Ground Level Passenger Car Bogies
Pictured below are photographs of the 3 types of passenger car bogies we use at Malden, all are vacuum braked, hopefully the description by each photograph will let the viewer understand the differences. We are now experimenting with a plastic vacuum cylinder as used by Firmley ME club, more information to follow on progress in due course.
Original vacuum braked bogie, with centre mounted brake cylinder under bogie pin.
VERSION 1. BOGIE
Problems brakes get stuck, poor brake force
50% of vehicles fitted with this system
Click picture to enlarge
Original vacuum braked bogie, with centre mounted brake cylinder under bogie pin.
VERSION 1. BOGIE
Problems brakes get stuck, poor brake force
50% of vehicles fitted with this system
Click picture to enlarge
Original vacuum braked bogie, with centre mounted brake cylinder under bogie pin.
VERSION 1. BOGIE
Problems brakes get stuck, poor brake force
50% of vehicles fitted with this system
Click picture to enlarge
Original vacuum braked bogie, with centre mounted brake cylinder under bogie pin.
VERSION 1. BOGIE
Problems brakes get stuck, poor brake force
50% of vehicles fitted with this system
Click picture to enlarge
Modified vacuum braked bogie, with end mounted brake cylinder at end of bogie.
VERSION 2. BOGIE
Attempt to overcome Version 1 problems.
50% of vehicles fitted with this system
Click picture to enlarge
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Modified vacuum braked bogie, with end mounted brake cylinder at end of bogie.
VERSION 2. BOGIE
Attempt to overcome Version 1 problems.
50% of vehicles fitted with this system
Click picture to enlarge
Modified vacuum braked bogie, with end mounted brake cylinder at end of bogie.
VERSION 2. BOGIE
Attempt to overcome Version 1 problems.
50% of vehicles fitted with this system
Click picture to enlarge
Comparison of version 1 and version 2 braked bogies
VERSION 1 BOGIE - Left hand end
VERSION 2 BOGIE - Right hand end
50% of vehicles fitted with each system
Click picture to enlarge
Heavy Duty braked bogie for use with external brake cylinder, with brake shoes operated by bowden cable.
VERSION 3. BOGIE
These are only fitted to our steel bodied vehicles, like tool truck, 'Goliath; signal trucks and disabled passenger coach.
Click any of the following picture to enlarge.
Heavy duty bogies are based on the same frame and wheelset as the standard bogie, but have revised springing arrangements, races specified for heavy loads and a strengthened bolster plate. With heaviest springing a bogie is rated for a maximum load of 450Kg. It supports the required rate of twist between bogies for vehicles with up to 3.5m bogie centres.
One brake stretcher has its central pin drilled 3mm out of centre and the other 1.5mm out of centre. Hence by rotating the two stretchers variously by 180 degrees you can achieve 9mm of adjustment for brake wear.
There are only two bolts to secure the entire unit to the bogie frame making it very easy to service. All other joints are split pinned. The pins for attaching the stretchers to the brake blocks are made by turning the ends of the stretcher in a 4 jaw chuck.
Brake mechanism leverage is such that a maximum 10kg pull on the Bowden cable is required. Hence cheaply available bicycle cables can be used. To minimise losses through bending, the stretchers and actuators are made from 25x12mm bar although it is still possible to for these to bend under the pressure applied.
Heavy Duty braked bogie for use with external brake cylinder, with brake shoes operated by bowden cable.
Click picture to enlarge