Huh??? Completely obsolete? Nearly every engine in the World big or small is poured in a foundry no matter how complex it is. They poured locomotive frames in a foundry because it was fast, cheap, and durable. Welding anything is extremely slow and expensive. It's not like they didn't have arc welding in the steam locomotive days. If they could have made frames faster, cheaper, or more durable than cast steel then they would have done it.

If they were mass producing steam locomotives again I am certain they would mass produce cast steel frames in a foundry. You other option would be to mill extremely large and thick billets of steel (likely at least 5 inches thick) and weld them together. Or to weld a bunch of plates together to get the thickness. In either case it is going to take likely a month or longer just to get a single frame with a lot of expense.

People also talk about this frame like it is impossible to find a foundry big enough to pour it. There is probably a hundred foundries that can pour that frame. The machinery used in steel mills is massive in size. The majority of that machinery is made from cast iron. When I worked in the marine industry there was engines large enough you could actually walk through them. All poured in a mold in a foundry. Here is a video of a very large marine engine being poured https://www.youtube.com/watch?v=w4uMX5mWAF4

This 80,000 ton hydraulic press in China has many large castings https://imgur.com/NblCszN

https://www.abc.net.au/news/2017-07-09/ ... ll/8691104

Obviously with the T1 project they have nothing but time on their hands. They can certainly use a frame with welded plates which will be as good as a cast steel frame. But I won't be surprised if it takes all year to make it and likely cost twice as much as if they paid a foundry to do cast it.

PRR was fabricating cylinder blocks in the 1930's despite owning a rather capable foundry.

EMD cylinder blocks are fabricated weldments, not castings.

I don't know where you have been for the past half century but nobody, and I mean nobody in their right mind specifies large castings anymore if they can help it. Just about all large industrial equipment with section thickness up to about 6" will design and fabricate out of steel plate.

Contrary to your belief, weldments are quickly made with a minimal amount of equipment. With a design in hand, burning table, welding stations and a heat treat oven any complex item can be created that equals or exceeds the strength of a steel casting and possibly with a significant weight savings.

To create a large steel casting requires a design that takes into account shrinkage characteristics, avoidance of large to small section transitions, use of T sections instead of X sections, solidification modeling etc. Then the decision must be made to either have a wooden pattern made or to create a lost foam pattern and then find a suitable foundry willing to cast the part. Remember this is a one shot deal. If that mold runs out you start from scratch again and flush all that money down the drain. Screw up a weldment and you cut out the offending piece and weld in the right piece.

On top of that, large casting design technological advancement pretty much ceased decades ago but weldment technology continues to be improved.

As for speed. Send your CAD design to ANY of MULTIPLE heavy weldment shops out there and you will have your part a few weeks later.

Want a big casting? It will take you weeks just to find the right foundry to do the job.

And what are my qualifications? Nothing much. Just been on casting teams that regularly poured 50 to 100 ton castings.

Well said Rick. Any good welding shop (Read - A SHIPYARD), can likely knock one of these out in just a few weeks. The yard I used to deal with often has a CNC Plasma table that takes up an entire large building, and can knock these things out in no time.

Here's a discussion on that:

https://youtu.be/ERNezIjd-GE?t=2930

Absolutes and exceptions, blah blah blah…

Whether a casting or a fabrication is better is similar to the argument of which of the big three makes a better pickup truck.

In the end it's not which has the best features, but more importantly, which faults can you live with.

In contrast to the welded blocks:

https://youtu.be/w4uMX5mWAF4

Some good discussion here.

We have already contacted 2 different foundries and sent them drawings of our frame to cast complete. One came back as a no bid and the other one wanted a minimum of 3 pours to get it right. The patterns and 3 pours would cost us $2.5 million. The company was more than capable, but felt it would take at least 2 pours to get all the gating right.

From above "if mass producing today they would cast frames" the truth is this is a one off. As Kelly showed, the PRR fabricated cylinders many times and even converted a K4 to poppet valves with welded cylinders. We have copies of those drawings and our engineers as using them to convert frame to weldments and some smaller more manageable castings.

This is the path we are headed down after boiler is mostly complete (minus tubes/flues)

We will be releasing frame drawings once we have completed conversion and finite stress analyses. Look for more details on this at the PRRT&HS convention in May.

2020 will be an exciting year as much work will all start coming together. If you like the project, find your way to the website and make a donation. Every dollar gets us closer to running.

Jason Johnson
General Manager
PRR T1 Trust
www.t1trust.org

You guys aren't the only ones being steered away from castings, it seems like. This is the rear truck on some new EMD locomotive. All welded construction. Looks WAY less massive than it's cast counterparts, and I'd bet completely machine made... cut, assembled and welded. (the red arrows are the spring pockets)

To me, it's hard to imagine what it would take to make a huge, intricate castings like a loco frame. There are still some cast steel flatcars around my location. I look at them and think of what all went in to just making something as simple as that. It makes your head spin.

Yeah I know all about that video because I made that video!

Well Rick as usual I have to disagree with you. I have also worked in a foundry making massive flood gates for dams. I am still very much in the active work force and have a long manufacturing history. I can tell that most people in here have experience but it is from 30 years ago and the majority of their opinion is typically speculation.

I spent the majority of my career as a welder, fabricator, and mechanic. I strongly disagree when you said "nobody, and I mean nobody in their right mind specifies large castings anymore if they can help it". That is a absurd statement. The casting process has changed very little since it's conception. It hasn't changed because it works. It's cheap, it's quick, and it's reliable. Why would you change it? Cast iron and steel has proven it's worth time and time again. Then industry has hardly moved away from it. Can you show me examples where parts that were formed in a foundry are now being made by welding and fabrication?

I am not going to get into the whole cast VS fabrication debate. I have already said you can make just as strong as a part using either process. I disagree that metal fabrication is cheaper and faster or stronger. Metal fabrication is painfully slow especially with large projects. With the photo I posted of that giant press in China. Even with a army of welders that would probably take you at least a year if you had to fabricate that. Or you could cast that in a few months.

Finally welding large, thick, metal is difficult and slow. I once welded steel over 2 feet thick. I was running 425 amps with a 1/4 electrode. It took considerable preheat. Let me tell you the light coming off that arc was extremely intense even with the darkest lens. After a few hours you were spent. I also used powder welding to weld very thick walls on a dry dock when I worked in the shipyards. Extremely slow process and expensive.

What specific locomotive is this truck in your photo from? What parts in the photo are fabricated rather than cast?

Looks like a HTCR-6 truck, as used under the SD70ACe-T4. Considering the grey colour I'm going to guess that is a Union Pacific locomotive.

I believe the truck frame is fabricated on these. Previous EMD truck designs, up to and including the common HTCR-4 used cast frames.

GE/WABTEC still uses cast truck frames, I believe they are made in South Africa or China.

I know for sure that the CSX AC6000s had trucks that were definitely cast in S. Africa (had SAR) cast in them.

I had no idea that you lurked around this corner of the interwebs.

Great presentation by the way!

Thank you to those who responded re stress relieving.Glad to hear it is still being done.
Re the frames - being a one-off, the welded frame seem the best bet. At least changes are more readily made during the process, should they become needed.
There were no doubt instances where those big castings had issues, hollows spots, or pattern slippage. A lot of things can go wrong. Once you get 'er poured and find a major defect, somebody is going to have to run for cover, or join the rejected part in the melting pot!!