By Susan P. Tarrant

So many lens types, so many frame types, so many challenges. That's what in-house labs face every day. Materials, lens designs, special requests, and dramatic base curves all present various challenges during processing. Here, we re-visit some of the more popular topics and problems, and have our edging equipment pros offer advice.

Dolabany Eyewear style Denver for Best Image Optical.

SMALL PALS, BIG CHALLENGES

PROBLEM: We have a hard time fitting all of the parts of the progressive into those small frames.

SOLUTION: Several manufacturers offer progressives with very short channels. If this still does not solve the problem, here's another idea. Add a diopter to the add power. In the small children's frames, the near portion will often be cut off during edging, but adding a diopter to the add power will allow the wearer to utilize the intermediate portion as the near portion. It's certainly not the best way to work, as it narrows the channel, but it's a way around the problem.

Most edgers will handle decentration automatically, and all a dispenser needs to do is block on the fitting cross. But this poses a problem-the edger won't be able to cut it out because of the decentration necessary. In this case, all a dispenser needs to do is block the lens in the passive mode-that is, the operator during layout does the decentration manually-and block on geometric center.

-Franco Aluigi, national product manager, Santinelli International

REDUCING RE-DOS

PROBLEM: Our office is doing a lot more premium product, yet our re-do rates are through the roof.

SOLUTION: The best way to eliminate the re-do is to make sure your office is investing in and taking advantage of the better processing technology that is available.

If the lab is an integral portion of your business, and you recognize keeping jobs in-house as important to your practice that's one of the reasons why investing in technology is so vital.

On average, an in-house lab will see a savings of about $15 per job. That figure goes up considerably when you bring the premium jobs in-house. But you've got to have the right equipment to handle it. In general, you should look for the newest generation patternless edger with 3-D technology. It should also have an integrated blocker, one that gives your tech the ability to input the prescription information, and it will line everything up automatically.

Because of the popularity of high-index lenses, and with the future moving toward the thin lenses and fragile edges, the equipment should also give you the ability to adjust the chuck pressure and adjust the head pressure. It is important to have the capability to make those adjustments on a job-to-job basis, not just once.

-Matt Vulich, vice president, sales, AIT Technologies

PROCESSING POLY

PROBLEM: We have read a lot about processing polycarbonate, and are trying to decide the best possible way to process sports eyewear with polycarbonate lenses.

SOLUTION: Polycarbonate is a popular lens material for sports eyewear today because of its shatter proof qualities. However, processing poly lenses on old-style edgers can be time-consuming because the material is soft, scratches easily, and leaves behind messy debris while edging.

It's best to use one of the new automatic patternless edgers that makes processing polycarbonate fast and easy to do. Look for one that has a wet/dry cutting cycle and draining system that cleans the edging chamber automatically as the lens is being processed. This keeps both the edger and the lens clean, for a better quality finish.

-Greg Dean, technical training manager, Briot USA

SLIPPED BLOCKING

PROBLEM: Sometimes when we're edging AR-coated lenses, the blocking slips, which knocks the axis off and we have to redo. 

SOLUTION: Slippage during the blocking phase happens because the lenses become hydrophobic when AR coated, meaning there can be a slight amount of moisture on the lens.

Therefore, the adhesive tape used prior to blocking can slip, which causes the blocker to slip and the lens to be knocked off axis.

There is a special adhesive disk that can be put on the lens prior to the blocking phase that will eliminate this problem. This "surface saver tape" is smaller in diameter than the lens, but bigger than the block. It allows the adhesive tape to adhere better to the lens, which prevents the block from slipping. 

An added benefit is that the surface saver tape also helps protect the coated lens from being scratched.

-Bill Galindo, president, ODI/Topcon

	Romeo Gigli 212 for Allison Eyewear, Inc.