Gerber Coburn(Essilor) Kappa edger issue

[Mad12345]

Hello all,

I've been browsing Optiboard for months now, and I greatly appreciate all of the insight that I've gleaned from here. Now, I'm hoping that you can help me with my problem.

We have a Gerber Coburn(Essilor) Kappa edger that we use daily, and sometimes when edging poly or high index we end up with a small chip in one or both of the lenses. It kind of looks like someone slipped with the screwdriver and nicked the lens, but it's fresh from the edger.(It's not my fault, I swear!) It doesn't happen every time, and we've tried to repeat it to no avail. I'm wondering if any of you have experienced the same issue, or if you know of someone that I might contact to help me out with this. I hate having to redo jobs when I did nothing wrong!

Thanks for all your help!

[Chris Ryser]

I have seen this when the lens is moved to the groove and might touch the wheel at the edge. Maybe it does not lift the lens enough.

[PartTimer]

I know it might be a silly question, but did you run all of the diagnostics/calibrations? No codes or anything upon running them? Are these on larger frames? Do you run much CR-39? Is this nick on the edge of the lenses or more central?

I know VSI (Vision Systems Inc) in Tarpon Springs has worked on this machine extensively. You might give them a call if you can't figure it out. I'd be interested to find out what it is, as we own one of these, and every trick I can learn about it is useful. If you need manual pages or anything, let me know.

Also, someone should send Chris a cake when he hits 20k posts.

[Mad12345]

PartTimer,

We do mostly CR39, and we never notice it in that material. I suspect that it has something to do with the difference between processing CR39 and poly/high index. The nicks do seem to appear in the same spot each time, which means that they do only appear on larger lenses. We recently did two poly polarized progressives, and it appeared in both of them. It's exceptionally frustrating. We've watched the cycle run multiple times, and we can't see anything happening.

After all, a watched pot never boils!

[obxeyeguy]

When you say small chip, do you mean a posterior flake at safety bevel point? Your high index issue without cr 39 issue is confusing as I assume they are being run an the same cycle, not the dry rough poly cycle. Stop the safety bevel cycle on a poly, see what happens, you may have to adjust it.

[Mad12345]

We figured it out!

The reason why we could not find a problem with the edger is that the problem was actually with the blocker. Our blocker has three pegs and each of them have rubber feet, but one of the rubber feet had worn down. So each time we were blocking a specific power blank, it would press down into the metal foot and make a small chip/indentation. We were so intent on figuring out what was wrong with the edger, that we didn't even think about the blocker.

[PartTimer]

That's great! It's always nice when it's something minor like this. Perhaps a good lesson on process of elimination. I'll look out for this on mine. I always hate cracking the case with my big dumb Neanderthal hands; switching out the L/R assembly on that thing was a bear for me.

Thanks for posting the followup info!

[Plausible]

We figured it out!

The reason why we could not find a problem with the edger is that the problem was actually with the blocker. Our blocker has three pegs and each of them have rubber feet, but one of the rubber feet had worn down. So each time we were blocking a specific power blank, it would press down into the metal foot and make a small chip/indentation. We were so intent on figuring out what was wrong with the edger, that we didn't even think about the blocker.

I kind of hate to ask this but seeing you first posted 7-7 and posted the resolution 7-19 how many breakages occurred before you figured this out?