You've asked a simple question that may have a surprisingly complex answer.
What Kristian is talking about is metal that can be given a shape and then
can bend within its spring limits. Like any spring, after you bend it, it
snaps back to its original shape. You need metalworking equipment to get the
initial shape to fit around your knee. I don't think that's what you want.
It sounds like you want something that you can bend to shape, probably by
hand, and then un-bend to take it off. That sounds like the bendable metal
splints that the military uses for temporarily splinting bone breaks,etc.
They're available on the consumer market. Just Google "bendable metal
splint," probably without the quote marks.
Underlying your question is what kind of metal can stand being bent back and
forth, holding its shape after each bend, but which will allow you to shape
it as you need to around your knee. Unless you're into the engineering of
things, buying a bendable metal splint probably is the best place for you to
Metals break after repeated bending into new shapes, unless they're springs
and they don't get bent into a new "set" shape. But you probably want a new
"set" shape each time you put it on or take it off. Finding the right metal,
of the right stiffness, strength, and re-bend-ability (not really a word
<g>) is problematic. But with the bendable splints, the makers have worked
out all of those issues for you.
They may not be the right stiffness. I have no idea. And even they will have
a limited number of times you can bend and re-bend them. They may be very
capable of handling the re-bending, but they aren't meant to be re-used
multiple times. Still, they may have the best properties you'll find for
what you want.
There is no metal that will do this forever. But soft aluminum wire is
pretty good, and cheap. Art stores sell such wire for use as armatures
in plaster sculpture.
Black or galvanized iron wire is also pretty good, in the thicker
grades. McMaster-Carr is a good source.
You will also need wirecutting pliers and a file (to smooth the cut ends
of the wire).
Excellent advice. Pure lead is pretty good too. If you are old enough to
remember the flexi-curve rulers used by draughtsmen, these had two thin
strips of spring steel, one each side of a square lead core (the whole
lot encased in PVC). The sheet lead used for roof "flashing" is pretty
On Sat, 17 Sep 2011 15:42:08 -0700, whit3rd wrote:
In that case, why not just go with mercury, already melted. You
ought to be more sensible about these things! Obviously, strips of
gold, the most malleable metal, would be the best thing to use. I
think a cross-section of about 1/8" x 1/2" would be good, because
that's about the size used for aluminum strips in temporary casts
or braces for wrists, elbows, etc., and gold, silver, and aluminum
all have about the same Young's modulus.
Ah, that's much clearer ... we were thinking that you wanted this to
bend as your knee bent. To use it to hold you knee pads on, you would
want spring steel in the "holding" shape. Then it would _flex_ enough
to remove it, without needing to bend it to a different shape.
As a wild-ass guess, I would say the piece should be about 3/4 to 1"
wide & maybe .030 thick. That would give a pretty strong hold & you
Are you looking for support or protection?
Metals thick enough to provide support won't be flexible enough to do this.
Now if you're looking for protection then I would go with something like
fine ring chain mail. Or woven metal fabric.
A hinged type.
Shake off all the fears of servile prejudices, under which weak minds
are servilely crouched. Fix reason firmly in her seat, and call on her
tribunal for every fact, every opinion. Question with boldness even the
existence of a God; because, if there be one, he must more approve of
the homage of reason than that of blindfolded fear.
-- Thomas Jefferson
Fill a bag with coffee.
Wrap it around you knee.
Pull a vacuum in the coffee bag.
It should lock into position.
To release, release the vacuum.
Pulling a vacuum in the bag will lock all the coffee grinds together.
Coiled extension springs will do this quite well. Not sure I'd want
to kneel directly on them though, but padded both sides should work.
If they are in a flexible tube they won't "catch" on anything either.
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