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Über Genius
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1970 Opel Gt - Purchased July 1972 - Chartreuse - restored - 3000 miles as of 02-16, 2021 -
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That was amazing - had no idea what all was involved in the process - thanks for sharing....⭐
 

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Detritus Maximus
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I tried to find one single piece of safety equipment....
 

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Seems like wearing open toed slippers there wouldn’t be wise. Imagine dropping a crank on your foot. And then there’s sharp metal chips everywhere.
 

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Where did you find this? Those appear to be old Bridgeport machines. I apprenticed on a lathe like those in 1978 at my local community collage. The guy in step 2 is going to lose a finger slowing the chuck down like that. Check out the used lathe page here. At that time, the Southport lathes were considered the better lathe. Note the "tool" insert. https://machinerypartsdepot.com/used-machine-sales/#usedlathes Thanks for the memories. ;)
 

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Über Genius
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Discussion Starter · #6 ·
Where did you find this? Those appear to be old Bridgeport machines. I apprenticed on a lathe like those in 1978 at my local community collage. The guy in step 2 is going to lose a finger slowing the chuck down like that. Check out the used lathe page here. At that time, the Southport lathes were considered the better lathe. Note the "tool" insert. https://machinerypartsdepot.com/used-machine-sales/#usedlathes Thanks for the memories. ;)
I didn't find the video. It found me.
I like looking at machines and processes and stuff so the youtube algorithm feeds me interesting stuff.

I don't know what brand lathe I learned on but they were old in 1978 when I first started playing with them. They were donated to the school by the Navy and were used to make parts on the ships when they broke. Heavy duty things. They were only 36" bed travel but could take a beating. I would make a left hand cutting tool and see how much meat I could pull off cold rolled steel. 1/4" at 3" round was the stall point.

As for safety equipment. Those guys were wearing clothes that are way too loose and resetting tooling while the machine is still running. Crazy.
I won't talk about the open toe sandals. I tend to do 90% of my machining barefoot. I've only done one piece that weighed as much as a crankshaft though and I won't lie, I was a little nervous barefoot with that one. It was just a piece of 6" round brass 14" long though. Wouldn't have hurt as much as steel because it's a softer metal. Yeah, that's the ticket.

What I found curious about the video is those are obviously production machines. They probably kick out 20-30 cranks a day. And the fact that it appears to be modern times with those being 3 cylinder cranks. I would have thought V6 but the journals didn't seem wide enough. I could be wrong about that though.

The other crazy thing was how fast they were making measurements. Their tolerances must be pretty loose.
 

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Opel Rallier since 1977
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Could be cranks for 3 cylinder tractor engines. So maybe you don't want to buy a Mahindra tractor after all....

American mfrs were turning out cranks this way pre-WWII LOL. My bro-in-law has worked for Landis Machine for over 30 years... they are arguably the premier make of crank and cam grinders in the world. This is not the machinery used by modern mfrs to make cranks!
 

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Exactly, pre WWII technology. Where ever that is, labor is cheap, and life is even cheaper. My hat is off to them for re-purposing all that outdated u.s. machinery. At least these guys are working for a living. Those machines were built to last, and in fact have outlasted their usefulness in the U.S, other than the few hobbyists that have out in the shop and do some "boutique" machining. Things are (and have been for many years) much more automated and precise these days.
 

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Opeler
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Exactly, pre WWII technology. Where ever that is, labor is cheap, and life is even cheaper. My hat is off to them for re-purposing all that outdated u.s. machinery. At least these guys are working for a living. Those machines were built to last, and in fact have outlasted their usefulness in the U.S, other than the few hobbyists that have out in the shop and do some "boutique" machining. Things are (and have been for many years) much more automated and precise these days.
It's in Pakistan.
 

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Über Genius
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Discussion Starter · #15 ·
Ah, the precision! Amazing that anything runs.
Well, I've actually been thinking about the precision quite a bit.
If you have the thrust bearing surface right, you don't need to be that accurate on the spacing of the journals. They could be off by 1/16" and still be fine.
Then the bearing size. If their micrometer doesn't change, they can be within a .004" tolerance and still get 100K out of the motor.
Of course they really need to have the journals offset to the right angle but it looks like they knew what they were into.
 
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Opel Rallier since 1977
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Then the bearing size. If their micrometer doesn't change, they can be within a .004" tolerance and still get 100K out of the motor.
Just so none of the newer guys get the wrong idea, nobody with any decent ability and doing machine work machines journal diameters to a .004" tolerance window. The spec'd tolerance windows even 75 years ago were tighter than that. Even lawn mower engine 'service tolerances' (worn but still usable) are not that large LOL
 
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