Imaginary Locomotives

[Suzie]

I give you the class 75, a modified class 71 with 750V DC retained on 3rd rail only, but now with 1500V DC (using both pantographs) and 25KV AC (only requiring one pantograph) with the transformer, rectifier and extra switching housed in the extended body.

 

Edited October 27, 2017 by Suzie

[John M Upton]

Bumping this topic!

 

The 20 pulling pacers could come true soon, but towing them to the scrapyard.

 

I'm not so sure.  I have this nasty feeling that the DfT may well plead poverty, reverse its ruling that they have to go and find further use for them elsewhere....

[DavidB-AU]

I'm not so sure.  I have this nasty feeling that the DfT may well plead poverty, reverse its ruling that they have to go and find further use for them elsewhere....

Anybody got Iran's phone number?

 

Cheers

David

[scots region]

I give you the class 75, a modified class 71 with 750V DC retained on 3rd rail only, but now with 1500V DC (using both pantographs) and 25KV AC (only requiring one pantograph) with the transformer, rectifier and extra switching housed in the extended body.

 

class-75.jpg

Now where did I park my Tardis?

[john new]

Ah forgive my ignorance. Electric locos are fascinating to me. 

 

For any one interested in pioneer electrics (and those running on odd voltages) there will be a new SLS book launching at Warley bringing together several articles into one volume. Some of the one's that were built look like they should have stayed imaginary!

Edited October 28, 2017 by john new

[Budgie]

Following on from Suzie's idea of a 4-unit electric loco in the form of the Milwaukee Road's EF5, and the discussion of electricity transmission at various voltages, I naturally started thinking about eliminating the electrical problems by doing the same sort of thing with a diesel locomotive. Not a 4-unit loco like the EF5, but a 3-unit loco, like the EF3, but built starting with the Crompton as a basis. Of course, it would be class 33/3, numbered 33333. Any takers?

[Suzie]

Here is BRCWs offering to compete with Kestrel when a 4000HP loco for hauling heavy stone from Meldon quarry on the Southern was requested. Who needs one of those funny new-fangled class 59 shed thingies.

 

 

Not yet received its TOPS number, hence the pre-TOPS D7333

Edited October 29, 2017 by Suzie

[Suzie]

I think it looks better with a shorter 'B' unit. Room inside for the fuel tank:-

 

[Budgie]

I could quite fancy making a model of that. Start with 4 second-hand Lima class 33s and a razor saw ...

[Satan's Goldfish]

... may I introduce you to post 592: http://www.rmweb.co.uk/community/index.php?/topic/14790-imaginary-locomotives/?p=2241880 similar concept, fraction less length (only 3 lima victims required)

[Corbs]

I could quite fancy making a model of that. Start with 4 second-hand Lima class 33s and a razor saw ...

[DavidB-AU]

Speaking of B units...

 

 

Cheers

David

[scots region]

Speaking of B units...20B.jpgCheersDavid

I am wondering just how hard it would be to pull off a twin-cab ‘chopper’. I’m just worried I’d have to go cutting something up near the worm screw.

[Budgie]

... may I introduce you to post 592: http://www.rmweb.co.uk/community/index.php?/topic/14790-imaginary-locomotives/?p=2241880 similar concept, fraction less length (only 3 lima victims required)

I'm not so sure about that. With only 4 bogies instead of 6, wouldn't it have a lot less power?

[Wolseley]

While I was looking for something else, I came across a picture of a model of an NSWGR AC38.  Looks rather like the illegitimate offspring of an AD60 and a C38.  Apparently there was a proposal (probably not a very serious one though) to build such a machine before the C38 was designed and built.  An intriguing machine, but not particularly attractive.  It has a fairly strong resemblance to a Garratt that was built for the Algerian railways.

 

[Satan's Goldfish]

I'm not so sure about that. With only 4 bogies instead of 6, wouldn't it have a lot less power?

Good point. Depends whether a 33s power is limited by its engine or its traction motors i imagine. If the traction motors on a normal 33 are already at 100% then yes power would be less. If they can take more power than the engine can provide then the 3 engine power output driving 8 traction motors could be the same as if they were powering 12.

 

Bigger problem I've noticed looking back at these would be axle weight. They might benefit from pony trucks in the middle to help support the centre unit weight, bo-bo1-1bo-bo. Or taking traction motors into account, bo-co-co-bo.

[DavidB-AU]

While I was looking for something else, I came across a picture of a model of an NSWGR AC38.  Looks rather like the illegitimate offspring of an AD60 and a C38.  Apparently there was a proposal (probably not a very serious one though) to build such a machine before the C38 was designed and built.  An intriguing machine, but not particularly attractive.  It has a fairly strong resemblance to a Garratt that was built for the Algerian railways.

It was directly based on the Algerian BT. If you look at the cab windows it was to have dual controls.

 

Cheers

David

[russ p]

Speaking of B units...20B.jpgCheersDavid

You don't realise how close you are to reality here, this VERY nearly happened in the early days of DRS

[DavidB-AU]

This is different from the previous one. Who can work out what this might be?

 

 

Cheers

David

[russ p]

A slug as there is no cooler group, that wasn't on the plan!

[Satan's Goldfish]

Would a slug with a cab not be more useful in the class 20 family? Can Still run nose to nose for travelling in either direction, but only 1 engine driving all 8 axles....slowly...

[Budgie]

Good point. Depends whether a 33s power is limited by its engine or its traction motors i imagine. If the traction motors on a normal 33 are already at 100% then yes power would be less. If they can take more power than the engine can provide then the 3 engine power output driving 8 traction motors could be the same as if they were powering 12.

 

Bigger problem I've noticed looking back at these would be axle weight. They might benefit from pony trucks in the middle to help support the centre unit weight, bo-bo1-1bo-bo. Or taking traction motors into account, bo-co-co-bo.

Other problems: if something goes wrong with just one part of the articulated combo, the whole shebang has to be taken out of use while it is fixed; with separate units, just the unit that has the fault needs taking out of use.

[BernardTPM]

I'm not so sure about that. With only 4 bogies instead of 6, wouldn't it have a lot less power?

I think you're mixing up power and tractive effort. If you have the same diesel engines installed then the power is identical. There's also adhesion to consider when it comes to the amount of power you can actually put down. While there are fewer axles to spread the load on the articulated version there's some weight saving by having fewer bogies and a higher axle load might actually be beneficial if it's within weight limits. To really work out the potential effectivelness of the design you'd have to do quite a bit of work.

[Suzie]

The 33 is route availability 6, so since an articulated set would most likely be used on heavier routes upping the axle load by 25% to around 25 tons could probably be managed and still stay in route availability 8. You will be losing the weight of four cabs and two bogies, so if that adds up to 40 tons you are getting there. The weight on the outer units would need to be concentrated at the cab ends - not sure what is heavier, engine or alternator/dynamo, but I guess the coolers will be lighter.

[Suzie]

Not sure what is in the noses of the class 37, but they start as route availability 5 so might work better to produce an articulated set with a low RA being on 12 axles when the inner cabs are removed.