Converting MK3s - Really Worth it?

[rebmcr]

Was something of an error by BREL not to have power doors and retention tanks from new.

The HST project specifically did not use 'new' technologies like that, in order to properly differentiate from the APT.

 

[Bletchleyite]

The HST project specifically did not use 'new' technologies like that, in order to properly differentiate from the APT.

Power doors weren't new technology - they had been used on the PEP EMUs prior to that, and some Mk1 EMUs too.

Plug doors would have been, but they could have used traditional air-powered sliding doors.

Of course what they really should have done was persisted with the UIC door on the XP64 stock - that would have saved many lives.

 

[hexagon789]

Power doors weren't new technology - they had been used on the PEP EMUs prior to that, and some Mk1 EMUs too.

Plug doors would have been, but they could have used traditional air-powered sliding doors.

Of course what they really should have done was persisted with the UIC door on the XP64 stock - that would have saved many lives.

Plug doors and retention toilets were both available and considered at the time of the production HST construction.

 

[pt_mad]

How much more complex is a plug or electric sliding door compared to say the air doors previously used in buses?

 

[edwin_m]

Air powered sliding doors had been in use on the Underground and Merseyrail since before WW2 and on the Shenfield suburban units not long after. The adoption of air brakes could have facilitated their use on the Mk3, but would have prevented mixing and matching Mk3s with older stock - which in the event didn't happen much apart from the Mk1 buffets and brakes that could have been fitted with the wiring for door control when they were converted to air brake. I don't think electric doors came in until much more recently.

 

[43096]

Air powered sliding doors had been in use on the Underground and Merseyrail since before WW2 and on the Shenfield suburban units not long after. The adoption of air brakes could have facilitated their use on the Mk3, but would have prevented mixing and matching Mk3s with older stock - which in the event didn't happen much apart from the Mk1 buffets and brakes that could have been fitted with the wiring for door control when they were converted to air brake. I don't think electric doors came in until much more recently.

Mark 3s worked regularly with Mark 2s on West Coast for many years, which is rather different to what you describe. It was only the advent of 110mph running that saw all Mark 3 sets formed up, and of course West Coast “Mark 2” sets had Mark 3 buffets right up to the end.

 

[w1bbl3]

How much more complex is a plug or electric sliding door compared to say the air doors previously used in buses?

It's less complex that's the advantage of electromechanical door systems.

Generally pneumatic doors are the lowest initial cost as the components required are inexpensive, however you need more of them and they need maintaining more often this includes maintenance on the air regulator and compressor together with pressure testing the lines. Next up come electric-pneumatic these give you most of the cost advantages of pneumatic but with a lower maintenance cost and higher reliability associated with electric. Finally full electromechanical, high cost but actually low complexity, low maintenance and high reliability.

 

[edwin_m]

Mark 3s worked regularly with Mark 2s on West Coast for many years, which is rather different to what you describe. It was only the advent of 110mph running that saw all Mark 3 sets formed up, and of course West Coast “Mark 2” sets had Mark 3 buffets right up to the end.

My recollection is that originally most of the WCML sets were Mk3 with Mk1 brake and buffet, some mainly on West Midlands workings having Mk2 instead of Mk3. I think the only significant Mk2/Mk3 mixing was on the push-pulls in Scotland. All the sets including the Mk2s got Mk3 DVTs and buffets later on.

 

[43096]

My recollection is that originally most of the WCML sets were Mk3 with Mk1 brake and buffet, some mainly on West Midlands workings having Mk2 instead of Mk3. I think the only significant Mk2/Mk3 mixing was on the push-pulls in Scotland. All the sets including the Mk2s got Mk3 DVTs and buffets later on.

Depends how far back your recollection goes, doesn’t it?

 

[physics34]

The problem is more about how efficient the project has been rather than is it worth converting them.

Although im not knowledgeable about how much work they need regarding corrosion etc, youd expect it a good idea and cheaper idea to do these conversation instead of ordering new stock.

Clearly if the completion dates have been delayed then that is probably poor project management

 

[Cowley]

My recollection is that originally most of the WCML sets were Mk3 with Mk1 brake and buffet, some mainly on West Midlands workings having Mk2 instead of Mk3. I think the only significant Mk2/Mk3 mixing was on the push-pulls in Scotland. All the sets including the Mk2s got Mk3 DVTs and buffets later on.

Edwin - There’s a handy recent thread here about the subject:

https://www.railforums.co.uk/threads/did-mk2s-mk3s-ever-run-together.184315/