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Is your Bachmann A1?– a follow up to adding weight to Bachmann A4s


Silver Sidelines

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Following my last post with ideas for improving the haulage capacity of the Bachmann A4s (old and new) I am suggesting ways here which I think improve the performance of the Bachmann A1s.

 

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Coming from the North East I have to say that I think Thompson’s A1 Pacifics were one of the most handsome and certainly most powerful engines to grace the East Coast Mainline. The photograph above dating from around 1961 shows Silurian, 60121, at the south end of Darlington Station (light engine), waiting for the right of way back to its Home Shed 50A, York.

 

I am very impressed with my Bachmann A1 models which seem to both capture the character and the power of the prototype engines. Having said all that I still found it necessary to make a few alterations to improve their tractive effort

 

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The first and most obvious alteration to make is to remove the two springs, one from the front bogie, and the other from the Cartazzi Axle. This way the full weight of the model engine is applied to the six driving wheels.

 

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At the same time you should check that rear of the engine is not resting on the tender. Straight out of the box from Bachmann in a number of cases the cab ‘fall plate’ was resting on the tender (labelled M). Supporting the engine from off the tender is not a good idea and prevents the rear driving wheel from making full contact with the track, drastically reducing tractive effort. You might also find that with the engine resting on the tender there is a tendency to derail on small radius points.

 

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The fall plate is shown more clearly above. It can either be completely removed or it can be bent up out of the way.

 

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With the engine turned upside down the two screws labelled ‘A’ should be slackened off to loosen the cab and hence allow the fall plate to be extracted (permanently or simply to alter its shape). The fall plate is very stiff metal (steel?) and it is not a good idea to try bending it whilst still attached to the engine.

 

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The above task is made easier by first removing the locomotive body. With the body removed it is a relatively easy task to add a little extra lead ballast to the back of the cab labelled ‘C’ and into the open boiler space labelled ‘B’. A word of caution – the Bachmann A1 is already a heavy engine. Too much lead added into the boiler will make the engine ‘front heavy’. This will cause the rear driving wheels to lift from the track, negating any benefits from adding the extra weight.

 

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Two reminders: first - the wire at X needs disconnecting from the chassis before attempting to remove the body. It should just lift out from the chassis.

 

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Second - when reassembling the body and chassis it is necessary to ensure that the reversing lever ‘Y’ is tucked into the correct slot behind the motion bracket.

 

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One of my favourites – Kings Courier, 60144. This model was purchased ‘mint’ off eBay and arrived with one of the smoke deflectors loose in the box.

 

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Aberdonian, 60158, another favourite and my oldest Bachmann A1. There are numerous threads on the ‘web’ about this model being underpowered and motors overheating. Certainly the motor in this model is much the smallest of my Bachmann models and lacks the torque of King’s Courier. However my model doesn’t overheat and with the added ballast it performs nearly as well as the later models – must have been lucky.

 

There are two old videos on YouTube comparing the engines:

 

and

 

PS It looks as though I shall have to invest in a feather duster like other good photographers.

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Agreed, I've been thinking of doing the same thing with my Bachmann Tornado. It is one of my worst haulers, the only 6+ - driving wheel loco to equal it being the Bachmann 3F 0-6-0. My garden railway has 1 in 50 gradients, and the most these two can manage is 3 coaches. Tornado has very shiny wheel treads, which probably doesn't help.

 

Incidentally, to assess improvements without going into the garden every time, I have made a simple test rig. A straight and level piece of track is attached to a shelf, and a controller connected. A length of strong thread has a loop at one end to fit over the loco coupling hook, and runs along the track to the end of the shelf, over a piece of low-friction tape on the edge, and hangs vertically with a container tied to the end. I have used a spray paint tin lid which weighs 7g, and I have to hand about 6 large ball bearings weighing 8g each. You can use anything similar, providing you know the weights. Get the loco to lift the container with increasing numbers of weights, until it can't manage, then subtract one. If it lifts it but with the wheels slipping, I count the last ball as a half-ball. Tornado only manages 2 balls, with slipping wheels, so the weight of train it could pull up 1 in 50 is

 

(7+1.5X8)X50-(weight of engine + tender).

 

To get the number of coaches, simply divide by the average coach weight (I use a figure of 150g), and round down the result to the nearest integer. To make the calculation easy and record the results, I have set up a spreadsheet in Microsoft Excel.

 

I have found that the results agree quite accurately with tests in the garden using real coaches.

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I think you probably have been lucky with your Aberdonian, Ray. At the time of issue -10 years ago? - Bachmann offered to re-motor any of the first batch of A1's free of charge because of the problems people were having. I took mine in to the Barwell office where they joined a mountain of others being readied for sending to China for the work to be done.

 

I've carried out similar mods to those described above and fully concur that they are fine engines the finish and detailing of which most kitbuilders would struggle to match.

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John - Thanks, yes I have read lots. My Aberdonian was second hand and I have wondered whether I should be expecting something to go wrong. Fingers crossed.

 

 

Regards

 

Ray

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I have cheated for a long time as my layout, due to the size has a sharp incline and 3 years ago I came up with a powered brake coach. It is composed of a Bachmann chassis dropped into a 57ft Hornby brake coach so with DCC I was able to recode the coach to the Loco pulling its number and operate with a 12 coach load with minimum effort. Cheating but saves double heading and also looks good

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Incidently you may be/or not  aware Bachmann had a recall on Aberdonian and it went back to China for a upgraded motor. I sent mine back and it came back worse with bits missing so one reason for doing it yourself!!

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Great idea - the powered brake coach - what gradients do have?  Much better than the old Kitmaster powered goods van.  Yes - I have read on the web about Aberdonian.  Mine has a small motor that really is not up to it - but touch wood does not overheat.  On the other hand I have a 57xx from the same vintage which overheated - I opened up the can motor and inserted a PTFE washer - seems to have sorted the issue.

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Ray

I've only just discovered this post and thank you for it - I have 5 Bachann Peppercorns on my layout ( http://www.rmweb.co.uk/community/index.php?/topic/73196-waverley-shed-somewhere-in-edinburgh/page-2) and some of them struggle to haul their own shadow!

 

THis is OK in a loco shed layout, but as I'm on the point of starting a new line( once our kitchen extension is finished) which has a 20' run at 1 in 76 up which I plan to haul 8-coachers, I need to do something about it, and this article is hugely useful, so I've bookmarked it!

 

I note that a number of the Bachmann standards I've acquired have the same problem - have you encountered and fixed that?

 

Peter

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Thank you Peter for the input.

 

I wonder if you could see all the pictures in the above Post - I had to reload here a couple of times to bring all the images in from Flickr - perhaps they had been archived!

 

I guess for Bachmann Standards you mean the 73xxxx series. Super engines to look at but because of the smaller taper boiler rather light weight - a bit like the Halls. I haven't done anything with these engines other than perhaps pack a bit of lead into the space available for a decoder. They don't get used much and my recollection is that the body shell is a very tight fit and that there is some delicate pipework to lever out of the way midway along the boiler?

 

Eight coaches and gradients sounds exciting. One in 76 should be satisfactory. You will also have to think about the rolling resistance of the coaches. I like the Bachmann Mk1s but some of the older models don't always run as freely as I would like. I came across a little tool for cleaning out the axle boxes but in time they might need brass bearings. Most of the new super detail Hornby Coaches are fine although some are very light and with eight coaches you might need to add weight to the ones nearest the engine. Something for later.

 

Speak again

 

Ray

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Thanks Ray

 

Funnily enough now that I've actually got a decent circle completed I've found that if you connect the tenders using the long shank, so the fall plate isn't fouling the tender front, the Peppercorns can pull like a train - 10 coaches from a standing start on a 1:110 isn't bad at all. In that  respect the simplest answer is to lose the fall plate or reshape it, but you will need a decent vice to do that

 

I've not yet let the standards loose. Fortunately I'm modelling the Waverley Route so can genuinely run 4/5 coaches and be prototypical

 

Keep up with the comings and goings at Waverley East...

http://www.rmweb.co....13#entry2053958

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Thanks Peter for the update, - ten coaches and gradients sounds excellent.

 

The 'fall plate' on the A1 is reminiscent of the front bogie on the Bachmann Dukedog and Hornby's latest Britannias where it is not physically possible to compress the bogie spring without lifting the front driving wheels off the track.  Here again the solution is to remove the spring.

- 10 coaches from a standing start on a 1:110 isn't bad at all. In that  respect the simplest answer is to lose the fall plate or reshape it, but you will need a decent vice to do that..

 

Keep up with the comings and goings at Waverley East...

.

Hope you are surviving the weather.

 

You have a splendid layout in not dissimilar surroundings to the one here.  I do dip in and out of your thread.  I will take a longer look over the festive season and try and add a few comments.

 

Speak again

 

Regards

 

Ray

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