Stevers
Western Thunderer
OK, a like and a laugh will do, and note that this is as 'Western' as I've ever got!
Mixed media engineering with a vengeance. The original motor was probably for a mini-drill and cost £2.95, this is a brand new (also cheap) upgrade that made no obvious difference. I believe the flywheels are the Dynadrive ones in a cradle suspended on rubber pads. In the middle is a reduction Delrin chain drive down to the drive shaft for the bogies - the frame also mounted on rubber pads. A silicon(?) rubber tube works as well as anything to connect everything up.
This thing is so old that it was made in Hong Kong. Even with steel tyres, you can't have enough weight. Each wheel set has it's own scratch built gearbox, each with its own worm and the MRRC spur gears are used to gear up the final drive. Those gearboxes swivel on the worm axle to provide compensation. There's very little left of the Mainline bogies and then only round the edges. All done without glasses - and that does seem remarkable now. 10203 had the advantage of a mechanism needing only two 14:1 worms - much more efficient. These worms are likely to be 27:1 and Romfords.
The cardan shaft drive is to the inside end of the bogies, limiting it to curves not less than 3' 6" radius. Due to manufacturing intolerance, the cardan shafts are not exactly the same length and therefore not quite interchangeable. The UJ balls for the carden shaft end were from North West Short Lines then about the only people that supplied them. The pins have been replaced in steel and the sockets are home made after the originals split. The problem with four sets of worm gear is drag, and whilst it has a 90mph top speed, it does slow down a bit with twelve on, though I like to think that's more of a problem with the aged YMRG Gaugemaster controllers no longer having enough grunt. At speed it sounds like there's a lot going on in there - I'm told not unlike the real thing - and without a chip in sight!
If I ever felt the need to do this again I'd replicate the later 10203 design with 14:1 worm to the inside axle and delrin chain drive within the bogie though the smaller Warship wheels may not be quite large enough for that approach. Happily with the improvements in ready-to-run mechanisms, this sort of nonsense is no longer necessary - although I seem to remember that it was fun to do at the time!
Mixed media engineering with a vengeance. The original motor was probably for a mini-drill and cost £2.95, this is a brand new (also cheap) upgrade that made no obvious difference. I believe the flywheels are the Dynadrive ones in a cradle suspended on rubber pads. In the middle is a reduction Delrin chain drive down to the drive shaft for the bogies - the frame also mounted on rubber pads. A silicon(?) rubber tube works as well as anything to connect everything up.
This thing is so old that it was made in Hong Kong. Even with steel tyres, you can't have enough weight. Each wheel set has it's own scratch built gearbox, each with its own worm and the MRRC spur gears are used to gear up the final drive. Those gearboxes swivel on the worm axle to provide compensation. There's very little left of the Mainline bogies and then only round the edges. All done without glasses - and that does seem remarkable now. 10203 had the advantage of a mechanism needing only two 14:1 worms - much more efficient. These worms are likely to be 27:1 and Romfords.
The cardan shaft drive is to the inside end of the bogies, limiting it to curves not less than 3' 6" radius. Due to manufacturing intolerance, the cardan shafts are not exactly the same length and therefore not quite interchangeable. The UJ balls for the carden shaft end were from North West Short Lines then about the only people that supplied them. The pins have been replaced in steel and the sockets are home made after the originals split. The problem with four sets of worm gear is drag, and whilst it has a 90mph top speed, it does slow down a bit with twelve on, though I like to think that's more of a problem with the aged YMRG Gaugemaster controllers no longer having enough grunt. At speed it sounds like there's a lot going on in there - I'm told not unlike the real thing - and without a chip in sight!
If I ever felt the need to do this again I'd replicate the later 10203 design with 14:1 worm to the inside axle and delrin chain drive within the bogie though the smaller Warship wheels may not be quite large enough for that approach. Happily with the improvements in ready-to-run mechanisms, this sort of nonsense is no longer necessary - although I seem to remember that it was fun to do at the time!