I have some 'Flexon' memory metal glasses frames that need adjustment where they
rest on the ear. All I know is that this is some kind of Ti alloy that is in the
superelastic phase at room temperature. This means that it always wants to
return to the original shape once the bending force is removed.

What little information I can find on the web suggest that these can be
permanently bent into shape but so far I've had no luck at all. I'm worried that
if I just keep increasing the force then it will snap before it permanently
bends. Is this likely to happen?

Other information suggests annealing the metal at 400-500 deg Celsius, but that
will mean destroying the plastic coating where it wraps around the ear.

Mike

"Mike B" someone@noplace wrote in message
...

I have some 'Flexon' memory metal glasses frames that need adjustment
where they
rest on the ear. All I know is that this is some kind of Ti alloy that is
in the
superelastic phase at room temperature. This means that it always wants to
return to the original shape once the bending force is removed.

What little information I can find on the web suggest that these can be
permanently bent into shape but so far I've had no luck at all. I'm
worried that
if I just keep increasing the force then it will snap before it
permanently
bends. Is this likely to happen?

Other information suggests annealing the metal at 400-500 deg Celsius, but
that
will mean destroying the plastic coating where it wraps around the ear.

Mike

I have had these glasses before. If you bend them beyond a certain point the
relaxed shape will change. Don't worry, they are nearly impossibly to snap.
It is best if you do not try to bend them in a small area; try to bend a
large part of the earpiece. I would guess that you have to bend it to a
radius of 10 or 20 times the width before it takes permanent set.

That said, it is really hard to get them adjusted just right.

In article ,
"anorton" wrote:
That said, it is really hard to get them adjusted just right.

....You're supposed to adjust them by bending the non-memory-metal parts,
which bend quite cooperatively. Put a few decades on the things myself.
Broke a LOT less than the heavy metal frames before them, which broke a
lot less than the plastic frames they started me out on as a kid...

--
Cats, coffee, chocolate...vices to live by
Please don't feed the trolls. Killfile and ignore them so they will go away.

On 1/14/2012 11:22 AM, anorton wrote:

"Mike B" someone@noplace wrote in message
...
mean destroying the plastic coating where it wraps around the ear.

Mike

I have had these glasses before. If you bend them beyond a certain point
the relaxed shape will change. Don't worry, they are nearly impossibly
to snap. It is best if you do not try to bend them in a small area; try
to bend a large part of the earpiece. I would guess that you have to
bend it to a radius of 10 or 20 times the width before it takes
permanent set.

That said, it is really hard to get them adjusted just right.

I broke one set, I was just twirling it in my hand while thinking, and
the temple snapped in half - but it lasted longer than earlier ones - as
said above, bend beyond the elastic limit and it will stay that way