Open To Suggestions...

[eyecarepro]

Okay, so my store has this patient who's a high myope, with a moderate amount of cylinder, that I just edged a pair of of high index 1.70 FT-28's a couple of days ago. My edger turned out a pretty decent edge polish on them. We polish pretty much anything semi-rimless, and this was a semi-rimless mounting. Apparently this patient recycled her teenage son's old glasses for her own and his prescription was quite a bit different than hers. I wasn't around when she came to pick her finished glasses up, but from what I hear she had a COW when she saw how thick the edges were. I'm talking, IN TEARS almost. Now I know the secrets behind turning out the thinnest looking finished eyewear; frame size, shape, pt's pd, base curve, bevel placement, etc.,etc. That being said: We offered her the option of choosing another frame, complimentary. But she didn't like ANY of the frames we had. I think we have a pretty decent selection, actually. So, if she stubbornly sticks to her guns on this frame, that I know her PD is no where near the frame's total size, what more CAN I do? A -8.00 something in both eyes, a RECTANGULAR frame, semi-rimless, we already have her in a pretty flat base curve, and a 1.70 high index to boot. Should we be able to help 100% of the people 100% of the time? I'm not throwing in the towel, I don't really have that luxuary anyway, I don't own the business. I just want to come to the best resolution for the customer, and the least expensive onefor us. Does anyone have any suggestions?

[cinders831]

Yes tell the brilliant broad who expects her lenses to look like shes a minus 2 to go to lens crafters as they have the best lenses...(sarcasm) and let them pay for her unhappiness. If someone educated her about her lenses and the frame choice she made then your office shouldnt be giving complimentary anything. She was warned and made the choice. If no one spoke up and gave her any options then perhaps you have to eat some money and learn a lesson. In any case good luck and sorry for the crabby rant, one of those days.

[Framebender]

but in the spirit of trying to work things out. . .! Do you have access to a facet wheel and a good set of edge kote pens?? Grab a scrap lens and edge kote it so you can show her what it looks like. Pitch the facet as something her friends don't have and would be hard pressed to get. She'll like the high gloss. Help her coordinate the edge color with her complexion and frame color. Offer her coffee or a water while all of this is going on. Take the nylon cord and dye it to match the edge kote.

If you pitch this right and make her feel important she'll be alright. At this point I would get the office manager or owner to pitch it. A fresh person of authority is a good thing right now. We just did this for a lady -8.00 in her old 56 eye Tura semi rimless and that turned out to be one hot looking pair of glasses!

At this point you either save it or you don't, but you can at least feel like you gave it your best shot. Good luck to you!! Have some fun and make some money!! :cheers:

[rbaker]

A journeyman optician would have resolved this thickness issue was BEFORE the lenses were fabricated. Whoever took in the job should have noticed that the lenses were of quite different powers and discussed this with the customer.

[thep]

I wasn't aware that there is a 1.70 ft available!? Are you sure it's not 1.67?

[spartus]

A patient with that high of an RX should know there are still limitations on what they can feasibly wear. For something like a -8.00 in rimless, I'm running to Darryl's thickness calculator for a ballpark figure of ET they can expect.

Not that any of that helps with your problem. The "You know this is gonna be ugly" ship has sailed. Obviously, the best way to hide the lens thickness is going to be a small, roundish zyl frame, but that's hardly something you can tell her at this point. The facet idea doesn't sound half bad, considering the other variables in this particular case.

What's worked for me in the past, and it may still work now, is to simply tell the patient, "You know you have a high correction, and not all frames are suitable for all uses. This frame, unfortunately, happens to be one of those." Having an uncut -4.00 or so CR39 lens that they can hold sometimes helps them to understand edge thickness. You can show the effect of decentration using gigantic and tiny frames.

We spend so much time thinking about this stuff a great deal of it seems second nature. I'm sometimes surprised at a patient's awareness (or lack) of what I consider common knowledge regarding lenses and frames. Not that I'm knocking the average patient, mind you--I wouldn't presume to know everything about everyone else's job, so why should they know mine? However, it sounds like a little education in this patient's case may go a long way.

[shellrob]

I would say if you educated her already on what to expect as far as thickness goes before making the glasses, she shouldn't get anything for free. If she wasn't educated on how thick it would be, then that' another story.

[Happylady]

I wasn't aware that there is a 1.70 ft available!? Are you sure it's not 1.67?

Hoya makes a 1.70. However we never edge it in office, it is very smelly when cut.

Essilor makes a 1.74 now in single vision and in Panamic.

[SpecialT]

Forget trying to make this thing work with some jazzy optical work, it just isn't going to make a difference. It sounds like you are in a situation where the sales person did not explain things properly, or you would not be offering things for free. If this is the case, send out your top negotiator and get things done the right way. Don't continue to work with the same frame, she is obviously unhappy with its appearance and though you could make some minor improvements they would all be minimal at best. This is a problem that will be solved with smooth talking and a sense of diplomacy, not your expert ways with lens fabrication.

Good Luck!

[GOS_Queen]

Not that any of that helps with your problem. The "You know this is gonna be ugly" ship has sailed.

OMG - I love that phrase ... and it's so true !! I wish I had that when I was dispensing ... :cheers:

[RT]

Actually, HOYA does not make a 1.70 index FT28--only progressives and aspheric SV. I suspect this was really a 1.66 index.

[High_Abbe]

Push the easy button!

[eyecarepro]

Thanks for the clarification of the index of that FT-28, you are right- it WAS a 1.67. Still no resolutions met yet...in the works. I WISH I could refuse to cut the 1.70n lens in that dinky little lab I work in. Talk about FUMAGATING! I actually had someone who worked in the office suite next door to us come over to find out what on earth was causing that terrible smell in THEIR office!

[Happylady]

Thanks for the clarification of the index of that FT-28, you are right- it WAS a 1.67. Still no resolutions met yet...in the works. I WISH I could refuse to cut the 1.70n lens in that dinky little lab I work in. Talk about FUMAGATING! I actually had someone who worked in the office suite next door to us come over to find out what on earth was causing that terrible smell in THEIR office!

We never cut 1.7 index lenses. They just smell too bad and I am sure it isn't healthy to inhale that. The Hoya lab is designed to handle it. I even send 1.67 lenses out if I can.

[snowmonster]

Just curious, did anyone bother to check the CT on the lenses? We recently received a pair of -8.00's in 1.67 that were supposed to be either a 1.0 mm or 1.2 mm CT and the lenses we got in were a 1.8 mm CT and a 2.0 mm CT.

Of course, if you start thick centrally, it's going to get worse out in the periphery.

-Steve

[chip anderson]

Snow: A lens that is .8 mm too thick centrally will be exactly .8 too thick peripherally , it does not contrary to rumor, increase exponentially.

[eyecarepro]

Doesn't ANSI say that unless it is poly MINIMUM CT on a minus is 1.5mm? On poly, I believe it is 1.0. Interesting point though. I will investigate this when I go into work today...

[snowmonster]

Snow: A lens that is .8 mm too thick centrally will be exactly .8 too thick peripherally , it does not contrary to rumor, increase exponentially.

Man, this April Fools thing is brutal to type with today.

Anyway, I was just stating that the lens will be even thicker than it should have been centrally. I'm pretty sure one of our labs does a 1.2 mm CT on hi index. Will check on Monday.

-Steve

[HarryChiling]

5.2.1 Tolerance on Center Thickness

The center thickness shall be measured at the prism reference point of the convex surface and normal to this



surface. It shall not deviate from the nominal value by more than ± 0.3 mm.

NOTE - The nominal thickness of the lens may be specified by the prescriber or be the subject of agreement between



prescriber and supplier

.

The thickness that you specify should be the thickness that you get within + or - 0.3mm of what you specify to your lab.

6.6 Impact Resistance Test Method

The following test method is intended to be equal or superior to that described in CFR 801.410.



The impact resistance of lenses subject to individual tests shall be measured with a 15.9 mm (5/8 in) diameter

steel ball weighing not less than 16 grams (0.56 oz) dropped from a height of not less than 127 cm (50 in).

Lenses should be placed on the test block and base shown in figures A.1 and A.2, object side up, approximately

centered geometrically. The ball should impact within a circle 16 mm (5/8 in) in diameter whose center is approximately

at the geometric center of the lens. However, multifocal lenses may be decentered to be certain that the

ball does not impact the segment line. During the test, the lens should not be clamped or restricted in any way.

However, a collar around the lens on the block may be used, provided it does not touch the lens, and an adequate

aperture on the upper side provides free entry of the ball. The lens cap shown in figure A.3 is a suggested conformation.

To avoid surface damage from the impact of the ball, the lens may be inserted in a polyethylene bag or covered

with polyethylene sheet before testing. The thickness of the polyethylene covering the lens should not exceed

0.076 mm (0.003 in), and should conform to the requirements for polyethylene sheeting, Type II, given in ASTM

D2103. The protective sheet should be in contact with the lens surface in the test area before the ball is dropped.

NOTE - The use of plastic film can not be used when impact resistance of lenses is verified by a statistical sampling plan.

This is another excerpt from the ANSI wich discusses the impact ressistance that dress eyewear needs to meet. As long as the impact resistance is meet their is no specification on center thickness. You can run a few lenses in each material and try out the center thicknesses to see at what point they break and then add to the lens thickness slightly from their to be sure you are in the safe zone. Keep in mind that you will still have to test your lenses to meet the standard. If using the statistical method I would recommend surfacing a sv cr-39 with all your lenses and then drop ball testing on this lens, if the lens is OK then you can consider all your lenses OK if not then you should test them all and make sure CT are comming out OK and that the generators and polishers are all calibrated and working to spec.

Keep in mind that when you order a lens from a lab if you don't specify CT they could surface a little thicker to avoid high percentages of breakage or they may even allow some thickness as a buffer to reblock and surface if the Rx coems out off.