Tuesday, 22 January 2019

D/DA Class Diesel

DA (left) and D Class Test Models

First Test Print of D Class
Marbelup Models has finished the 3D design for a WAGR/Westrail D class diesel.  Test prints of all the 3D-printed parts have now arrived, and the test model has been assembled complete with Hollywood Foundry mechanism. The 3D design took approx 80 hours.

Thanks to Gav and Rob for helping out with photos and other prototype information.

The 3D design for the DA has also been completed.  The DA doesn't have dynamic brakes, so the short hood is fairly plain and also slightly lower.  The fuel tank is also shorter.  Test prints for the DA arrived on 19 December.

First Test Print of DA Class

Fuel Tanks - DA (left) and D (right)
D Fuel Tank with 7 layers of lead sheet installed.  166 grams in total.
Top 2 layers have a gap in the centre to clear the motor.
Test prints of D Class underframe and fuel tank
"Shop" bogies are dummies originally made for RA.  "Motor" is also a dummy.
The present models represents the D and DA class from delivery in 1971/1972 until the Westrail era.  In the late Westrail era (late 1990's), some of the DA locos were rebuilt into DAZ class.  Visible alterations included different cab windows, changes to various grilles on the body, and different brake cylinders on the bogies (on some locos).  Marbelup Models plans to produce a DAZ version as well.

Bogie Rendering
The D class uses a custom made drive mechanism from Hollywood Foundry.  Hollywood Foundry don't have the correct size wheels (15.7 mm) in their normal range, but the wheels are available from Northyard in New Zealand.  The minimum operating radius is 600 mm.

For DCC sound, the underframe includes mounting for a speaker.  The specific engine sound -EMD 645 Non-Turbo - is available in the Tsunami range of sound decoders from Soundtraxx.