I believe these pictures show the test boiler that has survived in the collection at the Museum of Transportation in St. Louis. Here's an earlier thread that discussed it:

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Thanks for posting, Matt. That's the first time I've ever seen that article.

Here's the pic of the 1/6 scale boiler from the earlier thread:

Was that the boiler they were proposing to go with the 4-8-6 that they were pushing at the end of steam?

It would be great if the T1 group would consider the Double Belpaire boiler and Franklin's long compression poppet valve gear that was also a feature of Lima's proposed 4-8-6. And if they would incorporate the ACE3000's balanced opposed cylinder drive, they would have a design more than capable of 130 mph. But of course it wouldn't be a T1.

Tom Hamilton

>Was that the boiler they were proposing to go with the 4-8-6 that they were pushing at the end of steam?

Assuredly so.

An interesting point that I had not realized until Mr. Austin posted the article was that the 4-8-6's drivers could not be larger than about 75".

Be interesting to see if anyone has done stress modeling of the lower 'Belpaire' chamber as it would be if built staybolted, and pressurized.

> It would be great if the T1 group would consider the Double Belpaire
> boiler and Franklin's long compression poppet valve gear that was also
> a feature of Lima's proposed 4-8-6. And if they would incorporate
> the ACE3000's balanced opposed cylinder drive, they would have a design
> more than capable of 130 mph. But of course it wouldn't be a T1.

I would very much like to address these points -- but not at the price of hijacking Mr. Austin's post which is about the historical aspects of the double Belpaire at Lima.

Can you start a new thread with an appropriate title, and raise the issues in that thread?

Thank you for posting this informative article. I had never understood the term "double" Belpaire before.

Now I see that it refers to the top and bottom shapes of the combined firebox and combustion chamber.

Does anyone know if any of the late PRR designs were "double Belpaires or were they all of the top-only variety?

Outside of this 1/6 scale test boiler, no other double Belpaires have been built, unless some enterprising live steamer has built the proposed Lima 4-8-6, which wouldn't surprise me. I believe L. D. Porta proposed a double Belpaire for at least some of his designs.

Wow, so a 1/6 size or 2" scale boiler was built that would fit the chassis of a 4-8-6, which I believe Lima had conceived to look much like the C&O J-3a Greenbriers. And, this 2" scale boiler survives in St. Louis just minutes from a 12" guage railroad that could support such a beast, were it ever to have been built to use this boiler?!?!? i believe this proposed 4-8-6 was to have a 6-wheel trailing truck like that under the C&O H-8 Allegheny's too.

Here that, all your folks at the WF&P?

Sincerely,

Rob Gardner

Thank you, Mr. Odom.

Matt - thank you for sharing this. I too had heard of Lima's proposed Double Belpaire but never came across the article.

General question: is Railway Mechanical Engineer available in its entirety somewhere? I have found a few issues in libraries here in the 'Burgh, but none printed after the early 1920's.

There are known holdings here and there. I believe the RR Museum of Pa. has a somewhat complete set. The Maryland Rail Heritage Library has a scattered selection between 1930 and 1948, but is going through several motions (involving processing a massive estate, awaiting a substantial donation of a set offered from one individual, and a fair amount of trading with two other libraries) to make its set substantially complete. When all is done, there should be at least one full set in library bindings from 1927 to Jan. 1975 (end of publication).

One thing to note is that bound editions of such trade publications (RME, Railway Age, Street/Electric Railway Journal, etc.) often had advertising at the front and back of each issue removed prior to binding. In one case in the above discussion, the set was hardbound by/for the Baldwin Loco Works reference library, and most advertising was removed. Therefore, if you're attempting to research trade advertisements, you may have to seek out someone with complete issues, or ask before traveling any distance.

Good info on RME (the magazine, not the poster- :-) ); thanks for posting that.

One other bit of info on the double Belpaire design- I'm not sure where I read it; either in a Trains magazine special article from the early 50's on the Lima Locomotive Works or in Bill Withuhn's "Did We Scrap Steam Too Soon?" article in Trains:

Lima planned to build a 4-8-6 demonstrator using the double Belpaire boiler and long-compression rotary cam Franklin poppet valves. As an interim measure, they tried to convince the NYC to install a double Belpaire boiler on one of their 4-6-4's, and supposedly they came very close to doing this. It does seem like the lower portions of the firebox would have had an interference problem with the Hudson's tall drivers.

I wonder if there are any drawings of this proposal?