DG 760 - Photo P Anderson

Locomotive

Locomotive DG760

The building of DG760 was a ten year project which began in 1993. This page describes how I did it, the specifications of my DG760, some photos of various stages of building, and gives you a link to the original DG760 specifications on the TrainWeb website.

Choosing loco type

Being a motor mechanic by trade, I decided to build a diesel type of loco for the following reasons:

  • it required less work to be done on a lathe
  • most of the parts could be made using hand or electric hand tools
  • special parts could be acquired or made locally

Choosing the scale

I managed to acquire some simple drawings of a DX loco. My first task was to look at the scale sizes and scale them down to suitable sizes. I liked the philosophy of fellow club member Harold Sinclair, which was "make it big" because I wanted to use a small car motor, and because I didn't like the sound that lawn mower engines made. They needed high revs and always seemed to be overworked. After going around the wreckers yards and measuring the width of different motors, I soon found the width of the scale size of the DX engine bay was going to be too narrow.

I decided to look for a loco that utilized the full width of the body and found the DG loco picture on the front cover of the "Rails" Magazine. Then I found a black and white picture of a recabbed DG in the August 1978 "Rails" Magazine. Although some people were disappointed that I had chosen the recabbed version, I felt the original cab style version was plain and ordinary. In contrast, the recabbed version had a bit of character, and was painted in bright railway colours. There was only 10 of them built in this format, the first to be recabbed was DG 760.

My DG760 Specifications

DG760 was built using a second-hand Austin A40 1100cc A-series motor, which powers a Sperry-Vickers hydraulic pump, utilising Char-Lynn hydraulic traction motors. The traction motors are then chain-driven down to each bogie, which in turn powers all six axles. It has a 40 litre hydraulic tank and filter system. Wheels were turned from 210 mm x 35 mm steel slugs with axles of 35 mm diameter which were pressed and loctited on.

The braking system utilises a hydraulic master cylinder as a holding brake, and has vacuum-actuated main brakes which also powers the brakes for any carriages. The fuel system incorporates an electric fuel pump and utilises a plastic boat fuel tank which can be removed for safe refuelling. The electric system is a standard 12-volt system with a 70-amp alternator, with two halogen 50-watt headlights and 3 standard air horns. The cooling system is a fan-assisted radiator with an extra fan dragging in fresh air, and a secondary fan cooling an air cooler.

Photos of construction

Go to Flickr - DG760 to see photos of DG760 in various stages of being built.

Counting the cost

Building locos from scratch can be expensive, not to mention the countless hours spent in the workshop wondering whether or when you're ever going to get it finished. It was bit slow in the early years 1994 - 1998 when cost of machining was quite a major item. A real commitment was needed, and I eventually took the plunge and had the wheels, axles and bogie side frames specially made.

I was able to obtain quite a few parts at no cost and this helped to reduce the overall expense. At the end of January 2002, I decided I wanted to have it finished, so that I could take it to the 10th anniversary of Keirunga Park Live Steamers, in Havelock North, at Easter 2002. This was the loco's first major outing. The final cost was around $8,000 (that's what Dale thinks anyway!). To see DG760 in action at Keirunga, view my photo gallery.

Original DG760 Specifications

View a DG760 Fact Sheet on the TrainWeb website, giving original design details and specifications.