[SEL] Curved spokes ...engine rotation

[Mike Royster]

I already tested several for you Steve and it's a good thing I did, all were 
weak and broke.  I saved your life and countless others!!!!!!!

Mike "the good" Royster

----- Original Message ----- 
From: "Steve Royster" <steve_royster at hotmail.com>
To: <sel at lists.stationary-engine.com>
Sent: Wednesday, May 24, 2006 3:36 PM
Subject: RE: [SEL] Curved spokes ...engine rotation


> I'm going to go home tonight and get a big sledge hammer and "test" the 
> spokes on all my engines! Thank you Rob for sharing this information for 
> the safety of the SEL!  Steve Royster
>
>
>>From: "Rob Skinner" <rskinner at rustyiron.com>
>>Reply-To: The SEL email discussion list <sel at lists.stationary-engine.com>
>>To: "'The SEL email discussion list'" <sel at lists.stationary-engine.com>
>>Subject: RE: [SEL] Curved spokes ...engine rotation
>>Date: Wed, 24 May 2006 08:47:25 -0700
>>
>>
>> >If the flywheel runs the opposite way the outer
>> > rim will tend to wan't to fold in on itself.
>>
>>Right you are, Lindsay.  Renowned engine builder Sheldon
>>Brown, partner of Jeremiah Cochran, studied the issue in
>>great detail.  Here is what he wrote in his Famous Flywheel
>>Treatise of 1904:
>>
>>Are your flywheels spoked right, or are they giving you
>>trouble?
>>Many engineers would answer with a rueful "Right!"
>>
>>Spoke Cracking Leads to Flywheel Breakage!
>>Thanks to superior American technology, modern engines are
>>more powerful than ever. At the same time, the trend to
>>lighter flywheels and fewer spokes continues.
>>
>>As a result of the higher stresses and cutting-edge
>>construction, a fundamental design flaw in existing
>>flywheels comes to light. Millions of engines are suffering
>>cracked or broken spokes usually on the left side flywheel,
>>leading to poor fuel economy at best, or getting left behind
>>by your competition, or, in more severe cases, injury or
>>death!
>>
>>Older flywheels were so over-built that they made up for
>>incompetent design by having lots of heavy curved spokes and
>>heavier-than-necessary rims. Even today, most right side
>>flywheels hold up alright, because they still have more
>>spokes than are needed to cope with the usual loads
>>experienced by flywheels...but what about the all-important
>>left flywheel?
>>
>>While the right side spokes tend to hold up alright, the
>>left spokes are often left with insufficient strength. If a
>>left spoke is cracked, there's no way that the engine can
>>run right...you'll suffer catastrophic flywheel breakage due
>>to metal fatigue on the left spokes.
>>
>>Go right now to wherever you left your engine, and check the
>>spoke tension of your right wheel by plinking the spokes
>>with a sledge hammer and listening to the tone. You'll
>>probably find that the right side spokes are at the right
>>tone, but that the left spokes will be less melodious. When
>>you plunk the left spokes you'll notice that the pitch of
>>the plunk is considerably lower than that of the right
>>spokes. Why is this?
>>
>>The Myth of "Bent Spokes"
>>Believe it or not, many of the unscrupulous con-artists that
>>are so common in the engine industry will try to get you to
>>believe that this is a "feature!" Yeah, right!
>>
>>They'll give you some spiel about a mystical property called
>>"curve", which supposedly has something to do with the fact
>>that the belt is on the right side. This is, of course,
>>complete nonsense, since the belt never touches the
>>flywheel, as long as your machinery is aligned just right.
>>
>>History Lesson Part 1.
>>These idiots must have been left back in school when it was
>>time to study history. Everybody knows that in the early
>>days of engines, there was a problem with the left flywheels
>>falling off.
>>
>>This was solved by the Wright brothers, when they invented
>>the system of using a left-hand thread on the left flywheel
>>bolt.
>>
>>Precession
>>You might think that this would not be right, and that the
>>Wright brothers had it backwards, because the friction of
>>the main bearings would tend to turn the right flywheel to
>>the left and the left flywheel to the right. Thus, the
>>right-handed right flywheel should fall right off, while the
>>left handed left flywheel would be left in place...but it
>>doesn't work that way; instead an interaction with the
>>Earth's magnetic field sets up eddy currents right in side
>>the crankshaft, leading to a tendency for the flywheels to
>>tighten themselves, as if by magic.
>>
>>History Lesson Part 2.
>>When Nicolas Otto and Tullio Crossley independently invented
>>the engine, back in the olden times, they used normal
>>right-handed threading for the crankshaft main bearing caps.
>>This worked alright for the left caps, but it was discovered
>>that the right cap would tend to unscrew itself in use,
>>unless the engine was left out in the rain, where rust could
>>help to immobilize the threads.
>>
>>The great British engine inventor Dugald Clerk cured this
>>problem by making the right crankshaft main bearing cap have
>>left-hand threads, so that, even if it starts a little bit
>>loose, it will tighten itself right up.
>>
>>The French were slow to pick up on this improved technique,
>>and many German engines are still made with wrong-way
>>threading, but the rest of the world has picked up on this,
>>and the vast majority of engines now have main bearing caps
>>that are threaded the right way: right threads on the left
>>side, left threads on the right side.
>>
>>The Lessons of History
>>Like many great inventions, bilateral obverse threading
>>seems completely obvious once it has been explained; the
>>solution to the problem of left flywheel breakage is, in
>>fact just a simple matter of using a left-hand threading on
>>the clamps that run to the left side of the flywheel!
>>
>>This completely eliminates the precession effect that tends
>>to loosen left side flywheels in old-fashioned engines that
>>use right-hand threading!
>>
>>Flywheel Building Issues
>>Since I'm a practical mechanic as well as an inventor, I
>>couldn't overlook the confusion that having two different
>>types of bolts could cause. I've come up with an ingenious
>>solution to the problem, however:
>>
>>As an optional accessory item to bilateral obverse thread
>>systems, we are making available special color-coded bolts
>>to help the engine builder keep track of which is which.
>>Since left hand bolts look just like ordinary bolts, we
>>offer special bright red bolts to fit the right-hand
>>threaded spokes still used on the right side of the wheel.
>>This prevents them from becoming confused with the left-hand
>>threaded bolts.
>>
>>What About the Southern Hemisphere?
>>Well, what about it? It is well known that in the Southern
>>hemisphere, the problem of left flywheels loosening up does
>>not occur, but rather it is the right flywheels that loosen
>>up if left to their own devices.
>>
>>Hence, engineers who run engines mainly in the Southern
>>hemisphere should use left hand threads on the right side
>>flywheels, not the left.
>>
>>Honesty compels me to admit that for engineers who live and
>>run engines within 50 miles of the Equator, any bolts will
>>offer little functional value.
>>
>>Engineers who regularly travel back and forth between the
>>Northern and Southern hemispheres would be well advised to
>>swap the flywheel bolts side-to-side after crossing the
>>equator.
>>
>>
>>
>>
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>
>
>
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