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With over 15,000 products, Boston Scientific is a major provider of pacemakers, defibrillators, monitoring equipment, spinal & brain stimulation, stents, catheters and ablation devices.

On one recent cardiac monitoring battery component, Larry Hennig, Â鶹´«Ã½Ó³»­ Engineering Specialist at the company's Arden Hills, MN, facility, reported, "We had an application running year-round on multiple mills, rectangular in shape, consisting of multiple milling operations per part, requiring an operator per mill at all times. Both mill operations consist of multipart fixtures as the process involved running Mill OP-1, light hand deburring and prepping the parts for Mill OP-2 fixture and process, following manual deburring step. The overall process was running around seven minutes per part."

Hennig and his team members determined the Swiss process was more beneficial, because they could eliminate manual deburring and get process time down to around three minutes. One operator could run multiple Swiss machines with the ability for the process to run attended while CNC auto-segregating particular parts for in-process dimensional inspections. The process proved to be more stable while eliminating manual deburring providing a better surface with nearly triple the tool life.

As a result, this new process had a combined six-person headcount reduction. The Swiss manufacturing process is capable of running 12+ hours unattended, holding the targeted .0002" profile tolerance.

Additionally, there was a significant improvement in material savings, according to Hennig: "We were using .300 in. of stock per part for the milling process, while the new process only requires .100 in. of stock material per part."

The machines were provided by the local Minneapolis Citizen distributor, Productivity Inc., partnering with Andy Walser and their tooling representative Terri Farrell. The story might end here, except for a key component in the radical improvement of production on the part. Farrell brought Preben Hansen, President of Platinum Tooling Technologies, into the situation, and Hansen introduced a Heimatec speed increaser (1:4 ratio) specially designed for the Citizen machines.

As Hennig explained: "While this component is not a round part, it is small in size and requires small tooling. We were not getting enough RPM to match the tool diameter and necessary SFM, which was causing long process times and reduced tool life. I have worked with many types of electric spindles and many brands of speeders. With the electric spindles, we had some success on light drilling and small-diameter high-speed milling, but the obstacles we faced involved load on the tool that would cause the electric spindle RPM to fluctuate and therefore leave tool marks across the material-or even alarme-out the electric spindle when load was applied."

As a result, Hennig noted the company needed to rebuild all the bearings and seals on their high-speed electric spindles annually, and additionally rebuilding the previous manufactures gear-driven speeder heads multiple times during the year while running high-production volumes of parts.

Hansen brought Hennig a new idea. Several 1:4 speeder heads and tooling attachments were introduced to provide additional live tool positions and RPM.

According to Hansen: "We achieved a superior surface finish when drilling, reaming, profile and face milling, which improved our tool life and provided a major reduction in cycle time by using these speeders, as compared to the 1:3, 1:2 and especially the 1:1 standard tool provided by the OEM or brand X. The Heimatec speeders provided by Preben have been in operation for over two years and have not required a rebuild. They still feel like the day I brought them into the process."

Hansen noted: "We helped Larry convert the component production process by enabling a single operator, a more stable machining operation, improved cycle times with higher RPM and proper feed, plus the big advantage-an optimum surface finish, which is so critical on these parts. The deburring issue is no longer an issue."

Hennig expanded on his experience: "We were able to develop some amazing new macro features with this latest project, such as rotation macro-offsets for alignment from main to sub, developing safety crash macros to help prevent accidents into toolholders due to limited clearance between sub collet and face of part, as we are only chucking on .006 in. of the part during part pickoff/transfer and have limited clearance on the sub side. This prevents crashes into the cutoff or sub-spindle tooling if set-up or offset incorrectly. Together with our team's tribal knowledge, we designed custom tools that spot, drill, ream and chamfer all with a single tool, keeping the chamfers concentric, as well as the custom deburring tools providing burr-free product. These were all conditions that we struggled with on most on the mills with their need for manual deburring and several tools intersecting the same feature."

Hennig continued: "We have learned over the years that tooling specs rarely work in Swiss applications due to the lack of workholding compared to mills or even conventional lathes. For example, when programming a high-volume product, I usually start at 50% of the tooling manufacturer's recommendations and then run 15-25 test cuts at various speeds and feeds to find the optimal conditions."

He further notes that, when milling on Swiss applications, "I have learned through experience that performing climb milling for rough cuts and utilizing a conventional mill spring or finish pass helps tremendously with knocking off any burrs and provides an amazing finish on all surfaces with extended tool life."

Hennig pointed out that, as with any medical or implantable device, Boston Scientific is tasked with much higher standards compared to most manufacturing facilities when holding surface finish, dimensional requirements and creating no burrs.

Hennig noted: "Here at Boston Scientific we hold every single part to the highest standards cosmetically, dimensionally and functionally. Our number one priority is quality and providing the best patient impacting components, regardless of expense. That is one thing I really value about this company."

Farrell from Productivity added: "It was a no-brainer getting Platinum Tooling involved in this project. Preben, his team and the products they offer to the manufacturing world are all top notch. Having the opportunity to work with Boston Scientific and the caliber of machinists and engineers such as Larry has been one of the most rewarding experiences in my career. This team is not afraid to approach a project from a completely different angle and try new things. That is how you stay on the leading edge."

Hennig concluded: "I highly recommend Platinum Tooling products. They offer a great product, and Preben provides fantastic support and communication. They are open to new ideas and challenges to help support customers' needs while maintaining great price points. I would also like to thank Andy and Terri from Productivity and all their team members who helped support this project."

For more information contact:

Preben Hansen, President

Platinum Tooling Technologies, Inc.

16 E Piper Lane, Suite 128

Prospect Heights, IL 60070

847-749-0633

phansen@platinumtooling.com

info@platinumtooling.com

Larry Hennig

Â鶹´«Ã½Ó³»­ Engineering Specialist

Boston Scientific

4100 Hamline Ave. North

Arden Hills, MN 55112

Productivity Inc.

15150 25th Ave. N

Minneapolis, MN 55447

800-328-3272