Hornby A4 OO to P4 conversion

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60022Camden

Hornby A4 OO to P4 conversion

Postby 60022Camden » Fri Dec 25, 2020 5:53 am

Hi all,
I'd like to start out by wishing everyone a wonderfully happy Christmas! I'm brand new to this world of P4 and could use some help deciding how to go about conversions. I've been a OO guy for some time. I've not got a bunch of stuff so when I go to make a layout, I'd like to get it to the real thing as possible. I've got a Hornby "super" detail A4 (in my opinion a retool is overdue) and I've detailed it to the best standard I can without going straight through to EM or P4 gauge conversion. I've decided to go P4 because I'm a mad man on accuracy/true scale proportions. I've removed the valve gear on my Hornby A4 and replaced it with Bachmann A1 gear. It looks far more realistic and I'm quite pleased with the job. The only thing left to get this to look "right" is the P4 conversion. Since this is my very first conversion, are there any kits for conversion anyone would recommend? I'm very seriously looking into the brassmasters easichas conversion and detail kits for my model with the AG ultrascale wheels (and yes, I'm aware of how long it takes for the product turnaround). I'm also wondering if anyone has been clever enough to come up with a solution to the wrap-around cylinder valancing and actual cylinders themselves? The Hornby arrangement is quite an eyesore. I'm planning on modeling ECML in the summer of 1961 with both diesels and steam to give me a variety of locos to choose from. So far, the location hasn't been decided but I do have a list of locos in mind and a good number of named passenger services too. My idea is to have either a double or triple tracked mainline with a few signals, a signalbox, and possibly a branch line thrown in as well. So far I have four A4 locos on my list, an A3, a Peppercorn A1, and a class 40 as the mainline stars. I wanted to start with only engines for which I can obtain P4 gauge conversion components. All help and advice is well appreciated by this newcomer!
Best,
Camden
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Steve Carter
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Re: Hornby A4 OO to P4 conversion

Postby Steve Carter » Sat Dec 26, 2020 2:31 pm

Hi Camden and welcome to the Society.
Did you get my welcome email?
I will be posting your New Member Pack once the Post Office reopens after the Christmas break.

Glad to see you making use of thevforum already :thumb

I'm not an LNER modeller but I do admire the A4's, there's just something majestic and powerful about them.
I am certain you will get some replies from others who can answer your questions. The brassmasters chassis may be the way to go but it would be sensible to check with them that the Hornby variant of A4 you have is suitable for their Easichas and also to confirm what size axles are needed their chassis in P4. sales@brassmasters.co.uk
They are very helpful

God luck

Steve
Steve Carter

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Paul Willis
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Re: Hornby A4 OO to P4 conversion

Postby Paul Willis » Sat Dec 26, 2020 5:59 pm

Hi Camden,

Welcome to the Society, and the Forum. You've already found the best place to begin - "Starting in P4".

I haven't tried one of the Easichas kits myself, but the newly released J15 one is the first that fits my interests. So I'll probably be giving it a try in the near future. However, they are well spoken of, and there is certainly a comprehensive set of notes and photos on the Brassmasters website to advise you.

The detailed model that you have already looks the part. All the best with the build.

Cheers
Paul
Beware of Trains - occasional modelling in progress!
www.5522models.co.uk

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PeteT
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Re: Hornby A4 OO to P4 conversion

Postby PeteT » Sat Dec 26, 2020 6:41 pm

Hi Camden,

I've done a 3F Easi-chas, and an A3 underway - and while the instructions are based on 'no soldering', it does help to do a bit (certainly for the likes of pickups!).

I've done both of mine with Ultrascale wheels, and on ordering there is a text box where you can note that it is for an Easi-chas and the right diameter axles will be provided. Alan Gibson do the right wheels as well, though I haven't used them in these conversions.

I think the basic easi chas concept works very well - just make sure there isn't too much vertical play in the driven axle or the gears could come out of mesh.

I like what you've done with the A4! I also think the A4 or A3 would be a good starting point, then with the A1 you can decide whether to continue that method or go for a Dave Bradwell chassis for it. Both options work, but it is a question of time/cost vs end result.

There are also options to build an easi chas with a replacement gearbox (such as those from high level kits) - I'd suggested building the first as per the instructions and it will work perfectly well. There is a build of the Brassmasters/Bachmann Ivatt 4 Mucky Duck covered in MRJ which replaces the gearbox.

Cheers,
Pete

60022Camden

Re: Hornby A4 OO to P4 conversion

Postby 60022Camden » Sun Dec 27, 2020 3:54 am

Thank you all very much for the advice! I am looking at ordering another A4 and doing one conversion first as a "test" so to speak to see how difficult the process is. I've never undertaken anything quite like converting engines to run on different gauges of track before. I'm well-acquainted with plastic work but have never done any major metalwork before. This will be my very first go. A friend and I are working on the Hornby Gresley pacific tender insets. The water filler area and coal bunker are missing loads of rivets, supports, bracings, and ribbing inside and we are attempting to rectify the issue via custom 3D printed inserts to replace the stock Hornby ones. I've got a resin 3D printer so it seemed the most logical option to make computer drawings and to have them 3D printed. I'd looked into the instructions for the brassmasters easichas kit and it called for 3mm axles. I've debated using the ultrascale wheels because of their wait time... but I decided it was worth it to get quality wheels with nickel tyres, a highly corrosive-resistant metal. I'll be renaming/renumbering this coming A4 to 60022 'Mallard'... my favorite steam loco ;)

Steve... I did receive your welcome email. It was very much appreciated!

Mark Forrest
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Re: Hornby A4 OO to P4 conversion

Postby Mark Forrest » Sun Dec 27, 2020 9:37 am

Welcome to the Society and the Forum, Camden; that A4 looks very nice.

Although I've modelled diesels in both P4 and EM for a good few years, l'm a relative newbie when it comes to modelling steam locos. My approach has been to start off with inside cylinder 0-6-0s to get something up and running before progressing to more complicated prototypes. I'm finding this useful as I'm building up skills and confidence as I go along.

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PeteT
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Re: Hornby A4 OO to P4 conversion

Postby PeteT » Sun Dec 27, 2020 11:00 am

Mark Forrest wrote:My approach has been to start off with inside cylinder 0-6-0s to get something up and running before progressing to more complicated prototypes.


I thought about mentioning this Mark, but decided against on two counts. Firstly the easi chas reuses the original valvegear, so the complication of assembling it is lost - and the complication of return cranks has already been dealt with by Camden in grafting the Bachmann valvegear onto his current A4.

That said, I agree it also removes potential problems such as clearance, and fewer potential derailment opportunities if bogie and pony/Cartazzi's are out of the equation.

I think Ultrascale do a drop in set for the class 40 (though Penrith sprung bogies would also be worth looking at to see if they are to your taste). I've lost track with where Accurascale have got to with their Deltic which would be another 'quick access' route if it is imminent.

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Will L
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Re: Hornby A4 OO to P4 conversion

Postby Will L » Sun Dec 27, 2020 12:23 pm

60022Camden wrote:Hi all,
I'd like to start out by wishing everyone a wonderfully happy Christmas! I'm brand new to this world of P4 and could use some help deciding how to go about conversions.


Hi Camden, good to see you on here and getting stuck in. One of the great things about the society is this forum. There always seems to be somebody out there who will be only too happy to answer, or give an educated opinion on, almost any (model railway) question. The nature of the society is that it does attract people who actually like building stuff, so it looks like you will fit in rather well. The key requirement for being a good modeller is persistents, if at first you don't get it right keep at it till you do, you will learn any skills you don't currently possess fast enough.

I've got a resin 3D printer so it seemed the most logical option to make computer drawings and to have them 3D printed. I'd looked into the instructions for the brassmasters easichas kit and it called for 3mm axles. I've debated using the ultrascale wheels because of their wait time... but I decided it was worth it to get quality wheels with nickel tyres, a highly corrosive-resistant metal.

IInteresting that you acquired a 3D printer so early in a modelling career, which is a real sign of how things are changing, and to what extent modelling these days is becoming as dependent on CAD skills as on metal bashing. That said don't be put off acquiring the metal bashing skills as well, because, in the end metal is still the preferable modelling material for many jobs.
I've debated using the ultrascale wheels because of their wait time... but I decided it was worth it to get quality wheels with nickel tyres, a highly corrosive-resistant metal.


And don't be put off Gibson wheels just because Ultrascale are arguably of higher quality. They also cost a lot more, take a long time to come and have a more limited range. Many of us get fine service from Gibson wheels. Steel tires are really not an issue. Steal rail can be, depending on where you want to keep the layout, but I can’t think of anybody who takes any sort of care of his stock who has problems with rusty tires! The real issue with Gibson wheels is that they really need to be fitted to the axle once only, it’s when you start removing and refitting them things start to go wrong.

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Noel
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Re: Hornby A4 OO to P4 conversion

Postby Noel » Sun Dec 27, 2020 3:26 pm

Will L wrote:in the end metal is still the preferable modelling material for many jobs.


This may already no longer be true. Much depends on what period you choose to model. As a BR modeller, I normally use plastic, either kits or r-t-r. Locomotives can be rewheeled r-t-r, which has much more reliable outcomes than was possible in the past. I'm happy to use brass wagon chassis if convenient for producing a particular outcome [rare, mostly for tank wagons with their open frames], and have couple of EasiChas to address in the future, but that is about it. The availability of 3D printing and its rapid evolution and the advent of remotely controllable battery driven locos [the evolution of both of which can be expected to continue, I think] has resulted in a paradigm shift in what can be done to meet individual modeller's desires; those who are so wedded to etched brass may soon be dinosaurs...
Regards
Noel

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Will L
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Re: Hornby A4 OO to P4 conversion

Postby Will L » Sun Dec 27, 2020 5:34 pm

Noel wrote:
Will L wrote:in the end metal is still the preferable modelling material for many jobs.


This may already no longer be true. Much depends on what period you choose to model. As a BR modeller, I normally use plastic, either kits or r-t-r. Locomotives can be rewheeled r-t-r, which has much more reliable outcomes than was possible in the past. I'm happy to use brass wagon chassis if convenient for producing a particular outcome [rare, mostly for tank wagons with their open frames], and have couple of EasiChas to address in the future, but that is about it. The availability of 3D printing and its rapid evolution and the advent of remotely controllable battery driven locos [the evolution of both of which can be expected to continue, I think] has resulted in a paradigm shift in what can be done to meet individual modeller's desires; those who are so wedded to etched brass may soon be dinosaurs...

Oh I don't know, as we develop new methods we don't often discard the old ones entirely. The only material/technique I can think of quickly which seems to have disappeared completely in my time is the use of shellac to reinforce card, and card itself is still a much-used material for buildings and the like. While I'm sure 3D prints will gain an increasing hold in some areas, etched brass is such a useful material, and as CAD skills become more common, much more accessible to the average modeller, I think it will be with us for a long time yet. Also anybody who wants to do the sort of things I do to loco chassis is going to be hard put to find anything better at the moment. Sintered metal 3D prints possibly but I don't think that's a hobby level technology yet.

Anyway, I rather doubt the RTR market is ever going to intrude into my world much, and I suspect I'm not the only one. The J15 might possibly do it, but I don't like the way they have fudged the handrails and I have at least one perfectly good brass one that still needs building. That is once the buckjumpers, and the F6 I haven't talked about much yet are done.

Also don’t no longer available metal kits go for silly prices on Ebay. Must be a bit of a demand out there somewhere.

60022Camden

Re: Hornby A4 OO to P4 conversion

Postby 60022Camden » Sun Dec 27, 2020 10:04 pm

On the topic of metalwork vs. plastic work... Metal will, in my opinion, always trump over plastic. Metal is far more rigid and robust and is not susceptible to warping, unlike plastic and resin 3D prints. However... CAD drawings are the easiest way to get things to look accurate. Laser-engraving and etching is not something we can easily do ourselves... yet. I'm sure the time when we can do these things ourselves is not far away.

I took a look at the J15. Gorgeous model! The wire pickups had me a bit weary. I don't know that I'd be able to do as good a job on that. The A4 still uses the tender pickups and transferring the pickups from the loco to the top of the chassis wouldn't be difficult if insulated properly. I just ordered the A4 I was thinking about purchasing. It is Hornby's R2535 'Woodcock' 60029 which will be renamed and renumbered to 60022 'Mallard' with red nameplates and warning flashers as she appeared in the summer of 1961.

I had a look at the brassmasters A4 easichas kits a while back before I got serious about doing the conversions. The kit will work on both of my existing A4 locos. First things first tho, rename/renumber, valve gear transplant, and DCC sound fit 'Mallard'. I've got the chip but need a double sugar cube speaker in the engine. 'Silver Fox' is already sound fitted.

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45609
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Re: Hornby A4 OO to P4 conversion

Postby 45609 » Mon Dec 28, 2020 12:31 pm

The question was raised in the original post about how to deal with the slab sided cylinder clothing on the Hornby model. The pictures below show a model I built in OO gauge a few years ago using the Hornby body as a basis. The chassis is Comet and as part of the chassis construction I built up the lower cylinder halves from plasticard and then profiled them to represent the turn under. When the chassis is parted from the body the lower halves of the cylinders go with it.

60012_RHS.png


60012_LHS.png


The disadvantage of this approach is the horizontal join line at piston rod height. It requires a very careful cut of the Hornby body to get a close fitting join. Even then it is still visible but does look better than the flat sided alternative. Especially from normal viewing distances and when racing past on the Elizabethan.

Cylinder CU.png


Accomplishing something similar on the Hornby chassis in conjunction with the Brassmasters Easi-chassis might require differences in the detailed execution but is probably possible.

Cheers...Morgan
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60022Camden

Re: Hornby A4 OO to P4 conversion

Postby 60022Camden » Mon Dec 28, 2020 4:22 pm

45609 wrote:The question was raised in the original post about how to deal with the slab sided cylinder clothing on the Hornby model. The pictures below show a model I built in OO gauge a few years ago using the Hornby body as a basis. The chassis is Comet and as part of the chassis construction I built up the lower cylinder halves from plasticard and then profiled them to represent the turn under. When the chassis is parted from the body the lower halves of the cylinders go with it.

60012_RHS.png

60012_LHS.png

The disadvantage of this approach is the horizontal join line at piston rod height. It requires a very careful cut of the Hornby body to get a close fitting join. Even then it is still visible but does look better than the flat sided alternative. Especially from normal viewing distances and when racing past on the Elizabethan.

Cylinder CU.png

Accomplishing something similar on the Hornby chassis in conjunction with the Brassmasters Easi-chassis might require differences in the detailed execution but is probably possible.

Cheers...Morgan


Morgan,
This looks 1000 miles better than what Hornby has foolishly decided looks appropriate. I also really like the eccentric gear on this chassis. It's got the correct two small slots on the expansion link. Methinks it actually may be possible to CAD design wider cylinders that have the correct bottom curvature and to avoid the seam with still being able to remove the body easily. I'd thought about designing these cylinders to split across the vertical plane instead of the horizontal plane to be able to avoid the seam line on the side and move it to the underside of the loco where you only see it if you turn it over. Whether or not I'll tackle this is in the air but I do have a spare Hornby chassis and body I could try this method out on. The idea would be to remove part of the Hornby cylinder valancing as you've done and install the outer part of the cylinder to the body, fill the seam line, repaint that affected area, and then you'd have the issue resolved.

Daddyman
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Re: Hornby A4 OO to P4 conversion

Postby Daddyman » Wed Dec 30, 2020 8:25 am

This is the solution I went for a few years ago - just a question of thinning down the plastic on the inside enough so that it will bend (perhaps with the help of liquid poly). Head-on photo shows one side done and one side not for contrast. The much harder job is sorting that b. awful joint at the front!

I never went any further on this loco as I went off plastic locos at about the same time I went off big locos. But I think the plan was to somehow move the front of the cylinder forwards, so that the circular cover is in the right place relative to the valance (as on Morgan's).

20180704_200011.jpg


20180704_200130.jpg
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60022Camden

Re: Hornby A4 OO to P4 conversion

Postby 60022Camden » Thu Dec 31, 2020 1:06 am

Daddyman wrote:This is the solution I went for a few years ago - just a question of thinning down the plastic on the inside enough so that it will bend (perhaps with the help of liquid poly). Head-on photo shows one side done and one side not for contrast. The much harder job is sorting that b. awful joint at the front!

I never went any further on this loco as I went off plastic locos at about the same time I went off big locos. But I think the plan was to somehow move the front of the cylinder forwards, so that the circular cover is in the right place relative to the valance (as on Morgan's).

20180704_200011.jpg

20180704_200130.jpg

This is a rather interesting approach I hadn't necessarily considered... Shave off the inside, make new cylinders and shape the existing valances around them. I must say, an overwhelmingly clever approach. I'd personally have a go at shaving them right thin and heating the plastic with a hairdryer to bend the shape right round the cylinders and form a piece of brass and epoxy it in place behind the work to give it a rigid frame to avoid any warping or misforming which will most certainly happen over time. Definitely some fuel for thought!

Daddyman
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Re: Hornby A4 OO to P4 conversion

Postby Daddyman » Thu Dec 31, 2020 8:20 am

60022Camden wrote: This is a rather interesting approach I hadn't necessarily considered... Shave off the inside, make new cylinders and shape the existing valances around them. I must say, an overwhelmingly clever approach. I'd personally have a go at shaving them right thin and heating the plastic with a hairdryer to bend the shape right round the cylinders and form a piece of brass and epoxy it in place behind the work to give it a rigid frame to avoid any warping or misforming which will most certainly happen over time. Definitely some fuel for thought!


I'd be careful with the hairdryer. I had a few knackered bodies to practise on (though I only needed one). I found that the plastic was starting to crack if I tried to bend it any further - though things might have been better if I'd used heat. You have to be very careful (as with all things) to get the bend even - otherwise, it will show when the light is on it. Perhaps some sort of a wooden former could be rigged up, and then the heat applied?

I did consider the brass backing and epoxy approach, but you have to remember that this part of the model needs to be able to flex so that you can get the body off. I suspect in flexing it repeatedly (or even once) you might tear the plastic away from the metal.

Terry Bendall
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Re: Hornby A4 OO to P4 conversion

Postby Terry Bendall » Thu Dec 31, 2020 2:01 pm

Daddyman wrote:I'd be careful with the hairdryer.


This can be done, but some care is needed. There are two main types of plastics - thermoplastics that can be heated and shaped many times, and thermosetting plastics that can only be heated and formed once. The type of plastic used for electrical fittings are an example of thermosetting plastics, Most other plastics, in common use, including those used to make models, are thermoplastics.

As an alternative to a hair dryer a heat gun of the sort used for burning off old paint can be used but on a low setting. It is an advantage to confine the heat and some heat guns have a conical shaped nozzle that will do this. If a hair dryer is used fashioning a nozzle from a "tin" can would be an advantage. I would tend to experiment on an old body first.

Terry Bendall

60022Camden

Re: Hornby A4 OO to P4 conversion

Postby 60022Camden » Sat Jan 02, 2021 4:12 pm

I'd thought of the plastic melting elsewhere... I've got a spare body to try this out on so I'll have to try it out sometime soon on that.


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