I know there has been discussion in the past here about fabricating steam locomotive cylinders vs. casting them.

The P2 Project in the UK (the same people who brought you Tornado) are well along on the construction of a new build P2 2-8-2, 3 cylinder, rotary valve, express passenger locomotive. They made the decision to fabricate the cylinders while using some castings for ports as opposed to fully casting them as they did with Tornado. Their latest update shows their progress.

https://www.p2steam.com/2021/12/25/cylinder-progress/

I'm not sure what the T1 Trust's plans are with their cylinders but this hybrid design is interesting.

Roger

Hello,

Don’t believe it’s stated in the article but looks like steel port castings obviously. Beautiful castings!…… and cast in steel makes them more interesting.

Assuming a good shot of stress relieving will be needed after all the welding.

Very good process for the T1 Trust to follow.

Thank you for posting!

Regards,

Randy

PRR had some M1 cast-iron cylinder and half-saddle sections replaced by a welded one-piece saddle and cylinder unit.

I believe the technology of that day gave the T1's cylinders that were cast with the engine frames.

Phil Mulligan

If you go to "Clear Track Ahead" on Youtube, at 20:10 you will see a T-1 Frame hanging from a crane at either Altoona or Baldwin; the integral cylinders are clearly visible; I think the Air Pump Brackets are also, ahead of the front cylinders.

This technology amazes me, but also scares me. With so many combined parts, a single machining mistake will ruin the entire casting. If you make a mistake drilling a hole, or tapping, or anything, can you fix it, or is the casting scrap?

It places an enormous responsibility on the machinists to get it correct 99.99% of the time.