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Re: 2002's 4mm projects - various A4s (de-valencing) etc

Posted: Wed Mar 21, 2012 9:45 am
by Saint Johnstoun
4-8-2

My original tender drive 4-8-2 used 2 old old Margate Tender Drive A1 bodies and the cab from an A4. My current project is using two current China A3 bodies and a Bachmann A4 cab.


Somewhere in the dark and distant past there are piccies of my original conversion on this site.

Re: 2002's 4mm projects - various A4s (de-valencing) etc

Posted: Wed Mar 21, 2012 10:40 am
by Atlantic 3279
Given the virtual non-availability (as far as I can find) of the new China-made super-detail A3 bodies, the high prices that they can command when they rarely appear, and the "fragility" which is objected to in a previous post, I would strongly suggest that it is worth looking at the option of two, cheap, Margate Hornby round-dome (A1) pacific boilers. I've even been considering one of these as the foundation for a V2, A2/2 or early A2/2 body if necessary. So whats' the logic? Okay, the dome has to be neatly changed, the cab sides, or whole cab may have to be altered, but this body is free from the boiler under-skirts of the old Triang Hornby Flying Scotsman body, and unlike the later A3 variants of this body the whole boiler is in one piece. Every version of the tender-drive body that I've seen with a factory banjo dome has a separate section of boiler-top between the firebox and the second band behind the smokebox, and this section doesn't fit properly, so that there's a height step in the boiler-top adjoining a boiler band at each end of that section (plus a horrible joint halfway down each side of most of the boiler, not hidden by an ejector pipe on at least one side). The step-joints next to boiler bands are partly hidden by the presence of those bands, but as all of the conversions that we are talking about are likely to require boiler bands in different positions to the original ones near the front of the barrel, those steps in heights is going to be a nuisance.

Re: 2002's 4mm projects - various A4s (de-valencing) etc

Posted: Thu Mar 22, 2012 12:28 am
by 2002EarlMarischal
Saint Johnstoun wrote:4-8-2

My original tender drive 4-8-2 used 2 old old Margate Tender Drive A1 bodies and the cab from an A4. My current project is using two current China A3 bodies and a Bachmann A4 cab.

Somewhere in the dark and distant past there are piccies of my original conversion on this site.
Many thanks for the e-mailed pic Saint Johnstoun! :D How about some of your current project please?

On that specific design of 1939, I find it hard to believe that the finished loco, should it have been built, would really have been given that strange angled running plate above the front buffer beam. It certainly does not have the usual elegant flow of SNG's other designs.
Atlantic 3279 wrote:Given the virtual non-availability (as far as I can find) of the new China-made super-detail A3 bodies, the high prices that they can command when they rarely appear, and the "fragility" which is objected to in a previous post, I would strongly suggest that it is worth looking at the option of two, cheap, Margate Hornby round-dome (A1) pacific boilers. I've even been considering one of these as the foundation for a V2, A2/2 or early A2/2 body if necessary. So whats' the logic? Okay, the dome has to be neatly changed, the cab sides, or whole cab may have to be altered, but this body is free from the boiler under-skirts of the old Triang Hornby Flying Scotsman body, and unlike the later A3 variants of this body the whole boiler is in one piece. Every version of the tender-drive body that I've seen with a factory banjo dome has a separate section of boiler-top between the firebox and the second band behind the smokebox, and this section doesn't fit properly, so that there's a height step in the boiler-top adjoining a boiler band at each end of that section (plus a horrible joint halfway down each side of most of the boiler, not hidden by an ejector pipe on at least one side). The step-joints next to boiler bands are partly hidden by the presence of those bands, but as all of the conversions that we are talking about are likely to require boiler bands in different positions to the original ones near the front of the barrel, those steps in heights is going to be a nuisance.
Much obliged Graeme for the usual thorough and helpful guidance - "Margate Hornby round-dome (A1) pacific boilers", it is! :D

Re: 2002's 4mm projects - various A4s (de-valencing) etc

Posted: Thu Mar 22, 2012 12:53 am
by 2002EarlMarischal
For anyone else who's interested, "Flying Warship" has some more A1/3/4 chassis for sale on eBay:

http://www.ebay.co.uk/itm/HORNBY-LOCO-D ... 3f15452358

Re: 2002's 4mm projects - various A4s (de-valencing) etc

Posted: Sun Apr 22, 2012 11:42 am
by 2002EarlMarischal
I have, at last, some loco-drive Hornby A1 bodies available so I can progress the first 4-8-2.

I'm sure I have read somewhere on this forum, (but cannot find reference using the search facility), that there are techniques for removing handrails and handrail knobs, without damage to the body.

In the past I have found that simply trying to pull the knobs out results in broken stumps that then have to be filed flat.

I think that warming them up with a soldering iron may have been suggested? Or was there an alternative method using some type of solvent for the glue?

This needs to be my first step before the scary sawcuts! Any advice would be much appreciated. :)

Re: 2002's 4mm projects - various A4s (de-valencing) etc

Posted: Fri May 04, 2012 11:32 pm
by 2002EarlMarischal
At last, I have had a little time to attack my Doncaster bodies, and here are some shots of one of the identical donor bodies and the stretched A1 that has resulted:
[120] Mountain 11.JPG
[121] Mountain 12.JPG
[122] Mountain 13.JPG
The running plate joints need to be tidied up but I have concentrated on getting the main boiler joint right first. I want to ensure a good solid joint before I start sanding down boiler bands etc.

As it stands, the loco does not have the V-fronted cab proposed in the 1939 drawing or the strange angled front running plate over the buffer beam. I just can't see the latter having made it into production but the cab most probably would have done.

One major problem identified by St Johnstoun is that the Hornby motor will not fit into the narrower internal space over the correct driving wheel, so as it stands this model is not motorised. Hmmm. :?

I don't think it looks too ungainly.

Re: 2002's 4mm projects - various A4s (de-valencing) etc

Posted: Sat May 05, 2012 12:53 am
by manna
G'Day Gents

That looks tasty, with loco's that tough, the LNER would have had to lengthen the platforms at KX out to Gasworks Tunnel, and for you, to get it working dare I say it..................Motorized Tender......... runs like hell :lol:

manna

Re: 2002's 4mm projects - various A4s (de-valencing) etc

Posted: Sat May 05, 2012 4:28 am
by giner
AWESOME machine!! I can feel the power.

Re: 2002's 4mm projects - various A4s (de-valencing) etc

Posted: Sat May 05, 2012 10:42 am
by Atlantic 3279
Yes, I like it!

'Tis a bit awkward about the motor width. I'm not sure whether the avoidance of that problem would actually have justified the extra work needed to add the fourth coupled wheelset to the front of the original unit, shifting cylinders and motion bracket forward in the process (or cutting and splicing two chassis at a point further forwards). Measuring my spare Margate "Royal Lancer" body there is certainly width to accommodate a 14mm wide Mashima flat-can over the leading coupled wheels, and a 1428 or 1430 if you can get one would gives bags of power (and just as importantly, torque). As you've evidently got the motor out now anyway, you must be well placed to see whether a bit of ingenuity would allow the transfer of the worm gear to a Mashima (preferably without wrecking the bearings/armature in the old motor through rough pulling of the gear), and the mounting of same in the chassis. If you are stuck, let's confer further on the point, I'd be interested to see this one solved without recourse to notchy Ringfield tender drive or expensive Bull-Ant unit. The power is after all best placed in the loco.
If you end up with a spare Hornby motor or two, with or without worm gear, either you'd have a handy spare for the future or you could flog them off. Good luck.

Of course, if you don't fancy interfering with motor and gears, you could scrape / chisel / file / mill an extra 1mm out of the thick boiler sides to open the motor slot up to something like 17mm, as far forward as the new leading edge position of the existing Hornby motor. That does have the cosmetic disadvantage of raising the visible lower edge of the boiler to splasher-top level or thereabouts in areas both fore and aft of the third coupled axle.

Re: 2002's 4mm projects - various A4s (de-valencing) etc

Posted: Sat May 05, 2012 1:02 pm
by Saint Johnstoun
I was lucky enough to get two China S/d bodies to play with so the motor problem does not manifest itself with my conversion. Don't forget that the smokebox is very long and needs superheater cover plates adding. I'm only using one body with a smokebox extension made from an old Steradent tube.

The spare running plate off my Great Northern conversion is getting put to good use on the 4-8-2 too.

Re: 2002's 4mm projects - various A4s (de-valencing) etc

Posted: Sat May 05, 2012 3:46 pm
by Atlantic 3279
Just been looking at your image 88 and thinking again EM. Although you've filed flat the "bed" area for the motor in the aft portion of chassis, you still have the option to unscrew the rear upright motor bracket and it move it backwards to the position available on your aft chassis piece. If you can then pull the worm gear with sufficient care, and find (or slim down) a piece of rod to match precisely the armature shaft diameter as well as piece of tube that fits (or can be bored to fit) perfectly over the shaft, there's the possibility of extending the shaft at the front of the motor to mount the worm gear where you want it, forward over the pinion wheel. You'd have to instal some sort of bearing where the front of the motor previously was, to support the extended shaft and keep the gears correctly meshed, and probably a new bracket to hold the front of the motor in its new position, but (surely?) those tasks can't be impossible. You can then retain your original motor, but inside part of the body in which it WILL fit without and butchery, save for any minor trimming to relieve tight spots that (by the look of my spare body) might occur around the base of the inside of the backhead. :) :?: :?:

Re: 2002's 4mm projects - various A4s (de-valencing) etc

Posted: Sat May 05, 2012 5:22 pm
by 2002EarlMarischal
Atlantic 3279 wrote:Yes, I like it!

'Tis a bit awkward about the motor width. I'm not sure whether the avoidance of that problem would actually have justified the extra work needed to add the fourth coupled wheelset to the front of the original unit, shifting cylinders and motion bracket forward in the process (or cutting and splicing two chassis at a point further forwards).
Agreed, I may be wrong but I could not quite see a viable route by adding the wheelset in front, and I felt the motor should drive onto the second axle from the front.
Atlantic 3279 wrote: Measuring my spare Margate "Royal Lancer" body there is certainly width to accommodate a 14mm wide Mashima flat-can over the leading coupled wheels, and a 1428 or 1430 if you can get one would gives bags of power (and just as importantly, torque). As you've evidently got the motor out now anyway, you must be well placed to see whether a bit of ingenuity would allow the transfer of the worm gear to a Mashima (preferably without wrecking the bearings/armature in the old motor through rough pulling of the gear), and the mounting of same in the chassis. If you are stuck, let's confer further on the point, I'd be interested to see this one solved without recourse to notchy Ringfield tender drive or expensive Bull-Ant unit. The power is after all best placed in the loco.
If you end up with a spare Hornby motor or two, with or without worm gear, either you'd have a handy spare for the future or you could flog them off. Good luck.
There seems a lot of merit in the Mashima route Graeme. Not having ever fitted one though, could you tell me whether it would fit in the rear upright motor bracket or would I have to fabricate a new one?
Atlantic 3279 wrote: Of course, if you don't fancy interfering with motor and gears, you could scrape / chisel / file / mill an extra 1mm out of the thick boiler sides to open the motor slot up to something like 17mm, as far forward as the new leading edge position of the existing Hornby motor. That does have the cosmetic disadvantage of raising the visible lower edge of the boiler to splasher-top level or thereabouts in areas both fore and aft of the third coupled axle.
I had wondered about that but Saint Johnstoun had rather put me off. I think he may have tried it and found it impossible to achieve a satisfactory result.
Atlantic 3279 wrote: Just been looking at your image 88 and thinking again EM. Although you've filed flat the "bed" area for the motor in the aft portion of chassis, you still have the option to unscrew the rear upright motor bracket and it move it backwards to the position available on your aft chassis piece. If you can then pull the worm gear with sufficient care, and find (or slim down) a piece of rod to match precisely the armature shaft diameter as well as piece of tube that fits (or can be bored to fit) perfectly over the shaft, there's the possibility of extending the shaft at the front of the motor to mount the worm gear where you want it, forward over the pinion wheel. You'd have to instal some sort of bearing where the front of the motor previously was, to support the extended shaft and keep the gears correctly meshed, and probably a new bracket to hold the front of the motor in its new position, but (surely?) those tasks can't be impossible. You can then retain your original motor, but inside part of the body in which it WILL fit without and butchery, save for any minor trimming to relieve tight spots that (by the look of my spare body) might occur around the base of the inside of the backhead.
Yes I had been mulling over that same idea, rather similar to a propshaft. Trouble is I have never dismantled a motor/worm gear - are special tools required? :oops:

Some careful consideration of alternatives is needed here, and at the snail's pace my projects move at :roll: , there should be ample time for that!

Altough I currently have nowhere to run my models, I am not sure that in the illustrious company I have on this forum, I can get away with a static model which is the easy option!

Many thanks for the constructive advice as always Graeme. :D

Having been in a client's IT Meeting all day today, it has been relaxing to file away the boiler bands and moulded handrails, removing the round dome in the process. Of course, the boiler glue joint was not strong enough to stand that kind of manhandling! No big deal though! :)

I'll try and post some more pics later including the two body halves showing where I made the cuts.

Re: 2002's 4mm projects - various A4s (de-valencing) etc

Posted: Sat May 05, 2012 5:44 pm
by Saint Johnstoun
I have to admit that I nearly got there with the old body conversion of the 4-8-2 but it would just not sit down low enough and if I had taken off any more I would have been through the top of the boiler. You see my original plan was to just upgrade the original model with a new tender and a new loco drive chassis but getting the motor to fit in just beat me. Unlike my Turbomotive whose body fitted straight onto the new chassis there is no direct connection between the new and old FS bodies.
Anyway, for what it is worth I would suggest Graeme's idea of moving the motor as this approach does not seem unsurmountible.
I have a few spare banjo domes if you need one 2002? (both types - original and later).

Which reminds me - another variation not done by Hornby is that with the original waisted banjo dome. Strictly speaking my 2508 should have one!

Re: 2002's 4mm projects - various A4s (de-valencing) etc

Posted: Sat May 05, 2012 6:19 pm
by 2002EarlMarischal
Saint Johnstoun wrote:... I would suggest Graeme's idea of moving the motor as this approach does not seem unsurmountible. I have a few spare banjo domes if you need one 2002? (both types - original and later).....
Thanks Allan for giving me the benefit of your experience, and for the kind offer re domes. :D Fortunately I have some spares myself, so I'm alright on this occasion - much appreciated though!

Here are a few pics of the 2 body halves which look a bit rough now I've attacked them with a file!
[123] Mountain 14.JPG
[124] Mountain 15.JPG
[125] Mountain 16.JPG
I'm not sure whether to bother re-gluing the main joint at this stage, as removing the cab for an A4 type will undoubtedly place too much stress on it again. I bought a cheap damaged A4 recently off eBay but it's too good to chop up for the cab.

Re: 2002's 4mm projects - various A4s (de-valencing) etc

Posted: Sun May 06, 2012 9:58 am
by Atlantic 3279
Pulling the worm gear without damaging the gear spiral or the motor bearings is easiest if you have the proper puller. Otherwise, the key points are to find some means of rigidly holding / supporting the "back face" of the worm gear (i.e. the one that faces the motor) whilst applying pressure to the end of the aramature shaft only, so as to push that through the worm gear. I'd imagine it could probably be done upright, using a strong "forked" piece of metal across vice jaws (or some other gap) to support the back face (bottom face in this case) of the gear with the motor hanging down, and then gently tap / drift the shaft out using a suitable slim tool or piece or rod. Don't wallop it too hard, and arrange for a soft landing for the motor if it suddenly gives completely.

I suspect that even the 30mm long Mashima is a shade shorter than the Hornby motor, so fabrication of at least one simple bracket might be needed. When building chassis I started by trying to produce brackets that, in hindsight, were needlessly elaborate. I later standardised on something much simpler and very easy to make. Can you post a picture of the Hornby motor and worm? Is the motor itself supported only by that rear bracket by the way, the "gearbox" providing the necessary front support to the shaft and gear? A Mashima normally comes with a shaft both ends, if you don't want one of them and it is in the way you cut it off with a cutting disc. One end of the motor case has four tapped holes for mounting screws. In this case it might be easiest to put that end at the rear, and make a simple bracket to replace the Hornby cast rear bracket. What must happen at the front is the interesting thing to work out........