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Lighter than aluminium, more haptic than metal –High-precision, lightweight shims for tolerance compensation

Drive technology, mechanical engineering, automotive and aerospace applications in particular require high-precision spacer elements as helpers for fast and low-cost assembly. Georg Martin GmbH developed its multi-layer polyester M-Tech L PET shim specially adapted to meet the lightweight demands of these sectors. Instead of using many individual adjustment elements, the user peels off the excess here and inserts the rest with high precision. The M-Tech L PET spacer element with a thickness of 1.38 g·cm−3 weighs only half as much as an M-Tech L Alu alternative. It is also corrosion-free and lower priced than M-Tech shims made of rust-free metals. Its mechanical pressure-bearing capacity is high and its heat resistance is sufficient for temperatures up to 85°C (source: Airbus) – and above for short periods – which is sufficient for many areas of application. Another practical advantage is its outstanding haptic qualities: the thin films that make up the M-Tech L PET can be peeled off fully or partially as they have no sharp edges.  

All of these advantages have had the result that M-Tech L PET shims from Martin are used at Airbus. All of the adhesive systems used by Martin for the manufacture of laminated shims are fundamentally approved for structural as well as interior cabin applications, with the PET precision elements being used for less demanding applications. On top of all of this, the Martin M-Tech L PET is also ideally suited as a spacer and adjustment element for the mounting of sub-assemblies in industrial transmission and automotive construction, as well as mechanical and plant engineering. Transmission manufacturers in particular are discovering its value more and more as a time and cost-saving substitute for metallic shims.

Martin is currently offering its M-Tech L PET in film thicknesses of 0.05 mm and 0.1 mm. The total thicknesses vary up to 3.0 mm in 0.5 mm increments and versions with film thicknesses of only 0.025 mm are currently being developed. The material that forms the basis of Martin’s M-Tech L PET is Mylar A from DuPont, a highly durable film on the basis of polyethylene terephthalate (PET), which can be machined, thus achieving optically appealing surfaces and complying with the closest tolerances.

Georg Martin from the town of Dietzenbach near Frankfurt, Germany, is certified in accordance with the standards EN9100, ISO 9001:2008 and ISO 14001:2004 and has supplier approval from the likes of Airbus, Airbus Helicopters and Rolls Royce. Production is in conformance with RoHS, PFOS and REACH.