DF8B Class Diesel-electric Co-Co
The DF8B is a heavy freight locomotive designed on the earlier DF8. They have been produced since 1997 and over 1200 units have so far been produced as well as a number of variations. The V16 engine was upgraded to a whopping 4930hp and it is speed rated to 100kph. The main two producers of DF8B have been Qishuyan Locomotive Works and Ziyang Locomotive Works. With a few exceptions, the Ziyang locomotives (#0001 - 0***) have a very flat face compared to the Qishuyan models (#5001 - 57**) which are more rounded on the front of the roof and have the main headlight stick out of the roofline.
They have been very successful and have taken over much of the work from the older DF4B's, although in smaller numbers due to mass electrification of China's railways. DF8B's can be seen in every corner of the country.
CMR Line has produced ten versions of the DF8B. For the first time the flat cafe version has been produced as well and there are tooling differences in the roof, cab windows and builders plates as well. I have only purchased one CMR Line DF8B and went for the flat face version with the recessed headlight, typically seen on machines built at the Ziyang factory. Mine has a Qishuyan builders plate however, representing one of the very early DF8B's that came out of this factory before they upgraded to the more rounded design. CMR Line's DF8B's have an injected mold plastic body shell on an alloy frame. They measure 36mms wide54mms high 249mm long.
The outer box is a high quality two piece thick cardboard type. Thankfully CRM have moved away from the disastrous packaging from the ND4 class diesel models they produced a little earlier and this time the model is supported in a sleeved clear plastic clamshell. They have for some unknown reason kept the lower cradle portion of the old style packaging and the model is attached to that with four allen key bolts. The box also contains detail parts to be added by the owner and the instruction/schematic sheet.
CMR Line's DF8B's are a good representation of the class, but a bit sparse on details like something we would have seen 20 years ago on a Bachmann China model. They feature hollowed brass air horns, roof lifts, windshield wipers and wire handrails. Cab mirrors, brake pipe air hoses and traction booster arms are add on parts included in the box.
The paint work is not the best we've seen, and to be honest probably one of the worst I've come across since I started collecting Chinese models some 23 years ago (wow!). There is dark blue over spray into the thick cream strip down the entire length of the body and cream overspray into the blue around the headlight recesses and roof line (see photos below). CMR Line are much more capable of doing a good quality paint job so I'm not sure where they went wrong with this. The lettering is fairly sharp, but appears thinly applied. The builders plates are painted on.
The bogie details are quite good with good detail in the springs and shock absorbers. The cables hanging down look OK for a cast, but probably would have been nicer as an add on part. The roof details are not too bad and the air conditioner compressors look very nice with fan blade detail incorporated.
These are pretty hefty units at 585gms. The motor is strong and equipped with a pair of heavy brass flywheels on each end of the shaft to improve low speed performance. The motor is quiet, but there is a bit of a grumble coming from the gearboxes.
The DF8B is DCC ready and will accept any NMRA compatible 21 pin DCC decoder. The lights are very good with strong white (more cream) marker lights, cab light and main headlight - all of which are directional. Electricity for the motor and lights is excellent and taken from all wheels. CMR appear to be moving away from the copper brush system where a spring loaded brush rubs on the inner surface of the wheels and are now using a system where the axles rotate inside a thin copper plate which runs down the length of the bogies.
To access the circuit board, there are four main screws holding the shell to the frame which are hidden above the bogies between the second and third axles. The couplers must also be removed by removing the screw and sliding out before the shell will be free.
I have replaced the supplied knuckle couplers with genuine Kadee #156's (scale head, long shank, whiskers) as seen in the photos. By using the whisker couplers I have also used Kadee coupler boxes in place of CMR's spring loaded coupler boxes.