Exercise for engineers: How long will it take for the motor to stall out (or the concrete to fracture)?
https://www.arthurganson.com/concrete-1
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Exercise for engineers: How long will it take for the motor to stall out (or the concrete to fracture)?
https://www.arthurganson.com/concrete-1
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I can't see that motor ever stalling, sorry concrete
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My money's on the concrete. The drive train will fail /wear out sometime before we reach the trillionth year.
He does have some pretty interesting exhibits on his website though.
Confidence: The feeling you experience before you fully understand the situation
I agree with Jerry. It appears that his gears have little if any lubrication.Originally Posted by Jerry Bruette
Last edited by Lee Schierer; 01-06-2023 at 12:49 PM.
Lee Schierer
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Engineer here. What will likely happen is the last gear reducer will fail. The force multiplication is so great the motor will never stall.
I had a similar situation in my work life. We had a plastic roof vent cover that we wanted to open and close remotely. Think small skylight. The motor we used was a small 12V motor of the type used in cordless electric tools and appliances. About the size of a "D" size battery. We used in on many other products so pulling it from stock made sense. The problem was it was normally used to drive an axial fan blade. No load RPM was about 3500. We designed a gear train that would reduce the RPM on the output shaft to about 3 RPM. The torque multiplication was so great that when the actuator we were driving hit full lock all the teeth in the final gear just sheared off like they were made of wax.
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Whatever the weakest link is will fail.
Which is stronger, the last gear reducer or the concrete block?
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No contest IMO... I know it's just a movie, but Andy Dufresne tunneled thru his prison wall in only 19 years with a rock hammer.
And moving onto reality, just water falling from the sky destroyed the entire driveway of my last house in only about 12 years.
Concrete just plain ain't that strong...
========================================
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FOUR - CO2 lasers
THREE- make that FOUR now- fiber lasers
ONE - vinyl cutter
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The concrete block. Concrete in compression is crazy strong. Gear teeth in sheer, not so much. Do the math.
Sharp solves all manner of problems.
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Seems like a GoFundMe should be set up to provide for someone to always keep the gears perfectly lubricated for the next 2 trillion years so we can have closure.
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Backlash? Assuming some average tolerances, 'napkin' says it takes 5,555,555,555.555556 years to get the slack out. Or maybe only 5,555,555,555.555554 years? ...Hope the artist has a sizable oil can and a stop watch; inquiring minds want to know.
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Eiither the gear teeth or the keyway driving the gear are my likely points of complete destruction.
Depends on the area of the cross section of the gear teeth or tooth doing or key applying th actual torque Those teeth are not that large at all compared to the whatever is imbedded in the concrete.
In think you got it right Rob.
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There's no amount of lube in that lashup that qualifies as "enough".
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"Design"? Possibly. "Intelligent"? Sure doesn't look like it from this angle.
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To be fair, he wore it down to a nubbin and replaced it every year or so. (In the book, anyway.)
Yoga class makes me feel like a total stud, mostly because I'm about as flexible as a 2x4.
"Design"? Possibly. "Intelligent"? Sure doesn't look like it from this angle.
We used to be hunter gatherers. Now we're shopper borrowers.
The three most important words in the English language: "Front Towards Enemy".
The world makes a lot more sense when you remember that Butthead was the smart one.
You can never be too rich, too thin, or have too much ammo.
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This was my first thought: in any reasonable accounting, the motor or the first set of reduction gears simply wear out and fail long before the last couple even move, let alone transmit any force to the concrete.
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