Just got an email from the PRR T1 Guys that they are finishing engineering on Frame and are getting ready to start construction this Fall. This has been the piece for me that will put this project over the hump. Sounds like they hired FMW Solutions to do the final engineering to make it in weldable sections.

I am planning on attending their talk at the PRR Convention in Harrisburg next month. I will report back what they have to say.

Here is their announcement https://prrt1steamlocomotivetrust.org/frame-club/

Ted

Agree, especially since the frame includes the cylinders etc, it's probably the single most challenging piece to build.

Will be quite something to see the frame come together.

It's my understanding the first 52 T1 frames were castings while the new one (#53) will be a weldment.

Phil Mulligan

Yes that’s what I’ve read too. I’m curious what prevents the new one from being cast like the originals.

Most likely the fact that there’s no where in the States to do castings that large. That and weldments are very easy to engineer using specified welding procedures. Plus casting is not as strong as proper weldments. Plus pound for pound (which is the name of the game here) weldments will always win.

I believe their whole mission is to redesign the locomotive to work the kinks out and make it go to its fullest potential.

I have a hard time believing this will actually happen like the stories the group has told us all these years. But hey. I wish them luck. Prove me wrong. I’d love to see it. I just don’t have the expendable income to donate to something that I think is a very far fetched dream. But we shall see crazier things have happened.

I'd guess in the 75+ years since the first 52 T1's were built, technology has changed. Weldments that big can now be destressed while I don't know if there is a foundry that can make such a casting.

Interesting side story. USN bought Alco engines for Fleet Tugs (ATO) and Ocean Minesweepers (MSO) during WWII (plus one submarine). However the Navy did not like the cast engine bed or block of the 538T and 539T. Alco redesigned the engines with weldments in 1940 so the Navy ships got the 540T model. That had to do with the flexing a ship had to do in a heavy sea; clearly the sailors had not seen some of the tracks S-2's had to navigate. Except for the sub, which was an experimental, the Alcos went to ships that pulled things. A single ATO could tow a damaged heavy cruiser at about 3 knots. Without the heavy cruiser she could make 14-16 knots.

Phil Mulligan

There was some discussion on the frame building in one of the earlier T1 Project threads here, some of it may be worth the read (starting about page 5 or so)
viewtopic.php?f=1&t=40050&hilit=Frame+weldment&start=60

The T1 Trust's General Manager was kind enough to explain the frame construction decision in a previous thread.

viewtopic.php?f=1&t=43986&start=30

I remember reading the T1 Trust answering this in the FB comments about a year or so ago when asked; so I dug up the post. Basically cost.

https://www.facebook.com/t1locomotive/p ... 571448065/

The frame issue basically boils down to GSC being no longer in the business of making cast engine beds. It would be interesting to re-create much of the 'lore' and wisdom involved in making the cast beds... but actually implementing that knowledge to get everything to come out 'right' and to precise dimensions with the first pour... not so likely.
Best technology remains lost-foam castings for the complicated work, like the steam passages and pedestals, with full-penetration welding on what I expect will be a rotatable jig (like the frame Bulleid used for the Leader frames, on steroids...)

I learned laser keyhole welding to have some insight into the right techniques to do a fabricated frame like this. It was and is my opinion that the job should be done entirely in controlled atmosphere. I'm not expecting any showstopping surprises... it's an understood situation.

Nowhere large enough to pour this?

Heck, dig a hole in the ground and pack sand into and draw your pattern! There are still foundries out there that bury patterns into the ground and pour them directly.

I agree it comes down to cost. That is a long pour but it can be done.

Thanks. Makes sense.

My comments from above still hold true except the price has gone up. There is another major advantage to building the frame in smaller sections and welding together, machining.

We can now machine pedestals, cylinders, poppet valves, etc in smaller machines prior to welding. If we cast it or just welded everything together first, then we would have to find huge machines to machine each section or use portable machines. Some things like cylinders will be bored close with the final boring being completed at time of tramming once all frame in assembled/welded and heat treated.

We will have a welding plan to control shrink to allow best fit to reduce movement of sections during assembly/weld. This is a very important piece of the engineering so that we can machine prior to welding.

We have been working on this plan for several years and feel quite confident on it. Once the final engineering is completed and all stress analysis is complete, we will produce final shop drawings and go to bid. We have narrowed the frame construction to two AAR shops.

Engineering for the frame cost us around $140,000 which we are very close to having that all funded and we have already started raising funds for the construction. We have had several generous donors contribute to the construction fund so we have a nice start on that. Raising funds will continue in earnest over next year to get frame completed.

Jason

Hello,

It’s a shame one if the most intricate and interesting parts of this locomotive will ultimately be hidden from view once assembled. It would be cool if the Trust would have a “GSC esque” photo shoot of the frame when fabrication is complete. This may generate some serious enthusiasm.

Who says machinery cannot be an art?

VERY interesting……

Regards,

Randy Musselman

Haven't seen this video here yet, this is WMSR #1309 equipped with #5550's whistle at the end of June, very nice sound. Is this the first part of the T1 actually put in service? https://fb.watch/e8vVyDw5cQ/

Here was a stationary test: https://fb.watch/e8w1xkHemc/