# Optical Forums > Ophthalmic Optics >  Strange surfacing Problem

## edKENdance

Thought I would bring a little life back to the OO forum.  We're on our 3rd pair of lenses for this baby.  It's not an unusual request.  A pair of progressive transitions in a semi-rimless frame.  The rx is a plus 4.  I myself probably wouldn't have sold it in this style of frame for cosmetic reasons but that's not the point.
The first pair we surfaced as normal.  They came out about 6 tenths thin.  What are you going to do?  We edged them and of course they were too thin to groove.  Everything was checked and everything was correct; pressures, fining times, etc...
Pair 2 was generated the exact same way because we thought that the problem was an anomoly.  Apparently not; they were also thin.
Pair 3 we generated them 7 tenths thicker then they were supposed to be.  They came out more than a full mm thicker then our job ticket stated they should be.  We eyeballed it and decided that we should just cut them.  Guess what?  One lens was still to thin to hold a good groove.
I can't get my head around this one.  It hasn't happened with any other similar jobs.  All of our calibration is correct.
Of course this happened to be a special order lens tacked onto the fact that we're mailing out the glasses.
The frame measurements on the job were correct, everything was right.  Weird glitch? Similar stories more than welcome.

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## Jeff Trail

Ed,


    You can usually track this back to the software..I know if you are running inovations you might run into this problem in PAL's on the plus side and taking the location of the oc's, if you let the program figure it out for you depending on the power/frame and fitting and PD...
     I know also that it maybe a lens problems vs. pad removal as well, you said "transitions" do you mean transitions or some other material (ie. sunsensor and on and on)
     Myself I tend, when using inovations to change the parameters at times depending on the frame and material and fitting...
     For whatever reason sometimes the software tends to go a little crazy when all the planets line up a certian way (lens design, material, frame, power etc., etc.)
     Playing Sherlock Holmes here it isn't the genrators or your removal would be off on everything, not the cylinder machines or any other step in the process.. I would tend to track it back to the software myself.
     BTW did you caliper it when it came off the genrator to verify the CT? and than again after the first fine? (I'm sure you did) just to make sure the correct pads were being used :)

Jeff "back to the ranks of the unemployed" Trail

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## edKENdance

Jeff "back to the ranks of the unemployed" Trail

Now I'm scared.

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## JRS

Whereas, I am not too quick on blaming all this on the software... I have to ask, since you mentioned it was a special order. "Was the lens detail (TBC, Ref Cross location, etc.) and data points already in the software package, or did you run this as some form of 'generic' progressive?"

You also did not state what lens design this "transition" lens was. Can I inquire?

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## edKENdance

JRS, it was only a special order due to the add power.  I plugged the OPC's in and the software recognised it.  Everything was measured.  BTW it was an essilor transition 500/150.

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## shanbaum

> *Jeff Trail said:* 
> I know if you are running inovations you might run into this problem in PAL's on the plus side and taking the location of the oc's, if you let the program figure it out for you depending on the power/frame and fitting and PD...


Jeff, I didn't know that you actually had any hands-on experience with Innovations.  Are you suggesting that Innovations doesn't calculate plus power progressives correctly?  I'd really like to hear more about that, if that's what you mean; the implications for the 50,000 or so pair that we're going to be running today could be significant.

I can't quite make out the bit about "taking the location of the OC's".

The information supplied boils down to this: two pair of lenses were run in exactly the same way and both came out 0.6mm thin.  A third pair was run in the same way, except the thickness at the generator was increased by 0.7mm, producing a lens some 1.0mm thicker.

That alone suggests that something is amiss; in any case, a properly-functioning generator should produce consistent _changes_ in thickness, even if the thickness itself is incorrect.  The latter can result from lots of things, but the most common causes are related to block ring diameter, and the sag of the lens in the block ring (which is expressed as the "front curve" for most generators).  In the case of a progressive, the tilt of the lens in the block ring can also cause a thickness error.  Did the amount of prism in the finished lens vary from one iteration to the next (especially the third)?  And of course, with an improperly configured, or improperly calibrated machine, anything can happen.

You mention that the lenses were special-order because of the add power.  It would be helpful to know all of the Rx parameters; also, was a tracing of the frame used in calculating the job, or just manual measurements?  What software, and what equipment are you using?

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## Jeff Trail

Robert,

   Yes I have run Innovations, and yes with the latest updates and on and on :) I figured you would get "touchy" about the suggestion it was the software, but it does NOT happen on every plus RX and so forth but every once in awhile  (as I said) when a few things line up in the system it just comes out whacky.. all I can say it has happened with me a few times and I did what Ed did and changed the parameters .. for whatever reason it comes out this way I don't know, the other 99.999999% of the time I have and had no problems with your software so be nice..
     If I knew you was going to have a cow ;) over this I would have kept copies of the tickets where it went wrong, it just stood out in my mind because it was also the same lines of RX combination as Ed's .. so you figure with all the stuff I have produced using your stuff (software) .. and I remembered these few times it went this way.. you still are not rating all that bad, so cheer up.. I'm just posting what I experienced, how you think I am wrong. oh well that's what makes the internet fun, I just tossed out something that has happend to me..  Oh and if you want something to think about.. yes it was a PAL and yes it was transitions where my pairs went a little whacky.. now it might not be the software as in you are getting so defensive about as in the software did not account for certian things outside of the normal conditions, gee which would be silly to account for if it happens only  rarely.. wouldn't you agree with that? 

    It's almost the weekend so lighten up, it's 85 out and sunny, maybe the cold weather up your way has you down.. come to Florida and relax a little .. we could drink a few fruity drinks and make fun of the republicans on the nice sandy beach of key west..

Jeff "to tired to quote" Trail

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## JRS

Well put Robert - that is where I was headed once he answered my additional questions. Everything is inter-related on the CNC's, but to just automatically blame the software struck a nerver here too. Jeff, I have no connections to Innovations, but like Robert, I thought you were a bit too quick to jump to that conclusion.

edKENdance - perhaps you can provide Robert (and the rest of us) with some details from the various work tickets - and what displays on the generator screen.

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## shanbaum

Sorry if I appear touchy, Jeff, but the fact is, it's real easy to say that eveything's calibrated, and all the machines are working right, but something's come out wrong, so it must be the software.

When our customers contact us with problems like these, we try to figure out what's going on.  Doing that requires a lot more information than was provided here.  I can tell you that in the majority of cases, these kinds of problems turn out to have nothing to do with software at all; when one is related to software, it's almost invariably related to some configuration parameter, or some aspect of the lens description, being set incorrectly.  Because this Rx was described as having an unusual add, it makes me suspicious that the sag table used for the selected lens _might_ have an error in it; since the sag table contains discrete data for different base curves, adds, and layout dimensions, it's possible for an error to lurk in a little-used combination for a (surprisingly) long time before anyone brings it to our attention.  Sometimes these errors are in the data we get from manufacturers, and occasionally we've screwed up their data importing it into our database.

But _way_ more often than not, it's something else entirely.

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## edKENdance

THE OO IS ALIVE!  ALIVE!
-dr. Frankenstein

I don't hve ready access to a scanner but I'l bring home the ticket and the SGX parameters and plug them in later tonite.

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## Jeff Trail

Robert, JR,


    You guys are going to the opposite end of the spectrum, when I said software it could be any number of things as even Robert pointed out.. not the basic language but maybe some paramter in the program.. I tend to try to link things to where the most probable could happen, since it was not a wide range of problems on a repetitive basis but it did repeat on this one combination of design, material and parameters I would take a look at the software.. you guys think I'm saying it is "bad" software.. I just said look at the software AND the info that was being put into the system...
     Now I had the same problems in the software (where exactly I do not know in the list Robert placed) but it is amazing that it was with an Essilor product in Transitions and a PAL with a plus power and the problem was in thickness (removal)
      I tend to look at the whole picture first.. if it was something else I would have tended to hook it upto the pads being used may be to aggressive for transitions in this case or pin pressure/run time.. but since it was only one pair that stood out and was asked about I take it the other things were in calibration..
      I know when my problem popped up I started at the cylinder machines and worked my way back checking everything out.. I always try to nip problems in the bud as fast as possible especially in wholesale where our profit margins are so slim...
      I guess I could see it from you two guys point, I said software and it was a knee jerk reaction (or that hitting the nerve) that it was in the whole language of the software as a whole...I thought I was telling him it was a certian glitch when a bunch of stuff comes together.. oh well that is why I'm a lab rat and not a programmer ;) 
      I might say "software" but it could be any part of that software, as in the version of Innovations I was using the ET and CT changed from design to design in PAL's just because someone put that info in it, the person who loaded up the parameters was the culprit, but I still, if talking to someone would have said it was software that is where we traced the thickness problem back to.. it's just habit.. I could have said it the long way, but most times they just wanted the quick answer and more importantly "did you fix it" answer :)

Gee, spring is just around the road.. hope everyone gets in a spring time mood :)

Jeff "to poor to afford a quote" Trail

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## edKENdance

Job Ticket for right lens:

Lbase 1.50
lcross 1.75
block blue
inset 2.5
up 4.0
cyl axis 170
prism axis 325.41
prism ring 1.14
gen base 1.50
gen cross 1.75
set gen thk@front 5.7@5.43

SGX job screen

cr-39
foam
blank front curve 5.43
blank back curve -6.39
blank diameter 77.00
blank edge thckness 11.90
base curve -1.50
cross curve -1.75
cyl axis 170.00
CT 5.69
a decentration 2.50
b decentration 0
prism power .64
prism angle 270.
block curve blue
block diameter 54.58
ring height 11.8
ring diameter 60.00
safety off
crib off

Sorry I didn't bring the frame specs home but I think I had to go 5 in on each eye.

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## Jeff Trail

Ed,

   You used foam tools on both lens? was it the same power OU? did you cut two tools? or use one for both as well as the same pad? :) ... also was the power right on in both lens when you checked them in the lenometer?.. gee you are not going to make it a foam bomb tool problem after I spent the time trying to prove my point on the software.. ya stinker you.. :Rolleyes:  

Jeff "I hate what foam does to mid index powers as well" Trail

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## JRS

I'll let Robert post for/with answers first, since he is certainly more familiar with his software than I, but I will ask a few additional questions, if you don't mind...just for my own benefit

I noticed you had foam lap cutting active, so do you normally cut "foam" laps on your jobs, or is this a rare case? 

Do you block on GC (geometric center) since the tickets shows inset = 2.5, up = 4.0? and if so, why does the SgX show A = 2.5?

The ticket says "set gen thk@front 5.7@5.43" (which I assume is TBC @ GCT), but the SgX has a TBC = 5.43 and CT = 5.69. Doesn't the ticket want you to enter "set gen thk@front 5.7@5.43" before running? It's possible that they equal out in sag depth, but it's too late in the day to calc that out right now.

Is this a Natural Progressive 1.498, Transitions Xactive? The parameters seem to indicate that, although the TBC is flat by 0.02 diopters in your system.

I'll wait for Robert's post.


Oh, and Jeff - when you said software I assumed you meant the software (programs) as opposed to database errors. To me they are not the same. Kinda like putting water in your gas tank and saying it's the cars fault for not working right.

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## edKENdance

Jeff,  the powers were different but similar which is why I only posted one eye.  The powers were bang on.


JRS, never had a prob with foam laps.  In rare circumstances we have been off power by .25 dioptres which is easy to fix.
We inset on the CS7 2.5 to the right with the fitting cross 4 up




> The ticket says "set gen thk@front 5.7@5.43" (which I assume is TBC @ GCT), but the SgX has a TBC = 5.43 and CT = 5.69. Doesn't the ticket want you to enter "set gen thk@front 5.7@5.43" before running? It's possible that they equal out in sag depth, but it's too late in the day to calc that out right now.


We don't really use that device anymore.  When we were using our old generator it was essential but the SGX takes the fining time into consideration when establishing  thickness.

It is a natural transitions.  I'm not sure what you mean by Xactive.  The box is black and blue.  Didn't bring any of that home with me.

I really appreciate the info guys.

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## Jeff Trail

some other things does not look right here.. if in Innovations and the edge thickness in my version of innovations is different from the one on your ticket.. something looks kind of weird on the amount of prism used as well :)


   JR,

     Well you and Robert are in the program fix'em up stuff side and to me when I say "software" it meant anything and everything from the person keying in the job may have made a mistake to a parameter thing.. like I said.."software" :) BTW that sag is for a 1.501 transition a 5.50 base lense that part is right



Jeff "amazed by the versions of one program can spin off" Trail

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## shanbaum

JR, the layout instructions and decentration at the generator are consistent; if the LRP is 2.5 in and 4.0 up from block center, decentering 2.5mm puts the back-surface PRP on the dot, where it belongs.

The fact that the SGX receives decentration also explains the difference in the prism values - those on the workticket include the prism for decentration, those sent to the generator do not, since decentration is specified discretely.

The difference between the "set" thickness and curve on the workticket and that sent to the generator is also normal; the workticket values are frequently mangled in various ways - to compensate for the difference between the block ring diameter used, and the one implicit in the generator (à la 113), or to keep the setting at the front of the machine (also à la 113).  The SGX gets a front curve value that is convertible directly to the sag of the lens in the ring (which is usually deduced from sag tables provided by the vendor) along with the actual thickness to be produced; the SGX also receives the ring diameter and height, so it doesn't need any mangling.

Of course, I can't say anything about the thickness that was calculated, as I have no information about the layout geometry - frame dimensions, PD's, LRP height.   

It would indeed be real nice to know exactly what lens we're processing here, too (the OPC code would be fine).

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## JRS

Robert, it appears to be a Essilor Natural Transition -in either 1.501 or 1.498 (depending on how you set these).

Thanks for the info on the ticket - haven't spent enough time looking over a Innovations ticket to understand what prints.

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## Jubilee

The lens he was using is the ormex transition III in the Essilor Natural.

He isn't the only one who has had numerous issues with thickness particularly on the plus/rimless combos.

I actually kept track of all of the times it occurred over a several month period. Then sent them to our quality manufacturing dept.

The data as I can recall that seemed to coincide was...

Ormex Natural
Plus
Rimless
flat curves (3 range and down..)

The larger the A.. the worse it got.

All had spot on powers, any prism thinning was as calculated, and ct was as or in some cases thicker than as specified by job ticket.  Frame measurements were off in some cases, but on an edited job ticket, it didn't make any difference to whether the lens passed ET or not.

I haven't processed any combos like this in a while since I convinced my retail staff that this was not a good combo. Especially since they loved to put them in the metal lined semi-rimless so they chipped like crazy within a few weeks! 

Of course our Quality Manufacturing dept never really got back to me on it...though the last few plus rimless ormex we processed turned out ok. They didn't have the super flat curves though..

Sometimes I think though that our SGX is possessed and it has to believe that we care.. If you give it a bit of TLC.. change the blade (even if it doesn't have the full # of cuts you normally get out of it) clean it out and take some wd-40 to the slides and ballscrews (since it is a cleaner and not an oil :P) Check calibration.. Stroke the lid lovingly while telling it that its a great generator...

Well you get the idea.. That seems to solve 95% of any power/axis/prism/thickness issues we have...

Cassie

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## shanbaum

I won't be able to get to it for a few days, but I will talk to the support folks about it. 

When gathering data to troubleshoot any manufacturing problem,  please be thorough.  We really have to have precise numbers - not, for instance, whether it "passed ET", but what the thinnest edge _was_, and _where_; not that the prism was "as calculated" but exactly what you measured; same thing for the frame dimensions. And as I told you before, any changes in the layout geometry between surfacing and finishing can really screw things up.  So, measure everything, and report everything - even the stuff that looks right.  Even the obvious stuff.

I'll give you an example of why this is important.  A fellow calls up the other day with a thickness problem.  His minus lenses are OK, but all his plus lenses are around 0.5mm thick.  Turns out (an hour later or so) that his minus lenses were "ok" in that they were coming out around 2.2mm.  The nature of the problem became much clearer when we found that the CT we were specifying was 1.8mm.  Turns out, _everything_ was 0.5mm thick; their stock removal was mis-specified.

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## Jubilee

I understand the more info the better...

Unfortunately I no longer have any  of the tickets as they were sent off several months ago..So I don't have all the information. (my memory isn't that good ;) )

I am not sure if they even still have it or even bothered to review it since it has been so long. I know they have updated the system a couple of times since I last talked with them.

I might look for some of my older posts on here and I know I gave actual numbers. At the time I was trouble shooting, I actually was keeping copies of job tickets, writing actual ct/final et.. any changes in frame measurements etc.

As I said, I sent it all off, and then a few weeks later we had an update to the system and I haven't had any issues since. So I thought it had been resolved..

OH well...

I would like to think that people could be a bit more critical in their thinking before calling on the experts. I hape all of my associates and would be able to at least look at thickness on all lenses.. yeah if it is .5 mm thicker than called for in minus form, that makes an ever bigger difference in plus.. If frame measurements are off, that greatly affects plus thickness calculation .. I would think these are common sense type things. 

I was just hoping to add a bit more info than what Ken had to offer.  I recognized the situation as being very much like one of my own.  So Ken don't get frustrated yet ;)

Cassandra

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## edKENdance

Here's the Right OPC 0203809025
A 50
b 33
FPD 69.5
Patient PD 31

The lenses got tossed but guess what, we're surfacing another similar rx on Monday.  This time it's a 500/125 with a much bigger A meas.  Wish me luck.

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## shanbaum

I _will_ look into it.  Unfortuantely, it will have to wait a few days for me to do so personally.

I will send a message to your support center (today) and ask them to review these posts and contact one of our guys on Monday.

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## Jerry Thornhill

I had a similar problem recently and it was driving me nuts. I finally found the problem and it was in the blocking.

I still use alloy and an old Coburn Blocker. The wrong base block can cause the problem along with the amount of pressure applied and where it is applied. That can also cause the amount of prism thinning not to be exactly what was specified.

Jerry

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## Rex

The OPC listed above (0203809025) is for a Plastic - Transitions 1.501 - Progressive - Natural - Next Gray - 550/175 77MM

So the "FlexTint" anomaly doesn't apply here. 

My guess, especially given the "A" & "B" given is that "manual" frame measurements are being used.  If you have access to either a tracer or protractor and vernier calipers to take precise measurments as well as an *exact* ED Axis. Provide this information to Innovations and you should see better thickness calculations.

The default ED Axis value used w/ Manual frame measurements, will normally result in excess lens thickness, so there may be more factors at play here.

<give that a try and posted the new and old Finish CT>

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## edKENdance

Thought I would just mention that the "similar" job we surfaced on Monday was fine however someone had ordered a Sola VIP transition lens so it can't really be compared.

Hey Jubilee, we also surfaced an instock flextint semi-rimless which was quite on the thin side.  A few extra seconds during the fining process would have nixed it.  Still wouldn't be surprised if it comes back with a chip.

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## Pete Hanlin

I tried to read most of the posts to see if this has been covered previously, but I haven't seen it, so...

Was the frame actually traced- or were the only datum measurements given?

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## edKENdance

Hey Pete, the frame wasn't traced but the measured were accurate.  BTW we've started adding .3 to our centre thickness which seems to be ok for now.

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## Pete Hanlin

Actually, even with good measurements, you can get thickness errors that are avoidable with a tracing.  I have a nifty graphic that shows why (actually, I think its from JRS's files).

Glad you've found a solution, however!

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## Jubilee

I would love to see the graphic. Unfortunately the way our systemes are set up, tracing normally doesn't occur till it is on the finishing end of things. The tracer is on its own system with the edgers only.

If it would be more beneficial to have them traced before hand, since accurate measurements alone aren't sufficient, I think this is something we should get out to as many of our stores as possible. Is it being suggested that all the equipment should be on the same system. So that the tracing information gets fed accurately to innovations? How much better is this than just getting accurate measurements? I am looking from the perspective of, if my store has issues with thickness on a couple to three jobs a week, and so does my husband's, and so does Ken, then logic says that we are wasting lots of lenses, and money every week that might be preventable. If I can get a good arguement for this, I can get it presented to the people that can change it...at the end of next week.

Thanks, 
Cassandra

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## Blake

We've started tracing ALL plus lenses over +2.00 - especially rimless.  The new job ticket (using tracer measurements) sometimes changes CT by as much as 1 mm!  
Too bad there isn't an easy way to get that info. to Innovations the first time.  Unfortunately, Eyenet doesn't have a place for ED Axis.


Blake

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## zonelinks2004

Hi all!
i am a new memeber.
Can somebody please let me know wat transition lens are?
---------------------------------------
http: www.zonelinks.com
--------------------------------------
The Power Link Dimension

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## zonelinks2004

hello every body!
wat is the bone of contention here?


---------------------------------------------
http://www.zonelinks.com
---------------------------------------
The Power Link Dimension

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## edKENdance

Here's a new one for anyone using an SGX.

OD +8.50 -50 x75
OS +7.75 sph

We surfaced with a spectralite 7.75 base and 1.75 add ST28

OS was perfect

OD was messed up, big time.  First of all, we have our SGX set to generate multifocals with the reading side in the down position.  The specs in the SGX were correct but instead of rotating the axis to the correct "down" position it was 90 degrees off.  We don't regularly do these kind of powers instore so we trusted the specs and figured that because it was a small cyl we could always change it if it was off axis.  We added 3/10's thickness to the specs because we knew there could be problems.
After surfacing we ended up with a +13.00 about 3mm above the seg with a 5 dipoter swing about 5mm above that to a +8.00.  I am familiar with the swing of powers in aspheric lenses but this seemed waay beyond normal.  Do you think it was a computer glitch caused by software?  I Work for LC but if I was an independant that spent a ton of cash on this machine should I be ticked off?  We ended up farming the job out to our lab that will most likely mess it up.  Can't blame 'em for it now.  It's still bugging me.

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## Jubilee

I seem to recall having that problem once before..What lap did it call for? Did  you have to use foam? Does your generator cut foam reliably? ( I know our loaner right now doesn't, we have to comp it) 

I am off today, and tomorrow is a trip report, after they are gone and if we aren't busy I may try to run a rxcalc and see what I come up with.

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## shanbaum

> Here's a new one for anyone using an SGX.


What you really need to do is contact your Innovations Help Desk.

The first thing they're going to ask you for is a copy of the job ticket, and a transcription of the information that was received by the generator. 

The 90-off bit can happen if Innovations is set (as it is by default) to rotate the surface by 90 degrees to keep the flatter curve the base; the generator may do the same thing (depending on the software version in the SGX).

This happens most frequently when grinding a saddleback or convex surface, in which case you could end up with (for instance) a +0.50 base (convex) and a plano cross - you'd be better of with a plano base and +0.50 cross, so that's what we do.

Regarding the power, well, I'd need to see some of the info I mentioned.

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## edKENdance

Here are the generator specs in brief:

blank front curve:7.59
blank back curve:-6.00
diam:80.00 mm
edge thickness:8.9
Base curve: -0.16
Cross curve: +0.33
axis: 75 degrees
centre thickness:9.12

no decentration and no prism power.

Forced aspheric on.

I notice on the job ticket that the base is set to .12 and the cross is set to minus 0.37.  Not sure if I copied the info from the SGX correctly because the +/- is reversed.  We often see 1/100 increment differences between our job ticket and the specs on the SGX but I didn't notice this untill now.

Let me know if you need more info and thanks for the help.

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## bwheeler

Does the program account for the asphericity and total add of the lens to calculate final thickness perameters? When the lens is too thin, where on the shape is it too thin? Could be a combination of the above mentioned and cylinder power. There is voodoo in the menudo.

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