Diagrams Index . Home
1:16.8 scale
D440, D441, D442
Driving wheels for the EAR (East African Railway) 4-8-2+2-8-4 class 59.

4′ 6″ diam., 14 oval spokes, humped inner rim.
Hub 14½″ face dia., 1.31″ out from the inner rim. Pin between at 14″. Tyre face 13/16″ below the inner rim.
If built as converted to run on Cape gauge the face of the tyre is 3/8″ above the inner rim.

Casting: 81.6 mm dia., 72.2 i/d., hub 2.0 mm out from the inner rim. Pin at 21.2 mm. Tyre face 1.2 mm below the inner rim.
If built as converted to run on Cape gauge the face of the tyre is 0.6 mm above the inner rim.

Narrow gauge loco set prices . Casting prices and stock

Scan of a casting in a set for an EAR 4-8-2+2-8-4 class 59,

Castings D440 Castings D441 Castings D442

D440 outer coupled wheel; D441, mid coupled wheel with thicker weight; D442, driven wheel.

Cross section diagram of castings D440-2
The diagram shows the earlier Gauge Three standard 8.0mm tyre width as an example.
The exact scale equivalent of this SAR/EAR 5″ wide tyre is 7.6mm at 1:16.8.
The current recommended Gauge 3 tyre width of 6.8mm would be under scale for this wheel.

The works drawings show that the wheels were designed to be capable of conversion or building to suit Cape Gauge by changing the position of the tyres on the wheel centres. The wheels suit 3′ 6″ gauge with the tyres in the normal position (above the inner rims), or, as built, with the tyres set back by 1 3/16″ on the wheel centres with the face of the tyre 13/16″ below the inner rim to reduce the back to back by 2 3/8″ for the EAR Metre gauge. I have allowed enough material on the castings for either version to be machined.

Link to Wikipedia page

Link to Bryn Morgan's SAR group:   https://www.facebook.com/groups/225873694237866/ https://www.facebook.com/groups/225873694237866/



Validated as HTML5

27 Mar 2013