Overhauling an old A3 and B12

[Jim de Griz]

As one project draws to a close, inevitably another suggests itself.

Two of my oldest running locomotives are a Hornby B12 and A3 Flying Scotsman. Both have seen over 25 years service at this point and despite having been sent in for periodic cleaning/servicing both are beginning to show their age. Neither runs particularly smoothly at slow speeds, both hate the mass of point work at my station's throat and on more than one occasion both have 'failed' during a running session requiring a spare engine to take over their train.

[Please ignore the flipped image, that seemed to be the only way to get the imagine to display right way up]

Add on the faded paintwork and lettering and I get the feeling they don't need another service, they need an overhaul if they are to stand proudly alongside the newer engines in the shed.

{An aside} Lets state the simple solution, I could fairly simply acquire a newer B12 and A3(or better yet an A1) and in the case of the B12 in particular would get a much more realistic locomotive out of the deal. Both these engines have significant sentimental value and if I can keep them off the shelf and on the layout I would much prefer to do so.

Noting my fairly limited skills, I intend to pursue two lines of work

Paintwork

I've been advised that a small amount of t-cut carefully applied should bring the shine to the paintwork. I'm hoping to avoid having to replace the lining, but I've got pressfix transfers for the lettering and numbers. A thin coat of matt varnish over the top will hopefully give the paintwork a subdued but visible shine.

This would be a good time to have a look at some images and see if there any details need picking out in black, red or bronze.

Electro Mechanical
Beyond the obvious disassembly, clean and oil, I think the major issue that needs resolving is the lack of pickups.

The obvious solution would be to add tender pick ups (I had some success bringing a Hornby Pug back to life by giving it a coal wagon tender with picks ups) The problem is both engines have plastic wheels on metal axles.

I have no idea how I would get these out and even less which axles/wheels I would need to replace them. (Advice on this matter would be very welcome) Then I noticed that the bogies have metal wheels and what looks to be enough space to fit pick ups.

I was wondering if anyone had tried fitting picks ups to old bogies (and the trailing pony for that matter) or any recommendations on which types of pick ups to use? The DCC Concept ones I have look too bulky for the space available and probably a bit too hard to hide.

I'm hoping adding pick up to bogies will sort out the stalling problem. The slow speed running I'm not so sure of, but I figure it would be worth a go.


As I'm going to have both engines disassembled on my work bench, could anyone suggest anything else that would be worthwhile to do to improve appearance/performance?

Jim de Griz

[Hatfield Shed]

First thing to check, wear state of the mechanisms: motor bearings, gears, axle holes, crankpin holes in particular. These were low cost toys and if operated very regularly - unless kept well lubricated - off round axle and crankpin holes are not unusual: and that's the chassis block and flanged driving wheels for scrapping.

But if all that is OK, there's a very good option for parts for carrying wheel pick up on the A3. What's required is a non-runner split chassis Bachmann A4, for its bogie, rear truck and tender wheels. That potentially provides all wheel pick up with no need for wipers, so no incremental friction, but you have to adapt the parts to the Hornby model. Simplest is to fit brass frames inside the plastic tender frames to take the Bachmann split chassis wheelsets.

[mick b]

If both Locos have pick ups (6) on all the drivers that should be more than enough. I suggest check them for contact first , then replace the complete Motors, brushes or the Motor Magnet if still needed.

[Mersey508138]

If I may come in here please, the 1st question I have to ask is what gear both locos have fitted to them.

The reason for this is that I recently purchased a motor from horns and whistles workshop, key in hornby motors on ebay and a listing shows up for this motor amogst all the others.

At £35 a go they are not cheap but they do drastically improve the performance of triang hornby locomotives. I have a standard class 3 2-6-2 tank which I fitted this motor into and straight off the starting blocks hauled 6 Bachmann Suburban coaches with absolute ease and alot smoother than with the X04 motor it originally had when I bought it.

Bill Ewart on his oobill youtube channel reviewed this motor and fitted 2 of them, 1 into the same locos except his B12 is a black loco but that aside he gave a very good review of the motor and his video is well worth checking out.

Bill has also filmed many repair videos for quite a few locos, from the old GWR 0-6-0 pannier tank through to a loco drive hornby duchess aswell as a Bachmann Class 158.

Bill's channel is worth its weight in gold because of the helpful advice and tips that Bill gives and he has also shown how to fit cd motors into locomotives too.

Anyway back to the A3 & B12 this new motor will fit the triang versions only which include thosewith the more modern 1980s / 1990s wheels where 1 side is live and the other insulated but it will not fit in a tender drive A1/3 chassis without some modification to the chassis block where the slots are to allow XO3 and XO4 motors to be fitted.

I only found this out after I had fitted a gear cog to the 2nd driving axle of a tender drive loco chassis and using the motor slots unmodified the motor and wheels would hardly turn so it is important to note that for the locos in the original post it will suitably fit without chassis modifications, except for a gear change if the locos have the grey gear for XO3 motors as the worm gear on the horns and whistles motor is only suitable for the XO4 gear at the moment although oobill does say that it is a possibility that a gear may be developed for locos with the grey XO3 gear but up to now this has yet to be made.

Hope this helps

[Atlantic 3279]

Interesting news about that motor, for those still using locos with originally made with the XO4.

I'd be surprised if that old loco-drive Scotsman has pick-up on as many as six wheels - I imagine the pick-up is limited to the four with the deeper flanges, certainly not enough on uneven track.

[Pebbles]

From what I've seen these motors are similar to those used by Hornby in their J50 and J15, there may be others. Mike Edge has used these motors in some of his builds. At one time single shafted versions were going on the web for a song. When 00Bill initially used this type of motor I believe a two start worm was used, this has since been replaced by a single start worm giving a reduction of 40:1. Whilst there is no reason to believe that the replacement motor won't give good service, as these are fairly high revving motors they could benefit from a higher reduction. As it is I'm rather impressed by the work that mr snooze has been carrying out on XO4 and their like.

[Jim de Griz]

Unfortunately there are definitely only 4 pick ups and I’ve been forewarned that the bearings/brushes on the Scotsman in particular are wearing out. I’ll have a better idea of her material state once she is properly disassembled, but thank you for the heads up on what I should be looking out for.

I’m tempted by a motor swap (assuming the problem is the motor), but I’m a little bit concerned that the motor in question is apparently rated for 4-5 light coaches. My usual express trains are 5-6 in length and they are made up of coaches that are not always the lightest/most free running….

Incidentally, thank you for the steer towards oobill as he has a video on overhauling the Scotsman that I suspect will be very useful.

Jim de Griz

[Mersey508138]

No problem.

In my post where I mentioned that motor which oobill reviews, I stated that the class 3 tank locomotive ran much better with 6 suburban coaches, the actual number of suburban coaches is 7.

I have even coupled the loco to 8 mk2a coaches and it moved them with no problem at all so in a triang scotsman loco, I would say 7 or 8 mk1 coaches should be easily within the motors limits. I don't have a figure for freight vehicles as I have not tested it with those yet but as soon as I do have a figure for freight vehicles without slipping I will post it on here for anybody wanting some figures to work from as a base figure to compare with.

[Jim de Griz]

Thank you again for the steer towards OOBill, very very useful to watch someone who knows what they are doing disassemble the exact chassis I was working on!

This is certainly turning out to be a learning experience. The B12 came apart fairly straight forwardly and I quickly found a number of issues needing addressing

1. The pick ups. the brushes and the motor in general were all VERY dirty.
2. Age has made the pick ups, wiring and a lot of other components very fragile, including the insulation between components. (over use of WD40 in my youth will not have helped here)
3. The chassis is live, so getting at all the contacts means taking off the wheels.

OOBill advises not to do the last, but as I wanted to ensure I'd cleaned everything I reluctantly took the wheels off anyway. In short, I wouldn't do that again! Aside from requiring an excessive amount of force to get off they have been an utter nightmare to get back on square. After over an hour of swearing I managed to get them sort of square....only to have to take them off again to hunt down a short circuit and after refitting them had to remove them again because I didn't do a good enough job of quartering them....

On the subject of harm, Methylated Spirits did an excellent job of cleaning all electrical contacts, but the repeated disassembly and reassembly of the components was not appreciated. Long story short, I've had to replace all the wiring and the electrical pick ups as they kept breaking. Fortunately the brushes didn't as I don't have spares for them laying about....

Long story short, I'm better at soldering that I used to be, and the chassis runs once more.

Its performance is certainly a massive improvement, but there are definitely dead spots on the motor. With the contacts all new, the wiring new and the brushes/contacts as clean as I could get them, I think it is time to look at replacement. Unfortunately, Horns and Whistles Workshop have sold out, so I'm hoping they get some more stock soon.

But, she does run again and hopefully when I work out how to fit picks up the bogie she will run better (or at least stall less on points)

However, there is one final problem.

I washed the body shells in hot water with washing up liquid. I've done this before without issues, perhaps I left them to soak too long this time, maybe its that I live in a hard water area, but they are both now covered in a white layer. Internet search suggests it is either limescale (bad) or the varnish reacting (very very bad).

Scrubbing with vinegar has had some effect (that's why the Scotsman looks cleaner), but not as fast as I'd like and it is likely contributing to the increasing brittleness of small parts. I'm soaking them in White Vinegar at the moment, giving it another hour and then I'm going to have to assume it is the varnish and pull out the nuclear option, Dettol. Either way I think I'm committing to a full repaint at this point.

....well this was supposed to be an experience gaining exercise and I definitely feel like I have more experience than I did on Friday...

Jim de Griz

[Jim de Griz]

Well the vinegar didn't work, so into the Dettol.

2.5hrs with a scrub at the 1 and 2hr mark hasn't completely removed the white covering, but it has removed the vast majority of it, along with all the lining and transfers.

It has also made the black paint tacky and in places removable (making a horrible black tar that was got everywhere)

But, critically it hasn't made the plastic soft or brittle (anymore than it already was anyway)

I suppose I should have continued dunking and scrubbing until the black paint was gone, but frankly I didn't want to push my luck.

I'm going to let the sides dry/set for a day or so. Then I'll start to sandpaper them down ready for priming.

On the plus side, the electronics are coming along. Took far to long to add them, but I've added an extra pick up on each side of the lead bogie, which does seem to be reducing stalls on pointwork etc. Will put more work into hiding the wires once I've got the body shells back.

Jim de Griz

[mick b]

Try this, it may be easier for paint stripping on plastic.

https://www.rmweb.co.uk/forums/topic/33 ... ent-356867

I have used this method on a number of models , no issues at all. Plastic is untouched.


Dont use sandpaper !! wet and dry much better and will not destroy all the detail !!.

[Mersey508138]

Hi Jim

Can I ask please how you made the pickups for the leading bogie on the B12 as I would be interested in trying that on 2 of my B12s which are the only runners out of the 3 I have at this time.

Re Motors for the B12 & A3 : Recently oobill reviewed completely up to date motors released by Peter's Spares which have been produced as a full replacement for the old triang X03 and X04 motors and are fitted with the relevant worm gears.

They are priced at £28.50 each and like the horns & whistles workshop motor they seriously improve the performance of older locos which may still have XO3 and X04 motors fitted.

I am hoping to purchase some of those motors myself soon so that I can get my fleet of motorless locos ( about 6 or 7 in total ) running again and upgrade my triang A3 aswell as a 1990s R398 Scotsman locomotive which I converted to run with an XO4 motor in the locomotive and make both of these run much quieter than they currently do. All in I would guesstimate that I have about 9 possibly 10 locos to upgrade aswell as a triang GWR Hall class loco which hasn't run for quite some time.

[Jim de Griz]

Try this, it may be easier for paint stripping on plastic.

https://www.rmweb.co.uk/forums/topic/33 ... ent-356867

I have used this method on a number of models , no issues at all. Plastic is untouched.

Dont use sandpaper !! wet and dry much better and will not destroy all the detail !!.

Caustic Soda + Methylated Spirits, ok I'll give that a go, thank you.

By hard experience I've found my apartment isn't as well ventilated as I thought it was, do I need to take any more precautions than I usually do with Methylated Spirtis?

Also a good shout on the wet and dry, really should keep some handy for jobs like this.

Hi Jim

Can I ask please how you made the pickups for the leading bogie on the B12 as I would be interested in trying that on 2 of my B12s which are the only runners out of the 3 I have at this time.

Re Motors for the B12 & A3 : Recently oobill reviewed completely up to date motors released by Peter's Spares which have been produced as a full replacement for the old triang X03 and X04 motors and are fitted with the relevant worm gears.

They are priced at £28.50 each and like the horns & whistles workshop motor they seriously improve the performance of older locos which may still have XO3 and X04 motors fitted.

I am hoping to purchase some of those motors myself soon so that I can get my fleet of motorless locos ( about 6 or 7 in total ) running again and upgrade my triang A3 aswell as a 1990s R398 Scotsman locomotive which I converted to run with an XO4 motor in the locomotive and make both of these run much quieter than they currently do. All in I would guesstimate that I have about 9 possibly 10 locos to upgrade aswell as a triang GWR Hall class loco which hasn't run for quite some time.

Thanks for the heads up on Peter's Spares, I'll have to give those motors a look.

Sorry I had trouble getting a good photo without disassembling the model, this was about the best I could manage, but to be honest the concept was simple, just fiddly because of how small the clearances were. I originally intended to add pick ups to all four wheels, but the limited space convinced me to just fit picks up to the rear pair.

I used 0.35 diameter phosphor bronze wire. Each pick up is about an inch and a half in length and bent at each end so you have two short parallel lines with a diagonal connecting them.

I prefer to put a small loop in at the end that will rub against the back of the wheel, but I'm not convinced that is needed. (You can just make out the loop on the back of the wheel opposite in the picture)

I used a small strip of plasticard (0.25mm thick) as insulation and attached that to the side of the bogie with superglue. The pick up was then fixed to the plasticard with superglue and the wire soldered on. That bit is tricky because too much heat will melt the plasticard and/or superglue. Neither is a good idea. (Seriously vaporised superglue is bad news)

I did try soldering first, then supergluing to the plasticard, but that made it very difficult to get the contact in the right place. Not impossible, just harder.

In retrospect, I think I would have been better off using 0.5 diameter wire (as I did on the main wheels) and I should have put more of a bend. If I can find some superfine PCB I'd replace the plasticard with that as well to remove the issue of soldering near superglue.

Hope that helps and best of luck.

Jim de Griz

[mick b]

Yes, outside only due to fumes as the Soda reacts with the Meths, it is short lived reaction , but not pleasant and to be avoided.

[Mersey508138]

Hi Jim

It certainly does help, many thanks for that. The 2 × B12s currently pick up from 6 wheels per rail already but I have been looking at ways to get them picking up from all wheels if possible.

I have fitted pickups into the tenders of all my B12s but if you require any, I can post a picture of the pickup arrangement on 1 of the working locos either later or tomorrow as I don't have a picture of the pickups at the moment.

For the Triang A3 I recently created a pickup arrangement for 1 of these locos which has a recently purchased triang A3 chassis. The tender chassis is from 1 of the most recent Hornby A3 / A4 locos which have tender pickups. The coupling pin was removed as this was not needed but during the process the plastic around the coupling pin broke away. A repair was carried out by fitting a piece of 80 thou plasticard accross the chassis fixed in place with superglue and left to properly set overnight and further secured with small screws to ensure that the repair would not break away from the chassis.

The plasticard was then drill to roughly 2.5 or 3.0 mm and means that the loco and tender can be nicely close coupled, I also had to add extras weight glued into the tender body and also prevent shorting out the power. During 1 of the previous projects the tender had been used for, the original pickups got completely messed up and could not be repaired so I made my own pickups hence fitting the extra weight up in the body out of the way.

I was surprised when the loco moved as I didn't know if the modifications would work but it does and makes the loco run much better. I can provide pictures of the triang A3 pickups I made and the wiring for it if needed.