Date: Thu, 6 Jan 2000 09:30:53 -0800
From: Doug Boyd <[EMAIL PROTECTED]>
To: [EMAIL PROTECTED], [EMAIL PROTECTED], [EMAIL PROTECTED],
[EMAIL PROTECTED], [EMAIL PROTECTED]
Cc: [EMAIL PROTECTED], [EMAIL PROTECTED]
Subject: Wingrods, Ejector pins, and some Metal-urgy and the search for so
mething stiffer
Message-ID: <AD1DA646FC8BD311A24F009027BBDC37189C0B@NTS-MAIL2>
Sorry if this is a bit long, but the ol' winch doc likes to tell his
stories...
I was over to the Winch doctor's hut in the woods last night and the subject
of wingrods came up. He told me about the 'good ol' days' when wing rods
traveled in identical pairs, and you would rarely see a wing rod bigger than
1/4" dia. The venerable Windfree had 2 3/16" dia pre-bent wingrods. Usually
they were "music wire" or "piano wire" He told me that these terms referred
to spring steel that has been hardened, and drawn back, or 'tempered'. He
said, "I see that vacant look in your eyes, again grasshopper, are you
confused?"
"Of course I'm confused, Doc, I always get confused when I come over to your
hut. I thought metal was metal" "Wrongo!" sez the ol' Winch Doc. "Let me
'splain some of these terms to you, composite boy." The Winch Doc strolled
over to his chalk board, and put on his mortar board hat. "Steel," he says,
"STEEL has carbon in it. Not the kind of carbon you like to put in those
suck-bag wings of yours, but the carbon is one of the elements that give
steel some of it's unique properties." He picked up a chunk of some kind of
metal. "This piece of steel could be in several different states. If we heat
it up to say, 1400 degrees F, or about a cherry red color, and allow it to
cool in air all by itself, it loses a lot of it's hardness, or as we
metallurgists say, it becomes ANNEALED! like when you ruined my Sailaire
wingrod roasting beers last summer" I winced, remembering the severe
chastising I received. "If we heat this piece of steel to cherry red again,
and plunge it into some oil, what do you suppose happens?" I knew the
answer. "It makes a BIG STINK, and your mom gets after you!" He frowns, and
reminisces "I love the smell of heat treat in the morning... It gets HARD!"
Then he adds, "It gets hard, but it's also brittle, not tough, almost like
glass, we need to DRAW it BACK, or TEMPER it, by re-heating it to a slightly
bluish or 'straw' color, and allow it to cool by itself. This will make it
less brittle, and tougher"
"Wait a minute, Doc, do I have to do all this hocus-pocus just to get a hard
wingrod?" The old Winch Doc frowned again, "Wippersnapper! Always looking
for the easy way, aren't you?" I nodded, yes. "Then you might as well get
some EJECTOR PINS! These are used in the mold-making business, they have to
be hard, tough, and very smooth, kinda like me!" I winced again, I knew he
was really on a roll, and he liked showing off his vast knowledge. "Let's
look on the internet." We stepped over to his computer, and, well, let me
tell you, the Winch Doctor doesn't throw ANYTHING away. How he can surf the
net with a computer that uses Fortran cards, is beyond me. "Here it is:
http://www.ntm.com/
These guys sell ejector pins by the truckload. they ship for free. You want
the straight type, and you'll have to cut the head off with your Dremel
cutoff wheel." I looked and saw that I could get a 5/16 diameter X 14" long
pin for $4.80. They had all the popular fractional inch sizes I could want.
Great! I ordered the rods I needed, plus one to replace the Doc's Sailaire
rod that I roasted.
Hope this helps.
Doug
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