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BACHMANN CLASS 4MT TANK LOCOMOTIVE

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BACHMANN CLASS 4MT TANK LOCOMOTIVE


How does it compare with the Hornby Dublo version of 50 years ago?
Reviewer - Gary Leigh


Introduction


In 1954 Hornby Dublo introduced their first British Rail designed locomotive and it happened to be the Class 4MT tank locomotive. Many model railway observers at the time thought that Hornby Dublo would introduce the Britannia Class main line locomotive and were slightly shocked that priority had been given to a tank locomotive. However, a tank locomotive was badly needed in the range at the time and what better choice than the brand new design of Riddles, the BR Chief Mechanical Engineer. The model locomotive was very well engineered and had rave reviews in the modelling press of the day. Hornby Dublo were very proud of the fact that of the first batch of 100,000 produced (yes 100,000! What would Hornby and Bachmann today make of these production numbers?) only 6 were returned under warranty! In fact this locomotive had a strong fan base, featured in a number of sets, and was arguably Hornby Dublo's most popular and best ever locomotive.

Almost 50 years later Bachmann introduced this same model for the current generation of modellers. The demands of today's modellers are somewhat different to those of 50 years ago, but allowing for this how does the best of its generation compare with the best of today's generation?


The prototype - history

To give you some background of the prototype the locomotive was first outshopped from Brighton works in July 1951, 155 of these locomotives were built in Brighton, Derby and Doncaster works between then and 1957 and became general workhorses on all the regions of British Railways, except the Western. Not things of beauty with their somewhat unattractive "rear ends", they were a product of the development by British Railways of a series of twelve "Standard" locomotive designs embracing the best practices of the pre-nationalisation railways.

Designed by RA Riddles, British Railways' Chief Mechanical Engineer, these tanks were one of the most successful of the "Standards", doing well all that was asked of them.

The Standard 4s shared much of the basic design of the LMS Railway's Class 4 2-6-4Ts built under both Stanier and Fairburn (some of the latter locos were built at Brighton after nationalisation) but with considerable improvements. They had smaller cylinders and higher pressure boilers, were more economical in operation and were popular with footplate crews for their better running and improved cab facilities.

Classified as 4MT on the Eastern, Midland, and Scottish Regions, their Southern classification was 4P/4F. Most were to be found working on the Central and South Western sections of the Southern Region, the LTSR lines of the Eastern Region and the Glasgow commuter lines in Scotland. When the LTSR lines were electrified many of the displaced Standard 4s were transferred in July 1962 to Shrewsbury, in the Western Region, who then lost them again to the Midland Region during the boundary changes that took effect from 1 January 1963. In the same boundary changes the Western Region was handed all of the Southern Region west of Salisbury, also inheriting the locomotives based in that area, including Standard 4Ts. However, the mainly dieselised Western Region seemed determined to send them to the scrapyards as quickly as they could either get their hands on DMUs to replace them, or close down the lines where they worked.

Fortunately 14 of these locomotives ended up at Woodham's Scrapyard in Barry and have since been purchased for restoration. They are an almost ideal engine for preserved railways in that they are a relatively modern design, economical, and capable of handling the sort of loads found on preserved railways.


The model

First impressions - for those used to the diecast representations by Hornby Dublo and Wrenn the first thing that strikes you when you open the Bachmann box is the amount of plumbing and pipework that surrounds the loco . No longer is this represented as impressions within the body. Now all the pipework is fitted separately with great care. Those used to the brutish, tough, good looks of the model of 50 years ago will take one look at the Bachmann model and wonder how to handle it and pick it up. It does look fragile. However Bachmann have done a very good job with this detail and as you can see when you compare the prototype with the images of the model the detail is all present and correct unlike the Hornby Dublo model. Looking at the images above on the left the Dublo model has no brake gear and this together with under chassis detail has already been fitted to the Bachmann model. The motion gear has a much finer and more slender look to it In terms of the shape you will have to make up your own mind.

The body of each is very similar in dimension however the Dublo example has a broader chimney and a flatter dome and the Bachmann example has a narrow chimney and a taller dome. The flatter dome on the Dublo loco gives the whole body the impression of riding higher that the Bachmann but ultimately this is only an illusion and both boilers are at the same height. Looking at the rear of the loco and the coal bunker the Bachmann model has steps and separately fitted handrails whereas the Dublo example has an ugly great hole in the middle and unfortunately the eye does focus on this. The body fixing screw is somewhere to be found inside this vast blot at the rear of the Dublo 4MT and modellers of today simply would not be prepared to accept this type of compromise. When looking at the front the much finer detail present on the current model clearly stands out with separately fitted handrails. The images below paint a similar picture with much finer printwork and lining, and better detail, on today's model. The Bachmann cab is also glazed. However the Dublo body does have chips in the paintwork and after 50 years it is unlikely that the Bachmann will look similarly worn so this has been taken into account in the scoring. The scores so far therefore:-

APPEARANCE - HORNBY DUBLO 5 | BACHMANN 9
DURABILITY - HORNBY DUBLO 7 | BACHMANN 6


Modellers of today are very demanding and as a reality check it would pay every modeller to review and look at what was offered 50 years ago. We would then be far more appreciative of today's offerings. However, there is another consideration apart from appearance and that is performance. Now the Bachmann loco weighs in at 365g and the Dublo loco at 550g which is almost exactly 50% heavier. Does this effect starting performance? The locomotives were each tested with the Bachmann EZ-Command Control Console. From a standing start the Bachmann loco required the control knob to be turned to the pencil line shown in the image to the left. On the curve it required a touch more power to get the loco moving as shown. The Dublo loco being almost 50% heavier did require more power from a standing start and the control knob needed to be turned to the start of the grey band but once moving it seemed to accelerate more quickly and continue at a faster pace indicating higher gearing. In fact at top speed the Dublo loco would whizz around the track at more than twice the speed of the Bachmann loco and would topple over on corners. This you don't want with a heavy diecast loco as you could break something. So taking into account the gearing and the greater weight the Dublo loco does remarkably well for a 50 year old. And of course it is designed to operate on tighter radius 1 curves. This is something the Bachmann loco has difficulty accommodating as a result of the rear pony design and on a small layout with tight curves the older model will win hands down.

The real test though is pulling power. What sort of weight can each of these locomotives pull from a standing start in a "Strongest Man in the World" type of challenge? I thought it best to start with the Dublo loco as their locos were advertised at the time as being able to pull a small boy on a trolley and as I did not recall any current ready to run manufacturer making such claims then clearly the Dublo had to be king here. But by how big a margin? To be honest I did not want to burn the motor out on the Dublo loco so I limited the load to a 1.5kg bag of flour placed on a flat bogie wagon and the Dublo loco pulled away with plenty of room to spare. To put this in context we are talking the equivalent weight of maybe 12 Hornby Mk1 coaches. Ample in terms of the typical loads that the prototype was asked to handle. So, what would the much lighter Bachmann pull from a standing start? I started off with 1.2kg and much to my surprise it pulled away rather easily. Therefore I moved straight up to the 1.5kg load and much to my amazement it did pull away. Yes, the Bachmann loco was struggling but it was capable of pulling this sort of load from a standing start. Now for a 365g loco without traction tyres this is some going in my estimation and top marks to Bachmann for delivering this type of pulling power. This loco should cope with any prototype rolling stock arrangements asked of it with ease.

PERFORMANCE - HORNBY DUBLO 7 | BACHMANN 8

80104 at Harmans Cross on the preserved Swanage to Wareham line.

80015 at the head of a passenger train arriving at Clapham Junction in 1966.
photograph by Ray Soper

Finally you might ask why I did not remove the bodies and reveal the chassis arrangements. The truth of the matter is I lost the instructions for the Bachmann 4MT and when I looked at the chassis there were so many screws and so much detail that I simply did not want to take a chance and damage anything. The Dublo loco with its one fixing screw at the back, whilst not pretty, gets top marks here for simplicity and ease of maintenance. I however felt that it would be unfair to unfrock the Dublo loco whilst leaving the Bachmann version covered up so on this occasion your get to see the chassis of neither! There are also stories that the Bachmann loco body is difficult to remove even when you have the instructions and its a rule of thumb that things that are hard to take apart are even harder to put back together so, maybe one day, bit not today.

MAINTENANCE - HORNBY DUBLO 9 | BACHMANN 3

FINAL SCORE - HORNBY DUBLO 28 | BACHMANN 26

If you remove the score for ease of maintenance you totalHornby Dublo 19 Bachmann 23 so really there are no winners and losers. It really depends on your view of maintenance. The engineered Dublo scores high here however the modelled Bachmann makes up for it in almost all the other areas.

Ultimately the Dublo model is not available on general release and if you want to pick up one of these, or a Wrenn version, in good condition you are going to have to pay in excess of £100. Against this the Bachmann example at around £50-£55 is remarkable value considering all the work that has gone into putting a finely detailed model together. It is also a surprisingly good performer and will do 99% of jobs asked of it. The real question that will intrigue a lot of folk and cannot be answered at this stage is which one will be still be running in 50 years time?
 
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