Cleaning Up Your Consumables Process Part II

By Julie Bos
Last October, we encouraged you to take a hard look at your consumables process and to weed out any glitches that could cause potential errors. We presented several common laboratory mistakes, as well as viable recommendations for how to correct or eliminate them altogether.

In this article, we’re taking the discussion one step further, by presenting the latest products that can help you maximize your progress. Once again, we sought the input of three industry experts: Al Bednar, director of sales and technical services at Practical Systems, Inc. (PSI); Steven Schneider, sales manager of ophthalmic consumables at SatisLoh; and Tim Spangler, V.P. of operations and international sales at DAC Vision. Consider their advice and product recommendations that can help you continue cleaning up your consumables process while increasing your lab quality.

Surfacing

Strategy: Avoid wrinkles by properly affixing surface-saver tape.

With the increasing number of lenses requiring backside spin coatings and/or AR treatments, more and more labs are using surface tape. However, wrinkles in the taping process causes problems, including potential damage to a generator’s cutting tool if a lens de-blocks.

Product Recommendations:

DAC Vision-The ST-1645 3M Surface Saver Applicator can help avoid wrinkling during the taping process—and is still one of the most reliable machines on the market today. Used in conjunction with ST-9942/3M Surface Saver Knife and ST-9944 3M Surface Saver Knife Blades, your lab can be assured of proper tension and clean cutting.

PSI–Manual taping machines, such as PSI 390 Tape Dispenser, are compact, economical and easy to use—making them ideal choices for smaller labs.

In larger-volume labs, PSI recommends the Automatic Surface Tape Applicator (ASTA), which helps lower costs, increase productivity and reduce spoilage. With an output of up to 300 lenses per hour, this applicator can essentially out-produce two operators using conventional tape machines and hot knives. Plus, since it’s automated, it can also reduce repetitive motion injuries, as well as potential harm done by knives and razorblades.

Satisloh–For automated taping, Satisloh recommends Autotaper—an automated system that tapes up to 250 lenses per hour, wrinkle-free—and Autotape XL, a special size roll of surface-saver tape that provides up to five continuous hours of production between change outs. For manual taping, try Eurolens 1400 surface-saver tape, which has been tested and proven with all of today’s high-speed generators.

Strategy: Choose the right surface-saver tape.

Because today’s labs have so many surface-saver tapes from which to choose, it’s essential that you select the best tape for your individual equipment and process.

Product Recommendations:

DAC Vision–DAC Vision offers a wide variety of lens protection tapes for alloy blocking. Products such as ST-4004 and DV-4400 blue lens tape are the highest quality offerings. ST-4004 is recommended for manual applicators (along with the ST-1645 device mentioned above), while DV-4400 triple roll tape is designed for automatic applicators.

PSI–You can also consider PSI’s Blue Lens Saver Tape, which allows the alloy to separate from the tape for proper de-blocking while conforming to all lens types without wrinkling.

Satisloh–The company’s Eurolens 1400 (for manual taping) and Autotape XL (for automated processes) have been thoroughly tested and proven to provide consistent performance and reliable adhesion, yet can be removed easily without adhesive residue.

Lens Blocking

Strategy: Eliminate waxy residue on lenses during lens blocking.

For those using a wax blocking medium, the best way to avoid waxy residue on the lens is to use a quality lens protection tape.

Product Recommendations:

DAC Vision–DAC Vision’s ST-4006 tape features excellent block-side anchorage to prevent generator de-blocking, even under high-torque applications. The specially designed lens side adhesive properly bonds to the lens surface, yet releases cleanly after generation, leaving the lens clean and free of waxy residue.

PSI–PSI’s Clear Tape also protects lenses from waxy residue and eliminates messy wax clean-up. This tape provides protection to the front of the lens surface, which lowers reject rates during AR coating.

Fining

Strategy: Select the right fining pad.

In today’s market, labs must deal with many substrates that have different processing requirements. Especially with polycarbonate and Trivex, the right surfacing process is critical to eliminating challenges with backside and anti-reflective coatings.

Product Recommendations:

DAC Vision–DAC Vision’s new Harmony one-step fining pads offer the latest technology for one-step fining on demanding resin materials, including polycarbonate, Trivex, CR-39 and Hi-Index. Their unique abrasive design allows fast, clean cutting, while reducing common heat-related issues. The result is a high-quality surface that enhances the polishing process.

Satisloh–Satisloh’s exclusive P800 one-step fining pads ensure consistent stock removal and superior surface quality. This pad, along with Satisloh’s Ultimate White polishing pad and Poly-Pro polish, constitutes a complete system to handle every mix of lens materials, providing consistency and quality.

PSI–Higher consistency is why PSI recommends using a complete surfacing system that uses 3M microfinishing pads, high-quality Shawsheen polishing pads and complementary high-grade polishes. Using the latest pad and polish technologies, PSI now offers Trident Systems, which are production-proven to provide the best possible lens finish for today’s materials.

For one-step processing of CR-39 and mid- and high-index lenses, PSI recommends MFS11-7CSF 11-micron violet-striped film fining pads or MFS15-7CSF 15-micron film orange-striped fining pads. For polycarbonate and Trivex lenses, try MFS30-7CSF 30-micron, green-striped film pads or the 35-micron yellow-striped film-fining pads. For two-step processing, consider MFS50-7 50-micron purple-striped film first fine pads with MFS15-7 15-micron orange-striped second fine pads.

Polishing

Strategy: Choose the right polishing pads and polish.

As with other surfacing processes, you should choose your polish based on your most frequently used lens material. Labs that produce a high mix of AR-coated lenses usually prefer premium offerings in an effort to reduce spoilage from their coating equipment, as AR-coated lenses typically magnify surface defects.

DAC Vision–DAC Vision’s new HD-360 premium lens polish and P4 polish pad system is a superior combination that’s perfect for demanding applications. HD-360 offers the latest in slurry technology and chemistry, with the highest clarity of any polish on the market today. HD-360 is a high Baumé polish, yet has lower viscosity, making it very user friendly. Its excellent suspension characteristics extend slurry life, while assuring consistency and ease of mixing. The HD-360 chemistry is non-corrosive and equipment friendly. The special formulation reduces pad carry-out and allows premium polish pads (such as DAC Vision’s P4) to perform to their optimum capacity.

PSI–PSI’s most popular polish pad is the new Pink Perfection, which offers varied fiber lengths and densities to hold the polish on the pad for superior surface quality. It’s twice as durable as other polish pads because of its high density and 25 percent thicker carrier. Plus, it’s long-lasting without causing excessive fiber build-up in slurry. In addition, Pristine polish is a high Baumé polish that works well on all lens materials. Although it was developed for polycarbonate and Trivex lenses, it imparts a high surface quality with less haze and superior clarity on all material types.

Finishing

Strategy: Choose the right blocking (finishing) pads.

Selecting the right finishing pad has changed in recent years, thanks to the introduction of new and improved slick coatings on lenses. Labs no longer stock just one pad that works on all lenses. Indeed, most labs now have one blocking pad for their uncoated and hard-coated lenses, and another designed to work with today’s advanced coatings.

Product Recommendations:

DAC Vision–DAC Vision offers a wide variety of award-winning, high-quality finishing pads. Its most popular for standard lenses is BluEdge and SecurEdge. BluEdge offers a unique construction that utilizes thin—yet strong—foam. The benefits are an improved bond between the block and lens, resulting in the consistency needed for reducing axis failures. SecurEdge offers reinforced foam that demonstrates strength and durability. This added strength reduces torque forces in the X-Y direction, thereby reducing axis failures. Both products are OLA Award of Excellence winners; double-tabbed; and come in a wide array of shapes to match today’s varied block styles.

DAC Vision’s HydroEdge, also an OLA Award of Excellence winner, is an excellent choice for super-hydrophobic lenses. The unique foam carrier offers superb torque-resisting properties, while the specially designed adhesive is viewed by many as the most aggressive and best suited for slippery super-hydrophobic lenses. HydroEdge was specifically designed to remain adhered throughout the extended cycle times in today’s finishing rooms.

PSI–For hydrophobic and super-hydrophobic coatings, PSI offers the New SecurEdge Plus—the newest blocking pad on the market. Introduced at Vision Expo East 2008, this pad enables labs to do away with lens tape and dots, and apply the blocking pad directly to the lens. SecurEdge Plus’s dual-adhesive system offers an aggressive adhesive on one side to adhere to the slick surface of the lens without torquing, and another adhesive on the other side that holds it securely to the block. The soft foam surface of the pad conforms to any curve and will resist twisting on the X-, Y- and Z-axes. For hard-coated or uncoated lenses, PSI recommends using the OLA Award of Excellence winner, SecurEdge. This pad offers a unique, reinforced foam that resists torque and a modified acrylic adhesive system that adheres to wide range of hard coatings.

Strategy: Address the challenge of using super-hydrophobic coating.

The introduction of super-hydrophobic lens treatments has been one of the best added features to lenses in recent years. Unfortunately, the introduction of these coatings has simultaneously been one of the biggest processing challenges facing labs today. While a super-hydrophobic layer enhances cleaning ease for the consumer, it can also lead to slippage, and with that, breakage in edging.

Product Recommendations:

DAC Vision–HydroEdge has benefited customers tremendously in meeting this challenge and won an OLA Award of Excellence in 2007. It offers a unique foam construction combined with a super strong adhesive system. Not only does the adhesive bond to the slipperiest of coatings, it maintains its grip throughout the edging process.

Satisloh–Satisloh and 3M co-developed the LSE (Low Surface Energy) edging pad to process super-hydro lenses. Unlike other pads, the LSE pad features two adhesives. One is for the side that attaches to the block, attaching securely for processing but able to be easily removed without leaving any residue. The second adhesive attaches to the lens, and is specifically designed to work with super-hydrophobic coating chemistry. It provides a secure bond and reduces problems with slippage.

PSI–PSI’s new SecurEdge Plus blocking pads are designed to work exclusively with these types of coatings. (See description above.) Labs can also utilize lens tapes such as PSI LenSaver Dots when working with expensive coated lenses. These can be used under blocking pads (such as SecurEdge) to provide better adhesion to the coating and to prevent scratching during deblocking. They can also be used on the backside of the lens to prevent damage to the lens by the edger chuck during the finishing process. Marking a super-hydrophobic lens also can prove to be a challenge. PSI offers True Mark Hydro Ink, which is designed to stick to slick coatings without smudging or wiping off.

Strategy: Chose and properly maintain your cutting mechanism.

Using the manufacturer’s recommended cutting mechanism for finishing equipment is always a wise decision. Equally important is a routine maintenance program to assure the cutters are changed at regular intervals. There’s no doubt that dull cutters cause finish-room spoilage; and trying to extend the life of your cutter is a strategy that usually backfires.

Product Recommendations:

PSI–Though offered for many years, PSI’s Retrue Service for Edger and Generator wheels is still a viable option for maintaining your cutting mechanism. Within about 72 hours, PSI will remove the unworn section of the cutting wheel to establish a flat cutting surface. To further extend the length of your wheels, PSI also recommends these tips:

• Hone your edger or generator wheel on a consistent basis to maintain a level wheel surface.

• Monitor your wheels often to prevent grooves from developing and becoming too deep.

• Retrue your wheels when the cutting process has slowed down to reestablish a flat cutting surface.

• Stock a backup wheel for use when your wheels are being retrued.

General Lab Processes

Since time is money, it often pays to use the highest quality consumables possible. These, along with solid, repeatable processes afford your lab the best chance to lower spoilage rates, which go straight to the bottom line.

Strategy: Improving lap tool picking and replacement.

One time-consuming step in conventional lens processing is lap tool picking, replacement and storage. By increasing throughput in this area, your lab can save time, hassles and headaches. Product Recommendations:

DAC Vision–The QR-II-C base pad system is a color-coded base-pad system that can help labs increase efficiency by reducing the time it takes to pick and return lap tools to tool racks. It also eliminates the need to peel pads from bare lap tools, enabling staff members to focus on more productive duties.

Satisloh–The Lo-Lift base-pad system also offers help. The base pads attach to lap tools with a semi-permanent adhesive and last up to 500 cycles. They also offer quick release of fining and polish pads, which saves time and prevents possible injury to users. Lo-lift base pads are color-coded for easy identification, thus reducing the time necessary to locate and replace these tools to the storage area. Available in 10 colors and three sizes, Lo-lift base pads can be used on aluminum and plastic laps.

Strategy: Consolidate and maintain lab fluids.

Another way to save time and money is to use recycling and filtration systems for water and coolant, as well as slurry systems for polish. These units not only allow you to consolidate fluids for easy temperature control and maintenance, but also to save large amounts of water, coolant and polish by filtering and reusing what’s already in your system.

Product Recommendations:

PSI–PSI’s 993-2T Recycling and Filtration System is a two-tank system that connects to the drain line of generators, finers or edgers. The fining water or coolant is drained into settling tanks, then pumped through a filter that draws out contaminants before being pumped back into the machine and reused. These systems can save thousands of gallons of water or coolant daily and enables labs to comply with most EPA guidelines. When used with a chiller, the 993-2T helps you control your fining water and coolant temperatures, leading to better surface quality and cost savings by extending the life of coolant and cutter blades/wheels.

Likewise, PSI Central Slurry Systems are ideal for glass or plastic polish. They consolidate the slurry for multiple cylinder machines into one tank, making slurry management easier to control. Slurry is pumped out of the machine to the polishing heads and returned back to the machine through a filter. The cone shape of the tank, along with the pull of the pump, keeps the polish Baumé levels up. When used with a chiller, proper temperature control can be maintained, which increases the life of the polish and improves surface quality.


CURRENT ISSUE


Lab Talk-February/March 2018