A renowned designer and manufacturer of high-fidelity sound systems — such as turntables, streaming systems, amps and speakers — Linn Products employs some 160 people at the company’s Glasgow-based headquarters.

Moreover, the modular nature of Linn’s hardware and software is such that, rather than pursue a business model of planned obsolescence, the company has ensured that all of its systems are upgradeable and that ‘quality permeates every aspect of the business’s activities’.

To ensure the build-quality of Linn’s products, the company’s staff undertake ‘painstaking inspection routines’ throughout all stages of manufacture; and to reduce the reliance on sub-contractors, further increase the autonomous nature of the business’s manufacturing operation and to provide even greater control over the quality of its components, Linn recently made several investments in advanced machine tools.

These investments included a bespoke manufacturing cell from Mills CNC. This automated system, which includes a Doosan DVF 5000 five-axis machining centre and a Fanuc six-axis robot, now runs unattended overnight and over weekends and has provided significant productivity gains.

Due to the enhanced accuracy and high-yield capabilities of Linn’s new manufacturing plant, Chris O’Brien — the company’s director of operations — needed a new coordinate measuring machine (CMM) that could keep pace with the increased production. Following a successful, practical demonstration at the East Kilbride showroom of Andover-based www.mitutoyo.co.uk Mitutoyo (UK) Ltd, an order was placed for a Crysta-Apex S-series CNC CMM.

Sound perfection
Explaining Linn’s quality philosophy and the purchase of the Crysta-Apex S CMM, Mr O’Brien said: “Ever since Linn Products was established in 1973, we have constantly pushed technology forwards in the pursuit of perfect sound. From our very first product, the iconic Sondek LP12 turntable (pictured), we have been at the forefront of audio technology.

“All of our high-fidelity sound systems are assembled by hand in our Glasgow factory, and each one bears the name of the person who made it. Our systems are engineered to extraordinarily tight tolerances; and to help ensure the continuing premium quality of our products and to guarantee their prolonged superior performance, all systems are painstakingly inspected and tested at each stage of manufacture. Prior to despatch, every completed product is thoroughly tested to ensure that it delivers outstanding performance.

“After bringing the machining of many of our previously sub-contracted, high-precision components in-house, we needed to source a highly efficient and very accurate means of inspecting them. We subsequently determined that a Mitutoyo Crysta-Apex S-series was ideal for our demanding needs, having a work envelope of 500 x 400 x 400mm.

“Following the trouble-free installation our new Mitutoyo CMM, our engineering staff were trained in its operation. They found the operating system and software logical and intuitive and were soon able to perform a range of inspection routines.”

Mitutoyo CMMs are available in a wide range of sizes and accuracy classes enabling them to cover practically all precision 3-D measuring applications. A large variety of contact and non-contact probes are offered, enabling a wide range of measurement routines to be performed. Complementing Mitutoyo’s CMM hardware, the company’s ‘powerful, yet easy-to-use analysis software’ allows all measurement results to be interpreted in a ‘timely manner’.

The Crysta-Apex S-series machines are high-accuracy CNC CMMs that guarantee a maximum permissible length measurement error of ‘E0,MPE=(1.7+3L/1000)μm’ for the 500-, 700- and 900-series machines. In addition, the CMMs deliver a maximum drive speed of 519mm/sec and a maximum acceleration of 2,309mm/sec².

Moreover, the Y-axis guide rails, which are attached to one side of the machines’ granite surface plates, help these CMMs to maintain high levels of accuracy over years of use; while the air bearings have been designed to minimise vibration even during high-speed high-acceleration movements.

In addition, a temperature compensation system means Crysta-Apex S CMMs can guarantee the accuracy of measurement under temperature conditions of 16-26°C, thanks to permanently installed temperature sensors located on each scale working together with sensors placed on the workpiece.