Interesting stuff, obviously thicker sheets mean more weight, does this create a balance issue then? Should contribute to tractive effort though. With the thicker sheets is it possible or even desireable to raise the working pressure? Back to the 1361, I know she had a new backhead sheet installed, but if I read your post right,
it can stay, but the outer wrapper would need replacing, just the roof or the sides too? Sorry for all the questions, but I'm still trying to understand how much work (and cost) it would be to undo all the work done to 1361 to make her compliant. I realize that the Long Island engine is your project, but I'm also assuming that there are certain similarities between them.

Going from a 3/8" plate to a 1/2" plate increases the weight of the roof sheet by about 300 lbs. Remember that the engine originally had nuts on every bolt which are no longer there, so it's probably a wash.
A thicker sheet will give you a greater working pressure for that part, but it won't help you with the other components. Remember also that the running/driving gear was designed for a given working pressure and stresses. You have to take that into consideration even if the boiler is capable of a higher MAWP.

While there are many similarities between the G-5 and the K-4, I just can't comment on the #1361 without looking at all of the numbers.

Just hypothetically, if one were to remove a thin outer wrapper, and replace it with a thicker one, would one just remove the double row of rivets shown in this picture, remove the stays attaching the outer sheet to the inner sheets, and replace? would the side sheets be ok to leave? [url][http://www.trainweb.org/horseshoecurve-nrhs/Photos/K4/added_AUG04/32.jpg/url]

On the G-5, we removed the roof sheet and included the top 4 rows of the outside side sheet. There were two reasons we included that part of the side sheet: 1 – The top 2 rows were flexible staybolts, and the sleeves were shot and needed to be replaced. 2 – The section of outside side sheet from the welt to horizontal rows 4 and 5 (from the top) averaged around .340” thick. The .340” thickness was only a few thousandths over the minimum required. Between rows 4 and 5, there was a weld the entire length of the sheet, and below the weld the sheet averaged .437” thick.
The conclusion was that since we would have to replace all of the sleeves and bolts anyway, why put them into a section of sheet that barely made the cut. (No pun intended)
The new roof sheet will include the welts and the side sheet rows mentioned above, all in one piece. The welts will go away and there will be an internal doubler where the welts were. The new ½” roof sheet will be welded to the existing 7/16” outside side sheets. The 7/16” thick outside side sheets are more than adequate for the bolt pitch and working pressure.

Hypothetically, I’d rather have a NYC Hudson in the shop.

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Rick, Just so I understand this, you'd take the NYC over the N&W?

Robert Yuill

Bob,

Maybe you can get some more information out of Rick regarding the condition of that Hudson's roof sheet. I think one N&W engine sets his migraines off enough as it is.

This is destined to set off a war amongst those who take these kinds of jokes too seriously.

So SRC managed to hide a NYC Hudson all these years? Wow. And only a few hours early. And to think most folks consider SRC to be a PRR shop. :-)

Bob

"Rick, Just so I understand this, you'd take the NYC over the N&W?"

Now Bob, you know better than that!
I'm just not sure that we are worthy enough to have one of the big three in our shop. That's because we have a couple of non-believers who work here that don't understand that A, J, and Y are the finest letters in the alphabet.

Rick

I thought M was one of those letters too?

My grandfather ran class M's on the N&W in West Virginia. N&W is my heritage. I've spent my time at the throttle of a steamer, but will tell you that I got to sit in the engineer's seat of #475 at the shop, and you have to be a monkey to run that thing.