DUAL MOTOR CONVERSION FOR THE HORNBY CLASS 59

To achieve the haulage capability of a Class 59 in model form, an additional motor bogie was fitted to the Hornby Railroad model to enhance the its tractive effort. As the experiment with the Class 66 above demonstrated, this conversion might not be necessary for short trains, but as a workbench exercise worked in alongside the wheel conversions, it was interesting to see how it would turn out.

The same technique will work for the Hornby Class 66 too. However, models intended for an MPD layout or small layouts may not need dual motor bogies. The bogies were fitted with wheels comprising of EM Gauge Society stepped axles and Black Beetle 14mm diameter disc wheels as described above.

Preparing the chassis frame

No changes were made to the existing motor bogie or its mount other than to ease the pivot a little. All of the changes took place at the trailing bogie end. An opening was cut to accommodate the second motor bogie measuring 60mm long and 28mm wide, leaving a lip of plastic on the inside of the frame to which the new bogie mount is built. The position of the opening was checked using the new motor bogie and marked in with a soft pencil.

The edges of the opening were drilled out using a 2mm drill and cut through with a modelling knife. It was trimmed back to the desired dimensions and cleaned up ready for the motor mount.

New bogie mount

A near copy of the existing bogie mount was built up out of 60-thou black styrene. The side pieces were cut 23mm wide and 14mm deep, topped off with a top piece measuring 23mm and 29mm in width. A 4.5mm diameter hole was drilled in the top to accept the motor pivot mount and the height of the frame on the bogie made up with shim washers. Assembly was undertaken with solvent cement and the joins reinforced with strips of

20-thou black styrene.

Finishing off

Once the model’s chassis was correctly balanced and level at each end, the bogies were wired together to a single Lenz decoder. Testing and running in followed with excellent results, especially after selecting the optimum motor configuration setting (CV50).

The change in performance was notable, with four driven axles providing more than enough traction for trains of 20 wagons. Whilst the first wheel conversion showed that a single motor bogie model could perform with up to 13 bogie wagons, it is at the limit of its capabilities and wear of gears and motor bogie frame will be increased as a result. Fitting an additional drive shares the load and reduces the risk of wear over time.

 Testing the converted Class 59/1 through staging yard track work.

 The dual motor bogie conversion is complete with ‘EM’ gauge wheels ready for testing on the main line!

The new mount is basically a copy of the old one composed of 60-thou black styrene and reinforced with strips of 20thou styrene.

↑ The opening is cleaned up to leave a ledge around the inside of the frame to which the new motor bogie mount is assembled. ↑

↑ One project was to fit an additional motor bogie to the latest Hornby Class 59/1 model, Hanson No. 59101. The same project can be done to both the Class 59/0 and Class 66 models to improve tractive effort.

↑ The project commences by measuring the position of the new motor bogie opening at the unpowered bogie end of the underframe. ↑