Chris's Build of Battleship Ohio Engine

[crueby]

looking good
i think of the pattern makers and foundry moulders making the mould to produce a good casting.
john

And the size of the crucible and furnace!

[crueby]

Hi also with our models we can use a 36" or 12" ruler to measure everything from one datum end !! or did they have 45' rulers in those days ??!!


Willy

Hard to keep a 45' ruler in the back pocket!   

[tghs]

for my 1880's to 1900 ship models I have many copies of plans from the National Archives,, the level of drafting and drawing always astound me.. plans for the USS Vesuvius circa 1883.. copy shown is reduced by 50% did have it enlarged to original size ....

[crueby]

TGHS, how do you find/obtain plans from there? Do they have online searching/ordering of the plans?   

[tghs]

most of the nautical stuff is here. they do have some online listings but mainly by description.. which will help if planning a visit,, 
https://www.archives.gov/college-park

[steamer]

My drawings of the ship   USS Ohio I got separately from the Maryland Silver Company      Don't know if they exist anymore

[crueby]

My drawings of the ship   USS Ohio I got separately from the Maryland Silver Company      Don't know if they exist anymore

Maryland Silver Company was bought out by Loyalhanna Dockyard, which is owned by a friend of mine in our local RC boat group! He has been buying up small hobby shops and companies over the years as the owners retire or go out of business. He has a huge collection of ship plans and also the moulds to do fiberglass hulls, he does a lot of fiberglass work including ones for other existing RC boat companies. Not a bad sideline for a railroad signalling engineer working for a big company. I had mentioned this engine to him last month, he said he has the plans for the ship.
Chris

[crueby]

Drew up the crankshaft while waiting for the cylinder parts on the other model to soak in the pickle solution. This crankshaft went fairly quickly, it turns out that each of the four sections is identical, just rotated/flipped for each section.

[tghs]

my plans came through the MSC also ( the owner did the college-park work), some in the pre-internet era (a phone call one night put the owner looking for the Vesuvius stuff for me) had a feeling about the company so I made a purchase of about 6 plan sets.. have had some model ship guys do the college-park trip.. and find some great plans..need to get the Vesuvius of the shelf and finish her..(my navy steam engine drawing came through the owner of Elliott Bay steam launch)   https://www.steamlaunch.com/

[crueby]

for my 1880's to 1900 ship models I have many copies of plans from the National Archives,, the level of drafting and drawing always astound me.. plans for the USS Vesuvius circa 1883.. copy shown is reduced by 50% did have it enlarged to original size ....

I searched the national archives website for the Ohio, and found a listing for construction drawings for the Ohio, but it had no details on what pages they had. Sent the contact there a question asking what they have and how/cost for copies. Got a response back pretty quick, saying they have over 1400 pages on it! They have them digitized already, but they won't be up on the website for a few months, and I should check back to see them when they get posted. Should be interesting to see what they have!

[steamer]

That's awesome can't wait to see them!

[pmerritt]

Am I the only one surprised to see the crankshaft bolted together in sections? I would think the shear forces from an 8000 HP engine would be problematic. Maybe it was normal and I’m showing my naïveté. I guess limitations at the time prevented a one piece crank that large. This is going to be another amazing build!


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[crueby]

Am I the only one surprised to see the crankshaft bolted together in sections? I would think the shear forces from an 8000 HP engine would be problematic. Maybe it was normal and I’m showing my naïveté. I guess limitations at the time prevented a one piece crank that large. This is going to be another amazing build!


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Well, it was common for the shafts from the engine back to the prop to be bolted together too. This engine is around 35 feet long, that would be a tough one to make in one piece. Each joint has eight 3 inch diameter bolts, I don't see any keys in the drawing. They must have got it right, they worked!


 I thought it was clever that all four sections are identical, just flipped end for end and rotated as needed.


Another interesting thing is that the shafts and crankpins are hollow, not solid.

[derekwarner]

So...."each joint has eight 3 inch diameter bolts"...these would have been precision "fitted bolts'..with interference tolerancing...the coupling halves were aligned with transitional temporary bolts, then the actual bolts soaked in dry ice for 24 hours ....[or liquid Nitrogen]....this then being sufficient to shrink the bolts by 0.003" [with Nitrogen] so ultimately an interference fit

[not going too far off thread Chris ......I have personally witnessed by sub-Contract, the shrinking of a 3.000" diameter x 12" long steel pin into in the heads of a Recieving Stand rolling mill cylinder assembly in the Steel industry.......most interesting was the liquid Nitrogen was decanted from an Autoclave on the back a Ford 1/2 tonne utility into a white polystyrene Broccoli box.......  then the pin lowered into the nitrogen via an overhead crane] 

At the time of Ohio's build, the engineers had heat treatment of steel [brick box with coke,  carbon a few old leather boots & a few bones] down pat 

In addition, the total sectional area of 8 x 3" bolts would by far exceed the sectional area of each crank web pin, however this must be based on the bolt sections being in the transition of the interference, otherwise they could shear, like Dominos 

Even today's 100,000 SHP marine diesel engines are fabricated with bolted construction

Derek 

[steamer]

Am I the only one surprised to see the crankshaft bolted together in sections? I would think the shear forces from an 8000 HP engine would be problematic. Maybe it was normal and I’m showing my naïveté. I guess limitations at the time prevented a one piece crank that large. This is going to be another amazing build!


Sent from my iPhone using Tapatalk

Well, it was common for the shafts from the engine back to the prop to be bolted together too. This engine is around 35 feet long, that would be a tough one to make in one piece. Each joint has eight 3 inch diameter bolts, I don't see any keys in the drawing. They must have got it right, they worked!


 I thought it was clever that all four sections are identical, just flipped end for end and rotated as needed.


Another interesting thing is that the shafts and crankpins are hollow, not solid.

Quite common actually,   The reason was to be able to carry a spare crank throw on board for when you're half way around the world and you have a problem.   This was and is very common to carry spare parts on board for breakdowns.   Today, Pistons, rods and rings are common breakdown items and are carried as spares on many modern diesel ships.

Dave