Help us build the Front Bogie
The front bogie of a steam locomotive is a 4 wheel, unbraked truck. It's job is to carry the weight of the front of the locomotive and control the entry into and out of curves. The building of the bogie is the next stage of building Hengist after initial frame assembly is complete. In order to build the bogie, we will need to procure the following components.
The photo above shows the front bogie from 71000 Duke of Gloucester in a partially stripped condition. The central slide can be seen - the pipes are grease feeds from the grease nipples on the left side of the bogie stretcher. The axlebox guides and their manganese steel liners can be seen. The side check gear spring is just visible.
Click on the images below for a larger pictures.
|Bogie Stretcher Casting|
The bogie stretcher casting is the central 'skeleton' within the bogie upon which everything else is built. The 2 round areas are where the bogie bolsters engage; these carry the weight of the loco. The central area is where the centre slide is located.
The part will be cast in a foundry and then will be taken to a machining shop for machining - these are the grey areas on the drawing
Casting - £8,500
|2 wearing plates are required for the central slide to operate on - £82.50 each
4 bolts are required for the plates - £5.60 each
|Bogie Centre Slide|
|A pivot pin fastened to the underside of the locomotive frames engages with the central hole of the centre slide. The centre slide has the ability to move left and right on the stretcher casting but is restrained by centering springs. This ensures that when a locomotive enters a curve, the forces on the bogie wheel flanges are kept within limits. It also ensures that the loco is recentred after leaving a curve.
The slide is a casting which will require machining after casting.
Casting - £4,000
Machining - TBD
|Spring Cradle Plate|
|Under each of the "arms" of the stretcher sits a laminated spring of 21 leaves. This is upside down and the ends rest in a spring cradle. The ends of the spring cradle sit in a cup on top of the axleboxes. The cradle acts a compensation or equalising beam and helps to ensure that a wheel does not become unloaded. We need to purchase 4 arms to make up 2 pairs.
Cost - £860 per plate - 4 required
|To complete the cradle, we need :
4 off Spring Brackets @ £210 each - these are the 2 inner brackets you can see on the drawing. The ends of the spring rest here
4 off Distance Pieces @ £175 each - these are the 2 outer brackets supporting the dome headed pin
4 off Pivot Pins @ £91 each - this is the dome headed pin facing downwards that will rest in a cup on the top of the axle box
|Bogie Side Check gear|
|On the front and back of the bogie, there is the side check gear. This controls the movement of the bogie centre slide. For a full explanation of what is involved here, take a look at the bogie pages in the design section.|
|To complete the side gear, we need :
2 off Distance Pieces @ £82 each - the orange item. The inner ends of the spring rest here
4 off Spring Guides @ £187 each - the fawn item. The outer ends of the springs rest here
4 off Stops @ £52 each - the fawn item. These locate spring guide in the yellow beam arms
|Beams - Centre Slide to Side Check Gear|
|The Centre Slide must be restrained in movement by the Side Check Gear and the springs. 2 substantial beams connect the 2 components. The beams (yellow in the drawing) are fitted in slots in the centre slide. As the centre slide tries to move, it moves the beam which compresses 2 of the springs (one fore, one aft)
2 off Beams @ £275 each
|The pivot is bolted to the underside of the main frames into the Frame Stretcher for Bogie Pivot. This pivot then engages with the centre slide on the bogie.
Machining - £TBD
|Pivot Collar and Locking Ring|
|Once the pivot on the locomotive frames has been engaged with the centre slide of the bogie, a pivot collar and a locking ring are fitted underneath the centre slide to prevent the bogie from disengaging with the pivot. These are 2 components
Pivot Collar - £265
Locking Ring - £75
|2 bogie frames are bolted to each side of the central stretcher. At the moment, these are buried under other components. As soon as we can, we will update this page with a photo
2 off bogie frames - In Stock
Some machining work is required, costs £TBD
|Bogie Frame Stays|
|The front and rear of the frames are braced in position by 2 frame stays, 1 forward, 1 aft.
2 off bogie frame stays - In Stock
These require machining, costs £TBD
|8 axlebox guides are bolted to the bogie frames. These will allow the axleboxes to move vertically within the guides. Manganese Steel liners are bolted to the face of the guides and is the rubbing face for the axleboxes. Manganese steel is very hard wearing.
8 off axlebox guides - £3,100 (one pattern, 4 castings)
8 off manganese steel liners @ £100 each
|2 axles are required. The axle is a safety critical component and must be supplied by accredited suppliers.
2 off axles @ £10,000 each
|The bogie has 4 wheels and these have now been cast. The photo shows the wheels being heat treated after excess metal has been removed from the casting.
Each wheel will require a tyre, another safety critical component.
4 off wheels - Manufacturing in Progress. Sponsored by Member
4 off Tyres - £ TBD
The wheels will require machining and the tyres will need fitting to the wheels - costs £TBD
|Axle Cannon Boxes|
|The cannon box is a single piece casting which comprises of 2 axle boxes at each end of the cannon box and a tube fixed to the axleboxes which rigidly holds the axleboxes in position. It is split horizontally to allow it to be assembled. The cannon box bearing was introduced by George Stephenson on the Locomotion. Because the driving axle was now enclosed, this provided the necessity for coupling rods to be developed. A set of taper roller bearings is fitted to each axlebox and the cannon box fixes the alignment of these bearings to each other. These will be expensive to produce as they are a critical component. The drawing shows half of a cannon box.
We are currently working tpo produce a CAD model for this component. This will be checked by Timken.
2 off axle cannon boxes - £ TBD