Memory metal frames

[eyestrain]

So, I've got a bone to pick with some of these memory metal frames. When we first opened a year ago we did pretty well with selling them. Lots of oohs and ahhs when you twist the temple around your finger. Then they started coming back broken. I bet 80% of our warranty jobs on frames have been memory metals. All of them we see back have snapped in half right at the bridge. Does anyone else have this experience with these things? I carry a couple different lines of them from a couple different manufacturers and they aren't exactly cheap frames.

[For-Life]

they break, because customers get so excited about the twisting, that they show everyone.

The key thing is communicating to your clients that while these frames can do amazing things, do not show them off, because they will break.

[chip anderson]

For-Life:

I would have agreed with you the first few years these were out but I find most of them break (even with patient's that are not inclined to demo them) after about 3 - 3.5 years. When the concept was new, we found that if we kept a sample for demo's it might not break but it would become warped (I later found that some of these will return to origional shape with heat).
I often wonder how the skunk-works could make an airplane that would fly 3500 miles an hour, and last 40 years and our frame suppliers can't make a frame that will last 5 at a lot slower speeds.
In a small point of agreement we have found that if we sell anything and claim it's "unbreakable", it might be if we tell a child's parents only about it. But if you say this in hearing distance of the child, you gonna eat it within 3 weeks.

Chip

[bob_f_aboc]

I do the same thing when showing memory metal frames to kids/parents. I will tell the kid to look at that green frame or out the window or at a magazine and then show the parent what the frame can do.

The only time I have problems with this is when the happy soccer mom with "perfet angels" calls the angel over and says, "Look what this does. (Twist, twist, twist, twist)"

When she does that, I know the frame will be back in pieces within 2 months. It doesn't matter at all if they chose the memory metal, titanium, zyl, or chipmunk horn. As soon as the kid sees 1 frame that can bend and come back, they think all of them do.

I am rapidly phasing out all of the kids memory metals and significantly limiting the adult versions. The men that insist on those all want similar styles, so it is easy to do.

There was also the time we had a demo memory metal frame to show patients. I was the lucky soul that was showing the "benefit" of memory metal and bent the frame for the 12,132nd time and sssnnnnaaaaapppp!!! 2 pieces of frame and a patient walking out the door.:(:angry:

[Happylady]

I have never liked memory metal frames. I don't like that I can't adjust bridge or temples (except at the ends), I think they get out of shape easily, I think they are over priced.

[cocoisland58]

Silhouette and Nike. They don't like the cold weather. Get a cold snap and you get broken memory metal. Two Silhouettes (minimal art) this week. One guy was ice fishing and the other works outdoors. Both broken in the same place and both under warranty (one year). We had an issue with Nike a few yyears ago (in the winter) where the bridge just snapped. My fiuance was one of them. Nike was aware of the issue and since then we have had no problems any time of the year. Silhouette chooses not to acknowledge any metal issues but they will replace them under warranty.

[Johns]

I love them, but don't carry any of the name brands. We demo them only for the parents, and NEVER in front of the children. They are our highest referal frame, and our highest profit margin frame.

What's not to like about them? Light weight, no spring hinges to come apart, strong, tons of colors, and easy to adjust, using the 3 adjustment points. My staff sells the tar out of them, and I love working with them.

We carry 18 different styles for kids, and 11 for adults, including a great drill-mount that is one of the best we've ever had.

And yes, we did carry the Nike at one time, and had an issue with some of them in the cold. Not often, but it was always in the cold, and that hurts when you have the kind of money wrapped up in them that they charge.

[EdgeOptical]

we carry them, i have a pair, and we have been very happy.
The newer styles that dont have the round rod and 2 collars in the bridge seem to hold up much better, alot of the older styles the solder inside the collars would come loose. maybe since its more material its holding up better.

we are getting 95% of our kids memory frames from an independent manufacturer, and have been thrilled. Their adult line has been beyond great for us also, great price point for us and the patient, and no complaints with quality. anyone interested in looking into these let me know, i can PM you the company name. (dont want to step on anyones toes, or make it seem like i work for the company or anything. i encourage everyone to work with these guys, TOP NOTCH all around)

[THE MEB]

frames breaking due to cold weather reminded me of the old nylon frames, which I understand are still available. We had to advise patients to soak their frames overnight, once a week, in water to prevent frmaes from breaking in the winter.

[Chris Ryser]

Another name for a shape memory alloy is a nitinol alloy.( that's the substance it's made from)

after all memory metals have been around since 1930,

Eyeglass frames made from titanium-containing SMAs are marketed under the trademarks Flexon and TITANflex.
Shape memory alloys are typically made by casting, using vacuum arc melting or induction melting. These are specialist techniques used to keep impurities in the alloy to a minimum and ensure the metals are well mixed. The ingot is then hot rolled into longer sections and then drawn to turn it into wire.

The first reported steps towards the discovery of the shape memory effect were taken in the 1930s. According to Otsuka and Wayman (1998), A. Ölander discovered the pseudoelastic behavior of the Au-Cd alloy in 1932. Greninger & Mooradian (1938) observed the formation and disappearance of a martensitic phase by decreasing and increasing the temperature of a Cu-Zn alloy. The basic phenomenon of the memory effect governed by the thermoelastic behavior of the martensite phase was widely reported a decade later by Kurdjumov & Khandros (1949) and also by Chang & Read (1951).

The way in which the alloys are "trained" depends on the properties wanted. The "training" dictates the shape that the alloy will remember when it is heated. This occurs by heating the alloy so that the dislocations re-order into stable positions, but not so hot that the material recrystallises. They are heated to between 400 °C and 500 °C for 30 minutes. Typical variables for some alloys are 500 °C and for more than 5 minutes.

They are then shaped while hot and are cooled rapidly by quenching in water or by cooling with air.

use in Aircraft
Boeing, General Electric Aircraft Engines, Goodrich Corporation, NASA, and All Nippon Airways developed the Variable Geometry Chevron using shape memory alloy that reduces aircraft's engine noise. Boeing's upcoming aircraft, the 787 and the 747-8 will be equipped with this new technology.

[Chris Ryser]

frames breaking due to cold weather reminded me of the old nylon frames, which I understand are still available.

Metal fatigue

The de Havilland Comet was the world's first commercial jet airliner to reach production.[3] Developed and manufactured by de Havilland, it first flew in 1949 and was considered a landmark British aeronautical design. After a successful introduction into commercial service, early Comet models suffered from catastrophic metal fatigue, causing a string of well-publicised accidents.

The Comet was withdrawn temporarily and redesigned. The Comet 4 series subsequently enjoyed a long and productive career of over 30 years, although sales never fully recovered. The Hawker Siddeley Nimrod, the military derivative of the Comet airliner, is still in service. The original decades-old airframes are being rebuilt with new wings and engines to produce the Nimrod MRA 4, expected to serve with Britain's Royal Air Force until the 2020s, almost 70 years after the Comet's first flight.


RoleAirlinerManufacturerde HavillandFirst flight27 July 1949Introduced2 May 1952 with BOAC