Barwell-based
True Lens Services has adopted
TaeguTec's TTA101-grade VCGT 110304 FL turning insert after a trial addressed the hand-polishing bottleneck that had been adding time and labour to production of its aluminium camera lens housings.
True Lens designs, engineers and rehouses professional cinema lenses, converting vintage stills optics into modern cine tools used by filmmakers around the world. Alongside this lens servicing, repair and custom mechanical work is carried out entirely in-house.
The company supplies an international client base, and its engineering team won the Bert Easey Technical Award from the British Society of Cinematographers in 2025, recognition of the precision that sits behind every lens leaving its workshop.
Much of what True Lens machines is aluminium, produced on a pair of Nakamura-Tome AS200 turning centres in batches ranging from as few as 50 pieces up to 500, depending on the job. Because the finished components are anodised, any mark or inconsistency left on the surface by the cutting tool is magnified, and the equipment involved is not cheap.
A familiar faceTaeguTec technical sales engineer Brandon Kane had, in a previous role, helped install the pair of Nakamura-Tome AS200 machines already on the shopfloor at True Lens Services, and it was a conversation about that earlier work that led the company to ask whether he could take a look at a finishing problem on its aluminium parts.
Working with an existing supplier's uncoated turning insert, parts coming off the AS200s were failing visual inspection at a rate that meant roughly half of every batch had to be picked out and hand-polished before anodising.
Every mark or burr had to be caught by eye, by operators experienced enough to spot imperfections invisible to anyone else. Left unresolved, that meant added manpower and added time on every batch, a cost that never showed up as scrap or as a cycle-time problem but sat quietly behind every job.
The initial diagnosis pointed at the machines themselves, and a lack of rigidity in the process. Mr Kane had previously worked as a service engineer supporting Nakamura-Tome turning centres, so he was confident that was not the real cause. Aluminium finishing problems this consistent were more likely down to the insert than the machine.
The insert trialTaeguTec's TTA101 grade, one of the first new products released since Mr Kane joined the company, was proposed as a targeted trial rather than a wholesale tooling change. The VCGT 110304 FL insert would be introduced purely for the cosmetic outside-diameter finishing pass, with the existing tooling retained for roughing and general machining. TaeguTec’s TTA101 is a ta-C coated grade, applied at a thickness of less than 0.5µm to preserve the sharpness of the cutting edge rather than rounding it off, with a hardness rating of HV5000 or higher that gives it strong resistance to abrasive wear. Engineered specifically to resist the built-up edge that is a persistent problem when machining aluminium, the inserts rapidly made an impact.
The trial insert was run on one Nakamura AS200 at a cutting speed of 525m/min, a feed rate of 0.07mm/rev and a depth of cut of 0.4mm on the finishing pass. Feeds and speeds were fine-tuned specifically for surface quality rather than cycle time and slowed slightly from where they might otherwise sit. It was a trade-off True Lens Services was entirely comfortable with. In this case, getting the aesthetics and surface finish correct was the key priority - not cycle time reductions.
The formal trial report, compiled by True Lens Services and reviewed by TaeguTec, recorded a significant improvement in surface finish, based on the customer's own visual assessment. The more significant result was tool life. With the previous insert, edges typically needed replacing after 5 to 10 parts. The TTA101 trial edge was still producing high-quality parts a month after the trial began and had not required changing.
As the insert is still in service well beyond the initial trial period, this substantial improvement has yet to be benchmarked against its predecessor. With no insert failures to date, True Lens and TaeguTec still cannot quantify the tool-life gain. However, with fewer insert changes, less operator intervention, and more consistent production between tool changes, TaeguTec has enabled True Lens Services to meet its surface finish requirements without switching machines, tweaking processes, or resorting to excessive post-machining hand-finishing.
The results were enough to move True Lens Services from trial to purchase. The company placed its first order, a box of 10 TTA101 inserts, and extended the use of the TaeguTec grade from the single trial machine to both AS200s.
Mark Lightbown, workshop supervisor at True Lens Services, said: “The TaeguTec inserts have made a massive difference, and we now run the TTA101 inserts on both machines. Whilst still early days, the savings from eliminating hand finishing are considerable. Equally important is process stability, with no need to tweak the process and full confidence that the surface finish on a batch run will not diminish. This is a huge benefit to our highly skilled machinists.”
Parts finished with the TTA101 insert are now coming off the machine ready for anodising, removing the secondary hand-polishing step. For a business where every part is inspected, and where every imperfection is magnified by anodising, that translates into reduced labour, reduced handling and a more predictable route from machine to finished lens.
The way aheadWith the trial proving a huge success, the next step for TaeguTec's Brandon Kane is to identify further areas where the company’s cutting tools can deliver additional process and productivity improvements.
For detailed technical specifications, expert application guidance, or prompt ordering information, contact your local TaeguTec representative or visit
www.taegutec.com.