Only two rows of superheaters?

Was the cracking in the boiler shell, and resultant repair in the lower portion of the boiler?

Yes, mostly in the bottom. That lower part of the boiler, which had no tubes, made for a large area of relatively cold water, compared to what was above it in the tube bundle.
That made for a lot of thermal stresses.

So put tubes there in the new boiler?

Is this complicated?

I agree, the stays are unusual. No Form 4 calculations were made on the existing boiler, so we will never know if the original CNW design would have passed the current Part 230 requirements. It is a moot point since the locomotive will be getting a new boiler. The R1 class was very numerous with quite a few obvious differences within the class, including the boiler. Among the surviving R1 drawings is one for a "new" boiler. Existing records indicate that this boiler was fitted to only 6 locomotives. Comparisons of those drawings to the existing 1385 boiler and frame indicate that the new design was not a direct replacement.

As far as "original fabric" is concerned the only new part of the locomotive will be the boiler, the wooden portions of the cab and the drawbar casting in the frame. Frame and running gear are still 90% original. On the frame, the original drawbar casting was cracked and broken some time in the CNW days and had several welded repairs that had failed making further repairs impossible. The casting is being replaced with a weldment. The steel sheathed wooden cab is being rebuilt using as much of the original hardware as possible.

In reality, Mid-Continent is doing what the railroad would have done when the locomotive came in for heavy repairs. The C&NW was known for being cheap, but they would have done what was required to keep the locomotive in "safe and serviceable" condition. If that included a new boiler, cab and tender, that would have been done. However, "new" for the Cheap & Nothing Wasted would have been a swapped cab and tender, so the original fabric would have changed from "as built" to "as rebuilt" and we would probably have never realized that.

I'll be very interested to hear Matt's take on the original boiler layout. I'm thinking maybe it was done early in the first days of superheating conversions. They might have thought it was beneficial to reduce the number of small tubes to increase flow through the larger (superheater) tubes or something similar.

They did a lot of goofy things in the early days of superheating, like dropping boiler pressures down from the established norm of ~200 PSIG back to the ~160 PSIG range (I believe cylinder sizes were enlarged on new locomotives to compensate) thinking that superheating would more than make up for the pressure difference. That theory didn't last long at all.

While we can no longer ask the folks who originally made the boiler changes I'll offer another point to consider. The portion of the rear tubesheet that is now blanked and carries the through stays falls below the border of the arch brick in the firebox as it was applied by the C&NW. How well would the engine draft if a small bundle of tubes were sucking below the brick and the rest above it? mld

PS Matt, thanks for posting the pictures (including Rick Peters). Your design proposal was not lost, the money had not gotten raised to carry it forward.

Interesting to see how different railroads modified their motive power from saturated to superheated steam.

Below is a 1903 drawing of the back end of the boiler of the soft coal saturated steam 2-6-0 500 series fast freights of the Delaware, Lackawanna, and Western Railroad, showing the original tube configuration.

Below that is a 2012 view from the inside of the firebox of DL&W 565, a 2-6-0 which was built by ALCO Schenectady in 1908, and so it is a locomotive of similar vintage to that of C&NW 1385. This picture shows the tube and flue configuration the DL&W selected when upgrading the locomotive to superheat and piston valves sometime around 1918.

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This could be an opportunity to use modern cast arch material to eliminate a lot of the bulk, and relocate the arch tubes to further down so you can get all the tubes in you can fit and avoid those damn braces. Perhaps more smaller arch tubes as well? Thermic syphons instead? Lots of room in a new build to gain efficiency and reduce headaches.

dave

Here is the history as I know it about the new boiler for the C&NW 1385. Some of this history is before my time with MCRM and went back to other members of MCRM for information to insure I got it correct. So to the best of my knowledge here is what I know.

The 1385 came out of service in 1998 because of known boiler issues and that it had hit the end of it's tube time and all extensions allowed by the FRA rules of the time. This was not the first time it have been out of service for boiler issues during its life at MCRM. There had been work done throughout the years at MCRM and some major work done before and during the time spent on the main line for the C&NW.

When it came out of service in 1998 a repair plan was put into place working in conjunction with the WI state boiler inspector and work began. This approach was necessary because we were also under state jurisdiction in the pre-Gettysburg world. After that dark date we all know changes have been made. However as the work progressed the repair became larger and larger and work was finally halted when it was realized the costs of repair would exceed the funding on hand.

The statements presented in above posts do a good job of representing the condition of the boiler.

In 2001 MCRM had an outside contractor knowledgeable and well-practiced in rebuilding locomotive boilers review and give a proposal on rebuilding the boiler. We also went out and reviewed the design with an outside boiler house and reviewed a proposal for building a new welded boiler. From this information the Mechanical Department staff and Broad of Directors discussed these options and made the decision that the best option to insure that the engine would run for many years to come was to build a new boiler.

From 2001 until 2011 preliminary designs were put on paper, kicked around and discussed, however without the complete funding in place little action was taken. With the Wagner Foundation matching grant and support, work began in earnest on the 1385 rebuild. At this point the board placed the responsibility of a successful return to service on the 1385 Task Force. Over the last 3 years much of our (task force) efforts have been on other areas of the rebuild. In the last several months we have been working with others from the industry and have begun to finalize the designs. We have been reviewing some of the less than optimal design points that Hamster stated (among others) and are working on design changes to improve these. Once this work is completed the design will be going out for a third party review and then it will be off for build. We hope to have in the build process by late summer.

Mike Wahl
1385 Task Force Member

The problem: What Lincoln Penn said...


My Comments:
I am going to guess 1385 was built as a soak. Within a few years they added the superheaters and the brick arch at the same time, but they did the upgrade in-house. The RR decided to use a stock arch brick for all the installations and modified the tube sheets to make life easier for the roundhouse crews but nightmares for the backshop boilermakers....

The Solution: What Dave said.... (minus those thermic syphon doohickeys)

M. Austin, could you please offer some rationale to why siphons would or wouldn't be a good engineering change to add to this boiler? I ask this not to question any body in what would be right or wrong or best approach, but educate myself on the subject. The tea kettles I have been around did not have such modern appliances in design or ever added on. This has turned into an interesting discussion and I find it educational and assume others do too. I get the thermic situation of water temps differing with current design and had kind of thought that siphons might of been helpful. Reading on it sounds like a major re-engineering of the firebox might take away the need for siphons? If you would be so kind could you elaborate on the subject some more?

I am not involved in this project what so ever and am way out of the loop on the design changes planned past or present. Want to thank all contributors to this thread. I think if we are still going to be running steam into the future the replacement and design modifications of many boilers is going to happen. Maybe not in the hundreds of locomotives but lets face it some of these great smaller locomotives like CN&W #1385 and a host of others are getting pretty long in the tooth. Redesign/re-engineering of the boilers to bring up to current safety regulations may require a new boiler or stuff and mount the thing. About 10 years ago I tried to do a little hands on research on the subject of who had actually been successful in completing a "new boiler" into an actual running FRA compliant machine. There had a been only a few examples that made it through the hoops. Texas State RR and Monticello's Southern locomotive had success. Point I am trying to make is I think we need to learn from each other on the subject of building new boilers for our old locomotives, as I see it being more common place in the future. I know there are contractors out there that are quite capable of doing this. But there has been a number of failed attempts at doing just this. So this is why I think this thread has a lot to offer us as a "community". Cooperation v/s competition kind of thing.

Regards, John.

I'm not Matt but I did stay in a few Holiday Inns.


The simple answer to your question is that some things are not worth the effort.

Foe example, here we have an old, small locomotive that isn't going to run that often and isn't going to be worked that hard when it does run. Adding a bunch of costly modernizations to something that will never be able to pay back the cost and complexity is not a smart thing to do.

This is why people who restore Model T Fords don't generally add power steering and air conditioning. What's the point?

Yes, design the new boiler so it looks outwardly similar to the old one (except for the rivets, for example). Do the tube sheets as they should have been done in the first place, with tubes in the bottom section. That will go a long way to prevent the cracks from just starting up again in a new boiler belly.

Cast the arch if you want to. But don't waste a lot of time, money, and effort on something that won't accomplish much of any value but will be in the way and will have it's own maintenance headaches and costs..

Related to what LP said above, a thermic syphon is a pretty complex thing to fabricate- photos have been posted here showing the process. It requires a LOT of hard work by men swinging sledgehammers at red-hot steel to form the syphon over forms, and of course it's a multiple-step process. Then there's a lot of welding and a substantial number of stay bolts to be fitted.

By the latter 40's, it seems Security Circulators had replaced syphons on most new modern locomotives, or the N&W's non-proprietary transverse arch tubes accomplished pretty much the same thing. Either would be much simpler to fabricate and install compared to thermic syphons.

Thermal syphons, water heaters, ect. Only saved the railroads considerable money because they had them on hundreds of locomotives. The same way only 6 cents sales tax makes lots of dough for the government when hundreds of thousands of purchases are made.

The only financial impact these would make today would be the crater left in the bank account after they are paid for. The savings on just one locomotive from installing these new would by no means make up for the money spent on them. Especially when the locomotive is rarely operating and rarely making profit, unlike the days gone by.

Lets not even consider the extra maintenance.

It just adds up that there is no practical reason (at least financially) to install these "extras".