I’m familiar with 3MT 82045 as I often see them fundraising on the SVR, and everyone knows about Tornado, but I had no idea there were over 20 brand new steam locomotives currently being built.
http://newbuildsteam.com/what-is-new-build-steam/

A couple of impressive videos of big lumps of steel being cast or bent.

[video]https://www.youtube.com/watch?v=SNuQwtb6-jw[/video]

[video]https://www.youtube.com/watch?v=LnFm4Q5uyZU[/video]

Im more interested in the proposal to build a new replica of one the LMS “Twins” 10000 / 10001.
http://www.lms10000.org/home
These really are genesis for UK mainline diesels and were sadly scrapped before diesel preservation had taken off in the UK.
There is nothing representative that survived from that era in early diesels in the uk, other than some shunters, so these really would be important than another derivative of another GWR engine.

I’m sure that there’s a few Warship and Hymek diesels kicking around.

Those are both from 10 years after nationalisation.
It would certainly be significant to see a new LMS main line diesel built, but only from an enthusiast’s point of view.
Most people who visit a heritage railway want to see steam trains and I reckon a 3MT is a good choice for the distances, speeds and weights involved.

CountZero, there are two warships and I think 4 hymeks preserved. They aren’t first generation mainline diesels though.

I think its the North Somerset Railway (? – the one that runs to Minehead) that have at least 1 Hymek, Warship and a Western restored. Three of my favourite engines right there. Should have planned my visit there earlier this year a bit better as we started at one end and just sat on the train to Minehead and back and passed the station halfway where the diesels are stabled…

If anyones interested though, its a great line – best preserved railway I’ve been on so far.

There are quite a few books out about building new steam locos, Haynes one is quite good about tornado, have a look at the picture of all the electronics under the drivers seat, all required by network rail for mainline running.

With the advent of CNC maching, and computer aided design programes, re building or copying old machines is a lot easier, its just the tradesmens skills that have been lost, along with the various patterns and jigs used in their construction.

and the problem with making a real life like diesel loco is getting an engine, and control gear, a hugely expensive task, where as steamers are just basiclly metal bashed, welded soldered or riveted with a lot of bolts and nuts for added manliness.

The LNER P2 in that list is most interesting to me, it’d be great to see.

There’s quite a lot of people trying to build new versions of extinct diesels too, like the Baby Deltic which I believe someone found an engine for which is destined to go in a butchered Class 37 shell to look like the real thing.

there’s a few Warship and Hymek diesels

There’s one runs past my garden regularly. Not a patch on the Deltic.

And neither can hold a candle to Tornado. The nice folks who banged Tornado into shape are proposing a new Gresley P2

P2

Should be good.