How’s this for a crankshaft?
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- Minor Fan
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How’s this for a crankshaft?
Doxford marine engine works, Sunderland - 1960
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- Wm Doxford
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Re: How’s this for a crankshaft?
How big are the big ends going to be for that? Surely they're going to need a box of giant ends?
I think they're still looking for some NOS.
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- Minor Maniac
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Re: How’s this for a crankshaft?
And here is how a similar crankshaft is fitted without taking out the engine - marvellous
https://www.youtube.com/watch?v=2drej_qeRSA
![8)](./images/smilies/icon_cool.gif)
![8)](./images/smilies/icon_cool.gif)
https://www.youtube.com/watch?v=2drej_qeRSA
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- Minor Fan
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Re: How’s this for a crankshaft?
Few more. Doxfords lasted until mid 80s. Building still stands.
I used to work up the Wear from there.
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- Minor Legend
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Re: How’s this for a crankshaft?
Interesting photos, thanks for posting. It wouldn't surprise me if those engines were still going strong, somewhere in the world.
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- Minor Legend
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Re: How’s this for a crankshaft?
Ian Smithskids on the forum has worked on crankshafts a lot larger he may put some photos on ![:)](./images/smilies/icon_smile.gif)
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- Minor Fan
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Re: How’s this for a crankshaft?
Brilliant photos , imagine having a drop off turning one of those cranks. ( drop off engineering term for mistake where you have to scrap the work peice)
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- Minor Maniac
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- Minor Fan
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Re: How’s this for a crankshaft?
One of my jobs until I retired was eddy current testing the internal threads of the conrods off similar sized marine engines during refurb. I never found one that was cracked.
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- Minor Maniac
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- Minor Fan
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Re: How’s this for a crankshaft?
I never thought of thatphilthehill wrote: ↑Sat May 22, 2021 3:18 pm So - eddy's not only outside the ship but also inside the engine.
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- Minor Fan
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Re: How’s this for a crankshaft?
And this is when you have to take the full engine out Replacing the gensets on CCGS Cornwallis at out sister ship-repair yard via a ‘softpatch’ engineered into the ship when she was still on the drawing boards ’philthehill wrote: ↑Fri May 21, 2021 7:39 pm And here is how a similar crankshaft is fitted without taking out the engine - marvellous![]()
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https://www.youtube.com/watch?v=2drej_qeRSA
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- Minor Addict
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Re: How’s this for a crankshaft?
Amazing. Can you imagine how they clocked the shaft with the dti.
They are using a 4 jaw chuck and a centre on the tail stock.
This looks good for the main bearings, but what kind of machine could machine the big end journals.
The offset is huge.
The face plate looks like it has the radius.
Whats going on with the tail stock?
Looking again, i don't think the 4 jaw is large enough.
It needs a larger diameter for the jaws to work.
It looks like the journal is very near to the diameter of the chuck.
They are using a 4 jaw chuck and a centre on the tail stock.
This looks good for the main bearings, but what kind of machine could machine the big end journals.
The offset is huge.
The face plate looks like it has the radius.
Whats going on with the tail stock?
Looking again, i don't think the 4 jaw is large enough.
It needs a larger diameter for the jaws to work.
It looks like the journal is very near to the diameter of the chuck.