside, I still think there's a certain irony in the fact that the best kits (DJH), if built as they are, still don't produce as well proportioned a model as the current Hornby RTR Duchesses (or indeed the old H/D bodyshells)

 

ATB

 

Terry

 

 

Edited August 31, 2021 by TerryD1471

[MacDuff999]

My mistake about tenders Terry; I hadn't looked closely enough when I got the loco, as I was more focused on the loco itself. Or I need new glasses! I have drilled through the outer frame extension slots now, but they will look somewhat better when the loco is weathered. I am curious how you fixed the Comet rear frame extensions to the H/D loco; it looks as though you fitted a Comet pony truck as well. I will probably be ordering the 'Princess' drivers for the H/D/Comet 'Duchess' later this week, so I should be able to post a photo of the fully-wheeled chassis under the H/D body, to give a better idea how it will look together. How well or otherwise does the H/D loco look against a Comet tender on its original wheels? Is there quite a discrepancy in heights? I am a bit cautious about changing the drivers to more scale diameter ones, and what might be involved regarding any changes to the valve gear. 

[Sandhole]

51 minutes ago, MacDuff999 said:

My mistake about tenders Terry; I hadn't looked closely enough when I got the loco, as I was more focused on the loco itself. Or I need new glasses! I have drilled through the outer frame extension slots now, but they will look somewhat better when the loco is weathered. I am curious how you fixed the Comet rear frame extensions to the H/D loco; it looks as though you fitted a Comet pony truck as well. I will probably be ordering the 'Princess' drivers for the H/D/Comet 'Duchess' later this week, so I should be able to post a photo of the fully-wheeled chassis under the H/D body, to give a better idea how it will look together. How well or otherwise does the H/D loco look against a Comet tender on its original wheels? Is there quite a discrepancy in heights? I am a bit cautious about changing the drivers to more scale diameter ones, and what might be involved regarding any changes to the valve gear. 

I have a Hornby Dublo Duchess fitted with 26mm wheels.
There were no changes needed to the valve gear.
Chris.

[MacDuff999]

What kind of wheels are fitted Chris, are they Markits/Gibsons for example? In which case, do they work with the H/D crankpins. so you don't have to change the rods etc? 

 

Ian.  

[Sandhole]

3 hours ago, MacDuff999 said:

What kind of wheels are fitted Chris, are they Markits/Gibsons for example? In which case, do they work with the H/D crankpins. so you don't have to change the rods etc? 

 

Ian.  

They are old school Romfords.
Brian Wiltshire, the guy who did the fitting for me used the origional rods on Romford pins.
He bonded washers to the rods to enable them to be fitted.
Chris.

[melmerby]

On 21/08/2021 at 16:47, MacDuff999 said:

Terry, or anyone, have you ever replaced the flangeless centre driver on a H/D model?

Yes

I had (still have albeit very messed around) Castle with near scale Romfords all round with flanges, insulated both sides and pickups on all.

I had also bored out the axle holes and put brass bushes in.

Another mod was fitting a Mashima totally inside the boiler and a backhead & floor in the cab, instead of the ringfield motor.

It is an as yet unfinished back-burner project

Still keeps most of the HD chassis with it's wrong wheelbase.

Edited September 1, 2021 by melmerby

[TerryD1471]

On 31/08/2021 at 17:44, MacDuff999 said:

My mistake about tenders Terry; I hadn't looked closely enough when I got the loco, as I was more focused on the loco itself. Or I need new glasses! I have drilled through the outer frame extension slots now, but they will look somewhat better when the loco is weathered. I am curious how you fixed the Comet rear frame extensions to the H/D loco; it looks as though you fitted a Comet pony truck as well. I will probably be ordering the 'Princess' drivers for the H/D/Comet 'Duchess' later this week, so I should be able to post a photo of the fully-wheeled chassis under the H/D body, to give a better idea how it will look together. How well or otherwise does the H/D loco look against a Comet tender on its original wheels? Is there quite a discrepancy in heights? I am a bit cautious about changing the drivers to more scale diameter ones, and what might be involved regarding any changes to the valve gear. 

Hi Ian

 

I have taken some pictures of the various locos I have mucked about with, but sadly technology has got the better of me! I will however persevere and try and get pictures to you.

You are quite right about your concerns about ride height, but I have checked the several Duchess locos that I have messed with and the following issues come to mind:-

1 Checking a H/D Duchess (26 mm drivers) against a Comet tender, there is a slight (<1 mm) difference in height, but that same difference is there with the K's loco that is supposed to tow the tender!

 

2 Sandhole raises the question of whether it's necessary to alter the valve gear. I have done so as the standard configuration of H/D & Wrenn models is in full forward gear. That's the trouble with Walschaerts valve gear; the valve rod moves up and down on the eccentric link according to whether it's in forward, mid-gear or backwards. It is very difficult to model, so if you fix the valve rod, at some point you've almost always got it wrong! (Several of my pacifics have not been altered.)

What I did was to unpick the valve rod attached to the eccentric link and fix it instead at the top, so it appears to be in mid-gear. That is the way many proprietary models are set up nowadays, so "you pays yer money and makes yer choice!"

 

3 You asked about the pony truck; it is a Comet truck, but I had to make a brass bracket to solder to it to allow it to be screwed into the H/D chassis. The Comet frame extensions are soldered to a brass angle underneath the back of the cab floor and that also allows a towing loop to be attached for the tender to hook up to.

 

If only my photos could be attached!

 

Edited September 2, 2021 by TerryD1471

[TerryD1471]

I have at last managed to conquer my tech inadequacies, and attach some pictures to illustrate my comments above.

For Ian, this shows how the Comet frame extensions and pony truck have been constructed; a small brass bracket has been soldered onto the Comet truck assembly and the fixing screw passes through this.

The question was raised about the valve gear on the Wrenn/H/D locos. This unaltered gear is on my old City of Birmingham. It shows how the valve rod is attached half way down the "eccentric link". This gives the impression of a loco in full forward gear, a position it would only be in when starting.

Here we see how the valve rod has now been re-positioned attached to the top pivot of the "eccentric link."This gives the impression of a loco in mid gear which is close to the position it's in when running fast. It also gives a less exaggerated movement to the combination link, since the valve spindle moves rather less.

On to a rather dark picture of a very old H/D Duchess with a scratch brass chassis but retaining the original cylinders and motion. Here again the position of the valve rod has not been altered but is still pivoted at the middle of the "eccentric link". The motion of the valve gear tends to be more exaggerated  on this loco too.

 

On to the issue of tender heights.

 

Here we have one of the later H/D/Wrenn Duchesses which has been temporarily paired with the Type 3 tender intended for City of Hereford. If the locomotive does sit a little high, it can't be very much. Also this view is helpful because the rear pony arrangement is more visible.

 

And here is City of Hereford as far as she has got. This is slightly off topic because she is a Ks body kit atop a brass chassis, and not a H/D Duchess, but it makes an interesting comparison. I like the Ks kit, although I have to say the splashers look a bit beefy! I still think that the overall effect is that she is a bit better proportioned than the DJH locos as built. She has been temporarily paired with her original tender which will eventually be put behind and H/D Duchess when her correct Type 3 tender has been finished.

 

Speaking of DJH locos:-

 

This is City of London, built about 15 years ago from a DJH kit. They are lovely to build, being a super composite kit of white metal and etched brass parts. However, they needed quite a bit of fettling, notably because the cab roof needed adjusting downwards and the firebox/boiler joint is tricky. However it was not until she was finished and painted that I realised (a) that the smokebox was too long and (b) the footplate around the inside cylinders was too short. This latter I have attempted to rectify by inserting a piece of 1.6 mm brass bar in between the footplate and the buffer beam. The picture shows how this has been done before fettling and painting.

 

Once again, to finish off, we have a H/D loco correctly paired with a Type 2 (ex-streamline) tender, which she will eventually tow.

 

This too, has had the valve gear altered as above. She will, when finished, be 46248 City of Leeds, one of Crewe North's finest.

 

Edited September 2, 2021 by TerryD1471

[MacDuff999]

Thanks very much gents for the information and comments (and the photos Terry), which will help me progress the 3 models I have to work on.  I have solved one tender issue though. As I recently acquired a rather nice Wrenn 'City of Birmingham', I realised that its tender would be the correct type to go with my H/D body, Comet chassis ' Duchess of Montrose' to be, with a little tweaking. I will then need only 2 Comet de-streamlined tenders for 46224 and 46238. I found out yesterday, that Titfield Thunderbolt Bookshop has 1 copy of the LMS Loco Profiles Photographic Supplement in stock. I will likely send for that to supplement my prototype images resource, to make sure I get as much detail right as possible on the models. 

 

Ian.     

[TerryD1471]

On 03/09/2021 at 12:31, MacDuff999 said:

Thanks very much gents for the information and comments (and the photos Terry), which will help me progress the 3 models I have to work on.  I have solved one tender issue though. As I recently acquired a rather nice Wrenn 'City of Birmingham', I realised that its tender would be the correct type to go with my H/D body, Comet chassis ' Duchess of Montrose' to be, with a little tweaking. I will then need only 2 Comet de-streamlined tenders for 46224 and 46238. I found out yesterday, that Titfield Thunderbolt Bookshop has 1 copy of the LMS Loco Profiles Photographic Supplement in stock. I will likely send for that to supplement my prototype images resource, to make sure I get as much detail right as possible on the models. 

 

Ian.     

Hi Ian

 

You are almost correct when you say that the tender is correct for the type 2. The only error with the H/D/Wrenn type plastic bodied tender is that it has a high front cut out, like the Type 1. However, I have rectified this (sort of!) by carving away the high front until it now resembles a low front cut out. If you look at the various tender types, you will see the difference I am referring to. Happy carving!

 

Terry

[MacDuff999]

Well, Sod's Law strikes again!  Although the thought had occurred to me Terry; I just hadn't checked it with the LMS Profiles book. I will see how successful (or otherwise) I am in excising the unwanted protrusions behind and below the buffer beam, so that I might be able to attach a better brass strip buffer beam, drilled etc. for turned buffers and scale screw coupling. If that goes pear-shaped, it's a Comet replacement I think. Meanwhile, I now have a half-built tender body for the DJH Ivatt 'Sir William' etc.  Slow, but still progress.

 

Ian. 

[MacDuff999]

More progress on the DJH tender, but also some work done on the green one off 'City of Birmingham'. The ugly lugs below the rear buffer beam (ex-tension lock coupling) and the cast buffers have been removed, and it looks better already. Some N/S strip from a certain emporium will form a rather improved buffer beam, fitted with turned buffers and a screw coupling. 'Princess Royal' driving wheels, to give a little more clearance I hope, are in the post, and on delivery will be fitted to the Comet chassis temporarily placed under the H/D 'Duchess' body. Anyone know how long 'Coronation' nameplates were? Or does it depend on the length of the name? I am just wondering if I will need to try and file down (or extend) part of the nameplate 'hump' on the cast body.

 

Ian. 

[TerryD1471]

2 hours ago, MacDuff999 said:

More progress on the DJH tender, but also some work done on the green one off 'City of Birmingham'. The ugly lugs below the rear buffer beam (ex-tension lock coupling) and the cast buffers have been removed, and it looks better already. Some N/S strip from a certain emporium will form a rather improved buffer beam, fitted with turned buffers and a screw coupling. 'Princess Royal' driving wheels, to give a little more clearance I hope, are in the post, and on delivery will be fitted to the Comet chassis temporarily placed under the H/D 'Duchess' body. Anyone know how long 'Coronation' nameplates were? Or does it depend on the length of the name? I am just wondering if I will need to try and file down (or extend) part of the nameplate 'hump' on the cast body.

 

Ian. 

Yes, Ian, the nameplates were shorter than on certain RTR Duchesses and in most (if not all) cases the nameplates started or finished behind the 3rd lining boiler band, which means there is some carving to do. There are manufacturers of nameplates who offer "replacement" or scale name plates and the latter are appreciably smaller than the former. I confess I have used both types, but then that just shows how undiscriminating I am. As always, a good look at photos is the best guide.

[MacDuff999]

I have a couple of nameplates already for the locos I am working on. What I should really do, of course, is measure the things and compare with the support plate on the loco boilers! The LMS profile book drawings seem to give measurements, but are slightly confusing; I still think it depends on the length of the loco's name. 

 

Ian.

[TerryD1471]

On 01/09/2021 at 11:02, MacDuff999 said:

What kind of wheels are fitted Chris, are they Markits/Gibsons for example? In which case, do they work with the H/D crankpins. so you don't have to change the rods etc? 

 

Ian.  

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.

[MacDuff999]

Been working on the DJH tender lately, and thought I would finish it soon. Foolish boy! Last stage (almost) was addition of steps - etched at front and W/M at rear. I had problems in attempting to attach these, and was really quite unimpressed with the design of the main chassis block and the cast frame/axle-box/springs, which provided little in the way of support for the steps to help with the soldering process. I ended up binning the idea of completing the tender as intended, and have sent for the appropriate Comet chassis kit. With its all-brass parts and a rather better design, it should go together more easily, and once assembled, provide a suitable base for the DJH tender body - which went together fine. I now also have the N/S strip with which to fashion a better buffer beam for the Wrenn 'Duchess' tender. Will post a photo or two when there is something worthwhile to see.  

 

 

[MacDuff999]

No further work on tenders at the moment, as I have been progressing the Comet chassis for the H/D 'Duchess' up-grade. I took forum members' advice, and purchased a pair of Markits machined crosshead/piston rod parts; they are certainly more superior to those provided in the Comet chassis kit, and the cylinder liner sleeves which come with them, make for silky smooth operation when tried out prior to full assembly, which is the next job.   

 

 

[MacDuff999]

Am getting dangerously close to the layout wiring stage, and my knowledge of such things is pretty basic. A modelling colleague has said there are some useful items on the 'net to assist the electrical novice. Any ideas what and where gents? 

[cypherman]

Hi Macduff,

Best place I can think of is You Tube. Like this one,

 

Edited October 13, 2021 by cypherman