Tuesday, 22 January 2019

WOB Iron Ore Wagon

WOB Iron Ore Wagon (Standard Gauge, HO Scale)

The 25 WOB iron ore wagons entered service in 1974.  WAGR obtained the wagons, which were brand new and built by Comeng for Mt Newman Mining Company (now BHP Iron Ore) to replace a number of the existing WO and WOA wagons which were damaged in derailments.  As built, the wagons were considerably higher and were cut down at Midland Workshops to be compatible with the other WAGR standard gauge iron ore wagons. For more information on the prototype, refer to the WA Wagon Pages.

This WAGR publicity photo shows the entire fleet of 25 WOB's when brand new.  The photo is on display at the Rail Heritage WA museum but not available on their web site.
The WOB's were originally used to carry iron ore from Koolyanobbing to Kwinana, this iron ore traffic being the principal economic justification for the WAGR standard gauge rail project of the late 1960's.  Most, if not all, of the WOB's are still in service but the iron ore from Koolyanobbing is now railed to Esperance and exported from there.

One of many photos of WOB's at pilbararailways.com.au
In 1977/8, fifteen of the wagons were converted to WSM ballast hoppers which involved fitting bottom discharge doors, internal slope sheets and welding on part of the tops which had been previously cut off.  Approx. 20 years later, the ones converted to ballast hoppers were converted back to iron ore wagons, although the converted wagons retain some remnants of the bottom discharge doors and have a different arrangement of air brake cylinders compared to the 10 unconverted wagons.  The model depicts the unconverted version.  

The Marbelup Models WOB wagon consists of a 1-piece 3D-printed body.  To complete the model, the purchaser must add bogies, couplers, and some small detail items.  The model is designed to accommodate Kadee HO whisker couplers (in #262 draft gear boxes) but one end can also be fitted with a rotary coupler, as per the prototype, to allow the possibility of unloading using a rotary car dumper (tippler).  HO scale rotary couplers are made by Glatzl and are available from Sergent Engineering in the USA, together with matching dummy couplers.

The bogies shown in the model photos are from Kadee, part number #569.  These bogies are made from a high-density plastic and weigh almost as much as metal bogies, thus adding some weight to the wagon.  Kadee also offer #1569 bogies which are identical apart from being fitted with finer Code 88 wheelsets.

The following is a list of parts required to complete the WOB wagon:
  • 1 pair Kadee #569 or #1569 bogies
  • 2 x Kadee Whisker couplers e.g. #148 (standard head) or #158 (scale head)
  • 2 x Kadee #262 draft gear boxes (20 per pack)
  • 2 x Detail Associates #6206 air hoses (6 per pack)
  • 1 x Handbrake wheel - e.g. Model etch ME7 or ME47
  • Handrail and uncoupling lever - formed from 0.4 mm brass wire
  • Paint and decals
  • Fixing screws for couplers and bogies e.g. 2-56.
For rotary coupler operation, the following parts are needed instead of the Kadee couplers listed above:
  • 1 x Glatzl rotary coupler GLTZR (available in packs of 3 from Sergent Engineering)
  • 1 x Glatzl dummy (economy) coupler GLTZ ((available in packs of 3 from Sergent Engineering)
  • 1 x Kadee #262 draft gear box