Model Encyclopedia - Bachmann 1:87 DF4/DF4B Class Co-Co Diesel
The Df4B's have been one of the most successful indigenous diesel locomotives on China's Railways. Since 1984, almost 4,000 have been produced and are still made in limited quantities today. They are used on practically every type of work - passenger, mainline freight, industrial and maintenance. As a general guide, Orange painted DF4B's (those in the 2*** road number series) were used exclusively for passenger work and geared for higher speed than their freight counterparts. There is a plethora of liveries and Bachmann has been very good over the years offering many of these.
Model Review - First Series
In June 2002, the first DF4B locomotives were made in model form. They set a new standard for Chinese models from Bachmann and have proved to be their best selling locomotives for their popularity, excellent quality and affordability.
Four different road numbers were produced in two liveries standard passenger (orange/yellow lining) and freight (green/light blue lining) liveries. The paint work is evenly applied with a very nice finish and the lining and lettering is raz or sharp. There is loads of very small, yet perfectly readable text around the bottom of the frame and I was most impressed with the inspection plate on the air reservoirs adjacent to the fuel tank. The two passenger versions differ slightly in that one has white lettering, while the other has black with some tiny gold characters printed on the side door windows.
The builder's plates' are embossed on the sides which is something other models produced since seem to lack and are simple painted on. The roof has excellent details with lots of grab irons, antennas and six horns (which are quite susceptible to breaking off, so handle these carefully). Hand rails on the side and ends of the locomotive are metal. The bogies are press fit and while they seem to be the correct length, they lack depth and many of the components seem to be undersized. The main flaw with these engines is the warp in the body that occurs above the wheels. This is the result of an poorly engineered frame that is hollow around the bogies. Over time, and particularly in hot climates, the body has a tendency to sink in, the results of which can be seen in the second last photo at the bottom of the page.
These engines are extremely heavy - which is a good thing for pulling heavy trains. Electrical pickup is perfect, and they are very quiet, responsive and smooth. There are two very large brass flywheels to help with this. I have noted over time that the motors have worn out on a few of them, and the pulling power has fallen to about half of its original capabilities. They have low wheel flanges - something most of us deeply miss.
Electricity is moved around the engine via a PC board and wires. The lighting is directional, with the main headlight powered by a 12volt incandescent bulb which looks very bright and has a good color. Unfortunately, these can get very hot after a period of time which is no good for the plastic body shells in the long run. They do have some heat insulation around the bulbs, but I'm not sure I would trust this (don't forget to turn them off when not in use!). The marker lights are nice, particularly the inner red ones.
There is enough room inside the shell to accept most HO scale sized decoder, although it may be necessary to position them between the motor and the frame. As per standard Bachmann practice, the DF4B's have an 8 pin socket to accept any NMRA 8 pin decoder.
All versions will accept long shank (#56/156) Kadee couplers. A very fine amount should be shaved off the top of the shank for free movement and a tiny bit on the bottom at the back of the head to avoid clearance with the center un-coupler stantion.
Model Review - Second Series
It took a bit over three years until the second series of DF4B's were released, this time three numbers were produced each with a different livery. An orange passenger version, standard green/light blue 'watermelon' version and a very welcome edition of the green mixed traffic locomotive with yellow lining (color scheme called 'military police', as the locomotive bears similar colors to the uniforms).
The major improvement with these locomotives was the re-tooled frame which included side panels around the wheel sets (compare the 1st and subsequent series with the second last photo at the bottom of the page). This eliminated the body warp problems. As a side note, the body shells from the 1st series are interchangeable with later versions.
This was the first decorated locomotive called "Youth" and has a brass plaque on each end with the emblem of the Youth Communist League. This engine also had a unique horn arrangement with 5 on each end (four forward facing, one reverse). Each of these new models had numbers '1' and '2' printed between the cab windows and doors.
Model Review - Third Series
The third series was decorated DF4b #2106 named in honor of Zhou Enlai, China's first Premier. This model was the subject of a re-run in mid 2011. Somewhere along the way the price nearly tripled from the initial run!
The locomotive is maroon lower and cream upper. Although a very magnificent looking locomotive, I find the paint work much too glossy, but it appears this was a once off as subsequent DF4B's have reverted back to the semi-matt finish. The model features extra handrails around the roof and four air horns at either end mounted to a ribbon-like facade.
Model Review - Forth Series
The forth DF4B production run was also a single version, like the previous one. It was the beginning of the Tibet series, which was inspired with the opening of the world's highest altitude railway to Lhasa. Loco #1083 was the first locomotive to reach Tibet, being transported there by road vehicle and was used for the construction of the line. It has the standard 'watermelon' livery.
This model was a very limited release and was sold in a faux-leather presentation box, the first Bachmann China product to use foam inserts. It was available with a brass name plate on the bottom, made out to the owner of the model or simply just numbered. The model came with an assortment of optional add on details such as flags, banners and a big ribbon wreath for both ends. The locomotive itself has Chinese characters on the roof sides which basically translate as 'first locomotive in Tibet'. It also has some unique winterization grilles on the body sides. This model was the first DF4B to use the new improved (still press-fit) bogie sides. These bogie side frames were sold separately (oddly in pairs, rather than 4 packs) shortly afterwards to replace the old style on previous versions. It was also the first DF4B to have windscreen wipers as separate parts and had the side perspex side-window wind protectors as separate add on parts, rather than being added at the factory.
The forth release finally uses LED's for its lighting, although this is a bit of a mixed blessing. While using LED's eliminates the heating problems of the filament bulbs, they are unfortunately the wrong color (pale) blue and the main headlight is also quite dim.
Model Review - Fifth Series
Two locomotives of the fifth series of DF4B were released in May 2008, earlier than most of the scheduled 6th series, which followed some months after. These two locomotives were released fairly close to each other and, in my opinion, represent the ultimate DF4B's made to date. They were the last ones to feature the low profile wheels and still employed very heavy bullet-proof mechanism.
The first one was a passenger DF4B which was one of a handful in the Shanghai and Hangzhou areas to sport an advertising livery for Dahongying cigarettes, one of the premium brands made by the Ningbo Cigarette factory. The liveries were applied to these locomotives in the early 2000's and were repainted in the standard orange a few years later.
The second release was another special locomotive, painted in light blue under cream, in similar style to the 'Zhou Enlai' locomotive. This one was named "Worker Pioneer" and was principally a freight locomotive.
There are not too many detail upgrades to this model, the obvious one being the metal handrails are now single piece construction, rather than the rail and stantion type (which were a bit oversized in my eyes).
Model Review - Sixth Series
The latest flurry of DF4B diesels arrived mostly in 2008, with one exception - CD00216 in August 2009. Six new road numbers were made; one standard green/light blue 'watermelon', one green/yellow 'military' (limited edition), one green/light green, one green/light green (includes light green roof, fuel tank and bogies), a standard orange/yellow passenger livery and one white/blue/red livery of the local 'Jinwen Railway'. I believe the latter was a model commissioned by a railway club in China, but ended up on the mass market after poor sales - it was released quite some time after the others.
There was a major overhaul in the tooling of the mechanism of the locomotive, including wheel spacing and also with the bogie side frames again, while the shells themselves seem to have remained unscathed. The bogie side frames are now made of an awful type of plastic, that should not be bent, painted on or otherwise molested as they are very easily damaged. They are mounted via a single screw from the top. When released, there was a major uproar in the modelling community about the length of the bogies which resulted in a much wider gap between the fuel tank/pilots and the wheel sets. As such, Bachmann promptly made a large batch of replacement bogie side frames that were sent to the large retailers in Hong Kong and China to give away free with the new locomotives. The air hoses on the pilot were much finer with red painted handles and the uncoupling rods were also painted in two tone, but asides from this, details seem to be more or less the same.
The drive system has been totally reworked and although we're told this is somehow an 'improved' system, there are however two major areas which cause concern.
Problem number 1 - The weight has considerably dropped by at least a quarter from previous models. This may ease postage costs, but those who run heavy trains on gradients will really feel the difference.
Problem number 2 - The chassis itself is now made from a very soft alloy that deforms with the slightest amounts of pressure, a good example is by simply screwing the body shell back onto the frame! As a result, both my models from this run arrived witha bow in the frame. In the image below of the #7401 Jinwin Tielu DF4B (White/blue/red), you can see the bottom of the bent frame under the cab door on the left and compare this to the other side. This can be rectified by VERY gently bending it back by hand.
Problem number 3 - I The general build quality has dropped significantly. The wheelsets are now held are held in place by a very small plastic pin jutting out from the top of the bogie. If this pin snaps as one of mine did during transit (and another recent DF4B addition to my fleet), you will find the wheel set simply falls off the engine, disconnecting the drive shaft.
Problem number 4 - Bachmann has introduced deep wheel flanges to its models in an effort to 'improve' them.
Despite the above, the models still run very smoothly and quietly.
Model Review - Seventh Series
Not yet reviewed - coming soon.
Model Review - Eighth Series
A pair of decorated DF4B's were released in 2011. They are very similar to the sixth/seventh series.
The details on these are as we've come to expect. They both have the improved bogie with correct wheel width as the 6th series onwards, as well as the correct bogie sideframes. The paint work is very beautifully done on both - razor sharp, however on the orange variant, the special insignia tends to blend in a lot with the main color scheme. Seperate brass plates as Bachmann have done in the past for a number of their locomotives could have possibly solved this.
Model Review - Ninth Series
Not yet reviewed.
Model Review - Tenth Series
Bachmann China back from the dead?! Two new DF4B's released October 2021 - Details in Production summary, no review yet.
Photo above shows the warp issue with series 1 (right) against series 2 + (left). Note the different chassis style.
Photo above shows three of the four types of bogie side frame available; On top is the original press-fit type as standard on series 1, 2 & 3, the middle version is the improved press-fit type as standard on series 4 & 5 (also available as replacement part for series 1, 2 & 3), the bottom version is the new retooled screw-mount version for series 6. Not shown is a replacement version for series 6, which looks the same, but components are more spread out and are approximately 6mm longer. (Please note that this image was made up of six individual images and should therefore not be used to show side frame size differences with each other)
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