A Transport Heritage New South Wales funded project.
One of the impediments to the regular operation of Variotram 2107 at Loftus is its hybrid ‘tram-train’ profile wheels are incompatible with the ‘old’ Sydney point work used at the museum.
The goods line that was used for the original Sydney Light Rail project was not converted to tramway standards – it was left compatible with heavy rail trains. At the time of the projects inception, grain was still being hauled into Pyrmont and the project planning proceeded on the basis that this would continue. So the trams were specified with ‘tram-train’ wheels that allowed the cars to negotiate heavy rail points in a safe manner.
This special wheel profile has a ‘step’ on the wheel back to engage the railway check rails. This gives a wheel with both tramway and railway ‘back-to-back’ measurements.
The old Sydney tramways used raised check rails on points – and the museum has many of these points recovered from locations around Sydney. These check-rails foul the ‘tram-train’ step on the back of the Variotram wheels.
This project, supported by Transport Heritage NSW, is to ‘in place’ mill the wheel backs to remove this step. This will make the wheels compatible with the museum tracks. To this end a Wollongong based specialist engineering firm Leussink Engineering has been engaged to perform this work. Leussink will design and fabricate the tools needed to perform the task and then their machinists will assemble the tool at Loftus and machine the wheels to a suitable profile.
Lifting 2107 to remove the bogies and send them for offsite work is not possible at Loftus at this time, as special ‘lifting bay’ will have to be constructed for the special Variotram jacks. In place wheel milling is the most cost effective method at this time.
One of the first tasks was define exactly what shape the wheels needed to be. Pictured is one of the ‘spare tires’ being measured to assist with creating a specification drawing,. This picture shows the back of a wheel and the ‘tram-train’ step that has to be machined off to make the wheels compatible with ‘old’ style Sydney tramway points.
Wednesday September 30, 2020
Leussink attended the museum and picked up one of the spare Variotram bogies to take back to their Unanderra works. They will use this bogie to assist with prototyping and testing the machine they need to create to do this work. This means when it comes to the wheels on 2107, they will have already used the machine on this bogie and the operators will have a tested process to follow.
Photos: Martin Pinches